DE102018010197A1 - Electronic element and electrically controlled display element - Google Patents

Abstract

Use of an electronic element with processor and memory function for use as a computer and / or computer element with identification and / or authentication function of a user in a digital network, characterized in that the electronic element consists of at least one hardware element and / or software.

Description

Object of the invention, prior art

The increasing digitization of information, such as that of characters and images, inevitably leads to the fact that information is now preferably viewed directly on the screen on mobile smartphones, notebooks, pads, e-books, TV flat screens, etc. It is hardly necessary or necessary a physical printout of the image and / or character information by printing out, for example to produce on paper or foil material. The information is accessible at any time, quickly and space-saving on the screen and visually ascertainable.

There are now a plethora of applications for digital screens / displays such as electronic tickets, e-books, moderation and presentation texts, digital advertising boards (stadium advertising), traffic and display boards, 3D glasses and virtual simulations, computer games, augmented reality, etc.

Due to the ever-increasing spread of computers and screens in all areas of life, information is increasingly virtualized, to a certain extent as a replacement for physical, tangible material information.

The acceptance and consumption of virtual products based purely on digital signs and images is, above all, the “digital natives”, the new virtual normality and a matter of course. It has a social change, i.e. A cultural change in the handling and perception and processing of information has taken place from material, analogue to artificial, virtual information

This development will continue dramatically over the next 30 years. Artificial intelligence based algorithms from quantum computers will lead to groundbreaking advances in all areas of life.

However, it remains questionable what consequences this development will have for the human body and mind and which psychological and psychological effects are associated with it. Since man, a natural organism, is shaped by the many thousands of years of earth's history, it remains to be seen whether this virtual change will succeed without negative, harmful side effects.

The object of this invention is to propose new areas of application for the use of screens / displays and to offer a technical solution for this which leads to useful and helpful innovations 2 in many areas of life. The invention shows how screen displays can be manufactured in a very thin construction and can be operated from another location by the wireless control by means of an external computer. This will make entirely new fields of application possible that do not yet exist according to the current state of the art, e.g. a digital license plate that is controlled and monitored by the road traffic office or, for example, a furniture surface, designed as a screen display with virtual wood decors that are controlled from the smartphone.

The current state-of-the-art in smartphones has a minimum total thickness, i.e. the outer dimension of the case, of 4.6 mm. According to the computer magazine Chip dated March 19, 2017, this is the smartphone product: Carbon Mobile. This means that the structural arrangement of memory and processor and an accumulator / battery and the screen display according to the current state of the art require this height. There are no thinner smartphones or e-pads on the market at the time of this patent application.

It is also state of the art for screens, such as For smartphones, e-pads and flat screens, the screen is controlled via the internally installed computer / computer.

The basic idea of the invention is to use an electrically controlled display element for the optical signaling of variable information such as characters or images with an integrated electronic element with processor and memory function, characterized in that the control via a wireless connection from an external computer / computer takes place and the display element has a thickness, that is, outer housing dimension, of 0.3 to 4.5 mm, the electronic element having a maximum thickness of 1 mm.

The electronic element consists of at least one hardware element and / or software and / or app application.

Furthermore, the electronic element consists of an exchangeable physical chip card and / or a built-in physically non-exchangeable chip card and / or an element having a function identical to the chip card.

The novelty of the invention is to control the electrically controlled display element via a wireless connection from an external computer / computer in order to remotely transmit and display changeable information such as characters or images on a screen at another location. In addition, the invention proposes that the display element be made very thin, with a thickness of 0.3-4.5 mm.

The wireless connection can consist of a radio and / or light (LiFi) and / or ultrasound network.

This thin embodiment is made possible according to the invention in that an electronic element with processor and memory function is used, in a miniaturized design with a maximum thickness of only 1 mm. The electronic element furthermore has an identification and / or authentication function of a user in a digital network.

The wireless connection is preferably made via a radio connection based on a G-frequency radio connection, preferably based on 3G and / or 4 G and / or 5G and / or a mobile radio connection and / or based on a Bluetooth and / or WLAN, and / or WIFI and / or LiFi and / or satellite connection (GPS).

The channel bandwidth of the radio connection is in the range from 100 MHz to 100 GHz, preferably 800 MHz to 30 GHz, in particular 3 GHz to 6 GHz.

The electronic element is e.g. a preconfigured 3G or 4G. or 5 G SIM card, which automatically turns on when switched on via radio connection to control the display element, i.e. screen displays, with the external computer, e.g. connects to a smartphone and is immediately ready for use. Each display element contains, for example, a 3 G sim card with a unique connection code, the so-called association token: Example 8-digit character code: e.g. AC11-GE4S-P3, which only exists for this one display element. Optionally, the display element can also be assigned its own email address. The 3G SIM card works e.g. internationally in over 100 countries and also has a GPS function.

The electronic element preferably has a maximum format of 85.6 mm × 54 mm, in particular a format of 25 mm × 15 mm and / or 15 mm × 12 mm and / or 12.3 mm × 8.8 mm.

Furthermore, the electronic element preferably has a thickness of at most 1 mm, preferably a thickness of at least 0.3-1 mm, in particular 0.76 mm and / or 0.67 mm, and preferably has a storage capacity of at least 128 gigabytes.

The display element and / or hardware element has at least one camera and / or video camera and / or scan function and / or sensor function and / or infrared light function and / or loudspeaker function and / or microphone function and / or sound card.

The sensor function detects physical, chemical and material properties quantitatively or qualitatively, preferably with a measuring function for temperature, amount of heat, moisture, pressure, weight, distance measurement, rain sensor, sound, brightness, acceleration, PH value, ionic strength, electrochemical potential and / or the material Qualities recorded qualitatively.

The electrically controlled display consists of a screen and / or screen and / or display, in particular a smart display, and / or monitor and / or touchscreen surface or a projected surface.

The display technology of the electrically controlled display is preferably based on the technology of light emitting diodes (LED), field emission screen (FED) and / or liquid crystal screen (LCD) and / or thin film transistor screen (TFT-LCD) and / or Cathode ray tube screen (CRT) and / or plasma screen and / or organic light emitting diode (OLED), SOLED or SMOLED film displays, PLED, AMOLED- (active matrix OLED) or Super AMOLED +, and / or surface conduction electron emitter display (SED) and (or QLED and / or Micro LED (microscopic light-emitting diodes and / or HDR (High Dynamic Range) and / or electronic ink and / or e-paper.

Another embodiment is that the display technology of the electrically controlled display is preferably based on technology of micro LED pixels, preferably with a resolution of at least 7680 x4320 pixels. and / or and / or electronic ink is generated,

In order to produce the thinnest possible design, a film display based on a film, in particular on the basis of petrochemical and / or biopolymeric plastics and / or organic substances, is used, the film preferably having a thickness of 20 to 1000 μm, in particular 20 to 100 µm.

In a further embodiment, the film has printed electronics.

The electrically controlled display element is preferably supplied with power in a wireless and / or wired manner on a technical basis by means of a connection to the power supply system and / or an accumulator and / or induction current and / or by radio current, the accumulator having a maximum thickness of 0.3 to 4.5 mm.

With regard to the design and shape of the display element, it is provided that a screen display can have three-dimensional deformations, and in particular can be rolled and / or folded.

The outer shape of the display element is preferably designed on the basis of geometric and / or free shapes, preferably from rectangle, square, circle, ellipse, triangle, polygon, parabola, free-form elements and their possible combinations.

In the following embodiments of the invention, the use of metal coatings and functional foils is proposed for producing the electrically controlled display element, in particular for producing semiconductor electronics and microtechnology elements.

The production types and methods and embodiments proposed here are particularly economical to produce in large quantities.

Electrical conductor tracks can be produced, for example, by metal coating a film or carrier film. For this purpose, the metal coating and / or the carrier film can be provided both over the full area and over part of the area. It can be advantageous to have several levels, i.e. as a composite layer, to be arranged one above the other with metallized foils in order to implement different electronic circuits with which, for example, miniaturized LED or OLED lights or also foil loudspeakers are operated, which can also be integrated into the composite layer, e.g. in the form of functional film / s.

The metal coating can also be used to produce miniaturized electronic circuits, in particular integrated circuits, in the form and on the basis of functional film / s.

Circuits based on organic and metallic materials can also be applied to organic foils using thin-film technology (e.g. using PVD, CVD, OPVD (organic vapor deposition) processes or also using conventional printing techniques (inkjet, screen printing, micro-contact stamp printing with metallic material), or also by spin coating.

It can also be used to manufacture integrated optoelectronic systems, such as actuators (transmitters) and detectors (receivers), or optosensors, optocouplers or optical modulators, e.g. Photo resistor, photodiode (also solar cell) and photo transistor, light sensors.

The semimetal silicon (Si) or germanium (Ge) or silicon-containing compounds, in particular semiconductor silicon or solar silicon, are preferably used for the metallic layer in the aforementioned examples from microelectronics and optoelectronics. Or, preferably in optoelectronics, conductive coatings made of TCOs (transparent conductive oxides), such as indium tin oxide nanoparticles (ITO). These have the advantage of being transparent and can also be made flexible, and can be used as electrodes in optoelectronic applications, such as flat screens, for example. Touch screens, displays, in particular flexible displays, organic light-emitting diodes, electro-luminescent lamps or also in components from solar technology are used.

According to the invention, for example, display films can be produced for programmable surfaces, i.e. the surface decor e.g. of a piece of furniture, floor or wall surface is shown as digital / virtual wood / stone or fantasy decor, with the possibility e.g. Light / lighting - / movement / information - and sound effects can be staged freely.

According to the invention, e.g. an OLED (organic light emitting diode) or in particular PLED (polymer light emitting diode) film display can be used, based on a plastic film with a thickness of preferably 20 to 500 μm, printed on the circuits using thin film transistors. It is also possible to use SOLED or SMOLED film displays, as the OLEDs made from “small molecules” are called. AMOLED (active matrix OLED) or Super AMOLED + technology can also be used.

With the above OLED technologies use, among other things, the principle of luminescence to produce self-illuminating screens that are based in particular on organic electroluminescence. According to the invention, organometallic complexes or substances are introduced into the composite layer (B) using a polymer carrier layer (T) as a partial or full-area layer of metallic material.

Polymer films made of polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate (PC), polyethersulfone (PES) and polyimide (PI) are preferably used as the flexible substrate material for flexible transparent electrodes. The indium tin oxide nanoparticles are produced by full or partial PVD or CVD coating. This requires structuring and masking processes during coating.

The use of wet chemical printing processes for ITO coating is an alternative, very economical process and can be carried out using the sol-gel method or ITO nanoparticle dispersion. Other associated microelectronic and optoelectronic applications: RFID tags / chips, solar cells, sensors, fuel cells, electrolytic capacitors, lithium polymer batteries

According to the invention, the substrate material described under 3a. plastic materials listed used as a carrier film for the metallization.

The following metals / semimetals (e.g. alkali metals) or alloys and combinations of these metals and chemical compounds, such as e.g. polymeric compounds with these metals, used as electrical conductors in the field of micro and optoelectronics: boron (B), barium (Ba) cadmium (Cd), cobalt (Co) cesium (Cs) silicon (Si), germanium (Ge), arsenic (As), Selenium (Se), Antimony (Sb), Tellurium (Te), Polonium (Po), Tin (Sn) Astat (At), Lithium (Li), Phosphorus (P) iodine (I), Bismuth (Bi ) Tin (Sn) Chemical compounds such as Titanium dioxide (TiO2) gallium arsenide (GaAs) gallium nitride (GaN), indium antimonide (InSb) zinc selenide (ZnSe) cadmium sulfide (CdS) such as copper (II) chloride, alloys of calcium-aluminum-barium, ruthenium-magnesium-silver, lithium fluoride, cesium fluoride , Aluminum tris (8-hydroxyquinoline), Alq3. and transparent conductive oxides (TCOs), especially indium tin oxides (ITO)

The plastic films and plastic materials described under 3a can also be equipped and combined with electrically conductive polymers (polymer electronics) .These are electronic circuits made of electrically conductive polymers, on carrier materials made of preferably organic films, and with conductor tracks and components made of conductive organic molecules (organic semiconductors) Part of the composite layer (B). These are polymers (especially organic semiconductors) that are oxidatively or reductively doped with chemical metal / semimetal compounds, e.g. Polyacetylene with arsenic pentaflouride or iodine.

Further examples of conductive polymers are doped polypyrrole, polyphenylene sulfide, polythiophene and organometallic complexes with macrocyclic ligands such as phthalocyanine.

Oxidative doping is achieved with arsenic pentafluoride, titanium tetrachloride, bromine or iodine, while reductive doping is achieved with sodium-potassium alloys or dilithium benzophenonate. Applications from polymer electronics: organic light emitting diode, organic solar cell, organic field effect transistor / thin film transistor. The molecules (in addition to monomers and oligomers, especially polymers) are in Form of thin films or small volumes printed, glued or otherwise attached to the films. These films are produced preferably by thin-film technology (for example by PVD, CVD, OPVD (organic vapor deposition) processes or also by conventional printing techniques (inkjet, offset printing, gravure printing, screen printing, micro-contact or even by rotary coating. Preferred layer thicknesses for micro-opto and electronic conductive coatings, as well as electrically conductive polymers: 1 nm (nanometer) to 1 µm thick ..

Preferred embodiment: universal applications

The use of the display element is universally intended for use as a device and / or component element, the use preferably being for an element for use as a packaging, watch, jewelry, clothing, accessories, vehicle identification, traffic sign -, advertising sign, picture frame, floor, wall, ceiling, furniture, decoration, interior construction element, preferably strip, profile, edge, door and / or window element, facade, wallpaper, car Interior, car exterior, household appliance, electrical appliance and / or outdoor covering element.

Transparent, single or multi-layer upper layer (3)

For universal use, it is advantageous in many applications to provide a protective layer for the electrically controlled display element, which protects the display element from mechanical stress, i.e. against impact, abrasion, scratching, as well as moisture and dirt.

The following embodiments show which solutions are provided according to the invention for this purpose, the protective layer being designed as a transparent single or multi-layer cover layer (3).

The transparent single or multi-layer cover layer (3) can be made from e.g. Plastic film (s) (3a) and / or surface finishes (3b) consist of or combinations of (3a) and (3b). For example. it is also possible to provide only a surface finish (3b) without using a plastic film (s) (3a). Likewise, only a plastic film can be used without surface finishing. The surface finish (3b) can e.g. also as an outer layer on the plastic film (3a) or directly on the layer of metallic material (1). The plastic films in the definition of this invention can also be in the form of molten plastic, e.g. applied as a molten polymer to form the transparent single or multilayer top layer, e.g. by calendering or casting. This has the advantage that e.g. while the plastic has not yet hardened, a surface structure is e.g. can be embossed into the surface using an embossing calender, e.g. a wooden pore. Likewise, a surface structure can also be embossed into a plastic film if the plastic film is heated before the embossing process and the plastic melts, so that the structure is embossed into the not yet hardened plastic surface. In principle, the foils can be used over their entire surface or in part. In most applications, it makes sense to provide the transparent single-layer or multilayer upper layer in order to ensure good abrasion and scratch resistance. With less stressed areas, e.g. This layer can also be omitted from ceiling cladding. The layers described in 3., 3a and 3b are basically also suitable for the surface protection of metallized textiles, fabrics or nonwovens. (e.g. aqueous PU coating, or lamination, e.g. flame lamination, sprinkling of meltable, powdered plastics and subsequent melting)

a. Plastic films and / or molten polymer (3a)

- Plastic as a transparent film, preferably elastic films

The upper layer can be constructed in one or more layers. The multilayer structure (two or more films) has the advantage that each film, and / or also melted polymer layer, can be provided with special performance properties, depending on the application. Different plastics and their advantageous properties can be combined with one another for the individual film layers. Basically, plastics based on synthetic and / or semi-synthetic polymers and / or biopolymers, such as thermosets and thermoplastics, are used. A thermoplastic and / or elastomeric plastic or thermoplastic elastomer is preferably used for the film layer (s), preferably PVC, also as cast PVC or polyester, polyethylene (PE), polyester with PVC surface, polyurethane (PUR) and thermoplastic polyurethane (TPU) ), Polypropylene (PP), cast propylene (CPP), oriented propylene (OPP), biaxial oriented propylene (BOPP), polystyrene (PS), and / or polyethylene terephthalate (PET) biaxially oriented polyester film (BOPET) polyester (PES), polytetraflourethylene ( PTFE), high density Polyethylene (HDPE), Low Density Polyethylene, (LDPE), polyamide (PA), polyethylene terephthalate (PET) or polystyrene (PS), polylactide (PLA or PDLA or PLLA or PDLLA), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polycarbonate (PC) polyethylene naphthalate (PEN), polycarbonate (PC), polyester carbonate (PEC), polyarylate (PAR), unsaturated polyester resin (UP), cast alkyd resin film, cast acrylic resin layer, polyimide (PI), PEI, polyether sulfone (PES) polyethylene naphthalate (PEN) , PETP or Kapton, polyether ketones such as PAEK and PEEK, cellophane and acetate or combinations of these plastics.

Alternatively, biopolymers can also be used. Bioplastics can be made from a variety of plant and animal raw materials. The most important raw material suppliers are wood (cellulose and lignin), cereal plants and potatoes (starch), sugar cane and sugar beet (sugar) as well as oil plants (vegetable oils) and e.g. Insects (chitin shell and crab shells). Cellulose-based plastics include: celluloid, cellophane, viscose and lyocell, as well as cellulose acetate and lignin-based biopolymers with the addition of e.g. of natural fibers from hemp or flax and cellulose-based biopolymers z. B. made of cotton. Modified cellulose using enzymes can also be used as a biopolymer. Starch-based biopolymers are obtained from corn, wheat, potatoes, as well as sugar cane and sugar beet. These include thermoplastic starch (TPS) polylactic acid or polylactide (PLA), polyhydroxyalkanoates such as polyhydroxybutyrate, polyester or thermoplastic biopolyesters such as polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) and polyethylene furanoate (PEF). Fatty acids can be obtained from vegetable oils, which are converted into high-quality bioplastics via several chemical intermediates. Vegetable oil-based plastics are biopolyamides (Bio-PA) and biopolyurethanes (Bio -PU). Other raw materials for biopolymers are casein, a protein from milk, gelatin, a protein from animal bones or skin and chitin, a polysaccharide from fungi, insects (chitosan), crab shells. PHB (extracted from bacteria), zein and algae. Biopolymers are ecologically sustainable because the raw materials for them are renewable (not petroleum-based) and biodegradable. In principle, polymeric and / or biopolymeric material mixtures made of the plastics mentioned above can also be used.

The polymers and biopolymers mentioned above can in principle be used in the form of a plastic film for metallization.

Mixtures of one or more of the aforementioned plastics can also be used. The plastic films can be produced by extrusion or also by casting, calendering or blow molding. In the blow molding process, several films with different properties can be co-extruded to form a film composite. Optionally, these films can be self-adhesive coated with polyacrylate adhesive for adhesive lamination. The film thickness of a film layer is between 20 µm and 2500 µm, preferably between 20 µm and 500 µm, in particular 20-150 µm

Currently commercially available film materials for printing the decorative layer in accordance with point 2.e are e.g. PVC, polyester, such as BOPET, PP and polyamide

A very simple and economical embodiment is as follows: Here, the upper layer consists of only one film, which has printed electronics on the underside. It is advantageous to equip the film for printing with a transparent printing / ink / color recording layer. The plastic material used must have the abrasion, scratch and wear resistance appropriate for the application. If two foils are used as a layer structure, the printing of the electronics can be arranged on the underside of the uppermost foil layer and / or on the top side of the lower foil layer.

In addition, the above-mentioned layer composite can also be designed as a preliminary product in the form of a firmly connected layer composite. (See preferred embodiments 1.

The connection of individual film layers is referred to below as a composite film.

The individual film layers are usually extruded or laminated or laminated. The composite film is produced by laminating several layers of the same or different materials or layers, in this case plastic films which correspond to the layer structure according to the invention, with the aid of suitable laminating agents (lacquer, glue, wax). Laminating is carried out in order to protect and / or decorate and / or to add favorable material properties by applying the material on or under a layer with the desired properties or by placing it between two layers. In order to print, glue and coat / coat the plastic film, most of the above-mentioned plastic materials (e.g. PE, PP, PET) require corona pretreatment. The surface to be treated is exposed to an electrical corona discharge for a short time. Alternatives for corona treatment are flame treatment, plasma treatment and fluorination. Processing is preferably carried out on a roll (roll laminating machine) or as surface lamination. (Surface laminating machine)

A distinction is made between lamination, wet and thermal lamination. In wet lamination, a viscous polyurethane-based dispersion adhesive is applied to the film in layers of 7-25 µm and first dried in a drying device. The adhesive is often two-component. The printing material is fed in and combined with the film under pressure in a nip. Then the adhesive hardens. In dry lamination, the layer composite is created with a dry adhesive. predominantly 2-component reactive adhesives matched to the respective substrates are used for lamination. The application techniques of the laminating systems are preferably provided via kiss coating, anilox roller application, nozzle and casting box principle, with application weights preferably from 1 g / m ² to 20 g / m ^2. For thermal lamination, the film is precoated with a thermoactive adhesive. This is melted by heat and combines the different materials under the influence of pressure.

The composite film can also be produced by lamination. In hot lamination, a full-area bond of the layer structure according to the invention is achieved on both sides under the action of pressure and heat (60-120 ° C.). The possibility of combining the film thickness and the mass per unit area of the metallized paper / plastic film allows both flexible, still rollable and rigid end products.

In cold lamination, the films are coated with an adhesive that has normal adhesive properties at all temperatures. In the connection between paper / film and film, the adhesive acts like a double-sided adhesive tape.

In addition to the aforementioned processes, the film layer (s) including the metallic layer and a carrier plate and counter-pull can also be carried out in one process step, e.g. thermally bonded together, e.g. by hot pressing and / or hot gluing, for example with a hot press or hot melt press or short cycle press.

Another method for connecting plastic and metal is thermal direct joining, the metallic layer being electrically heated by resistance heating. If this is then brought together with the plastic layer, the plastic melts and forms a firm bond with the metal immediately after solidification.

In this context, it is particularly advantageous that the upper layer has a PUR film layer on the underside as an adhesion promoter to the backing layer. PUR is characterized by the fact that this material has a low melting point, so that this plastic melts during thermal bonding and thus serves as an adhesive layer / adhesion promoter between the other layers of the top layer and the metallic material.

The plastic films can have a structure on the outer wear layer that is produced, for example, by embossing. This allows surface structures, e.g. Make wood or stone structures.

Another embodiment is to form the film layer as a transparent melamine layer. Here, for example, one or more transparent overlays can be applied to the printed electronics. The printed electronics can then e.g. on the bottom or top of the overlay. The connection of the overlay to the carrier layer / carrier plate is preferably carried out by thermal bonding, i.e. Hot pressing, e.g. via a short-cycle press device (KT press) and / or gluing or hot gluing.

Likewise, the composite film according to the invention can be provided on the underside with a melamine-coated paper. This has the advantage that the composite film can be pressed in a KT press, for example on a wooden material (HDF, MDF). The pressing takes place under pressure and heat, at temperatures of 160-200 degrees Celsius. The melamine becomes liquid in the resin-coated paper and combines with the HDF carrier board through the pressing process. The melamine-coated paper takes on an adapter function for processing the composite film in a KT press. The prerequisite for technical feasibility is the use of a composite film according to the invention, which is temperature-resistant in the range of 160-200 degrees Celsius. This means that the individual components of the composite film, such as plastic and Laminating adhesive must meet this temperature requirement. The melting range of polypropylene (PP) is approx. 160 - 165 degrees Celsius, polyethylene terephthalate (PET) has a melting point of 250-260 degrees Celsius, polyurethane has a melting point of 190 degrees Celsius.

The transparent single-layer or multi-layer cover layer is preferably provided in a crystal-clear design so that the printed electronics come into their own. However, it can also be provided that the transparent single or multi-layer cover layer has a targeted, translucent coloration, e.g. as a milky, whitish color. As a result, the transparent single or multi-layer cover layer can be made optically more matt. This can also be created by using translucent and / or translucent colors.

b. Surface Equipments (3b)

This includes transparent surface finishes and / or impregnations (e.g. for fabrics, nonwovens, textiles), preferably transparent polymer coating systems and / or oil and / or wax coatings based on natural products.

Transparent, highly durable and / or low-odor coatings based on a thermoplastic and / or elastomeric plastic are preferred. Preferred plastics: PUR and / or PLTR and / or PVC and / or PP and / or PE- A water-thinnable, transparent PUR lacquer has special advantages, with optional additives such as Polyurethane dispersion, silica, water, glycol ether, heterocyclic ketones and / or additives. Also acrylic varnishes, EB acrylate and impregnations, elastic varnishes, polyester varnishes (PES), e.g. Can be used in the stoving process or ESH paint. Other paint systems that can be used: alkyd resin paints (air drying or heat drying), emulsion paints, paints and varnishes based on acrylic polymers, high solids (wet paint systems based on organic solvents), phenolic, urea and melamine resin paints (aqueous or solvent-based) polyester paints, polystyrene and polyvinyl resin paints, Polyurethane resin paints, powder paints, silicone resin paints, paints and varnishes based on natural polymers (biopolymers, see explanations under 3a.), Paints based on synthetic polymers, cellulose nitrate paints. Preferred surface finish thickness from 1 µm to 1000 µm. The surface finishes can also be structure-forming, i.e. have a surface structure, e.g. around a decorative look, e.g. To create wood pores or decorative plastic structures or to achieve a functional property, e.g. Slip resistance. The surface finish can be applied both directly to the layer of printed electronics, dispensing with the plastic films described under (3a) and / or on the top as an outer wear layer on the plastic films described under (3a), or between the films on the top or bottom, e.g. as an adhesion-promoting layer.

• 1. Vernetzende wässrige Beschichtungen
  • a) UV-vernetzende wässrige Beschichtungen
    • - Physikalische Trocknung durch Wärme in Trockenkanälen und/oder durch Infrarot- strahlung
    • - Chemische Vernetzung durch ultraviolette Strahlung (UV)
    • - Typische Trockenschichtdicke 8 - 15 µm
  • b) Hitze-vernetzende wässrige Beschichtungen
    • - Chemische Vernetzung durch hoheTemperaturen in Trockenkanälen
    • - Typische Trockenschichtdicke 8 - 12 µm
  • c) Zweikomponentige wässrige Beschichtungen
    • - physikalische Trocknung durch Wärme in Trockenkanälen und / oder Infrarotstrah- lung
    • - chemische Vernetzung durch die Härterkomponente
    • - Typische Trockenschichtdicke 5 - 20 µm
• 2. Vernetzende 100% - Systeme (Festkörpergehalt)
  • - Chemische Vernetzung und Härtung zum Beispiel durch ultraviolette Strahlung (UV)
  • - Typische Trockenschichtdicke 10 - 25 µm in Zweischichtaufträgen auch bis 35 - 40 µm
• 3. Thermisch trocknende wässrige Dispersionen (nicht vernetzt)
  • - Physikalische Trocknung durch Wärme in Trockenkanälen und/oder durch Infrarot- strahlung
  • - Verwendung meist als temporäre Beschichtung
  • - durch Grundreiniger entfernbar
  • - Typische Trockenschichtdicke 5 - 12 µm

For surface finishing, for example, the following methods come into question, which differ in characteristic features and can generally comprise layer thicknesses of 5 μm to 40 μm.

• 1. Crosslinking aqueous coatings
  • a) UV-crosslinking aqueous coatings
    • - Physical drying by heat in drying channels and / or by infrared radiation
    • - Chemical crosslinking through ultraviolet radiation (UV)
    • - Typical dry layer thickness 8 - 15 µm
  • b) heat-crosslinking aqueous coatings
    • - Chemical crosslinking through high temperatures in drying tunnels
    • - Typical dry layer thickness 8 - 12 µm
  • c) Two-component aqueous coatings
    • - Physical drying by heat in drying channels and / or infrared radiation
    • - chemical crosslinking through the hardener component
    • - Typical dry film thickness 5 - 20 µm
• 2. Crosslinking 100% systems (solids content)
  • - Chemical crosslinking and curing, for example by ultraviolet radiation (UV)
  • - Typical dry film thickness 10 - 25 µm in two-coat applications also up to 35 - 40 µm
• 3. Thermally drying aqueous dispersions (not crosslinked)
  • - Physical drying by heat in drying channels and / or by infrared radiation
  • - Mostly used as a temporary coating
  • - Removable with basic cleaner
  • - Typical dry layer thickness 5 - 12 µm

Preferred embodiments

Figure 1 Prefabricated composite layer according to the invention, as a basic layer structure

The following explanations apply to the 1 :

4. The layer structure of the electronically controlled display element according to the invention provides a layer (1) with the electronic element (E), which is optionally embedded in a filler layer, which can be produced, for example, by printing. (1) with the display element (2 ), for example produced by printed electronics based on OLED and / or micro LED and / or electronic ink and an optionally transparent single or multi-layer upper layer (3). is preferably produced as a prefabricated composite layer (A). This can then be processed as a composite product, for example. Preferred thickness of the composite layer: 1 µm 2500 µm.
These composite layers can then be applied to a carrier layer (5), for example during further processing. In principle, the composite layer can be applied to any suitable carrier layer or any substrate. The carrier layer (5) preferably consists of the following materials: paper, cardboard, plastic, laminate (HPL, CPL DKS), plastic film, elastomer, rubber, foam, metal, textile, fabric or fleece, wood, wood materials, WPC, cork, linoleum , Metal, stone-based, porcelain stoneware-based, mineral, ceramic, cement-based, gypsum-based substrates and / or materials or glass, in particular also gypsum plasterboards, gypsum fibreboards, plaster substrates and OSB, HDF, MDF, chipboard or combinations of these materials . The carrier layer (5) can also be constructed heterogeneously and / or in one or more layers.

In the prefabrication, the layers (1-4) are joined to form a composite layer (A), preferably by lamination with a roll lamination machine, (thermal lamination or wet / dry lamination), lamination (see details under 3a.), Thermal bonding and / or gluing / Hot glue or thermal direct joining, or with the help of double-sided adhesive films. The plastic films in the definition of this invention can also be in the form of molten plastic, e.g. applied as a molten polymer to form the transparent single or multilayer top layer, e.g. by calendering or casting. The connection to the carrier layer can be made using the same previously mentioned methods, preferably by surface lamination on a surface lamination system.

It is advantageous if the composite layer (A) optionally has an underside layer (4) as an adhesion promoter layer and / or a self-adhesive layer to the carrier layer (5). The adhesion promoter layer can be provided as in the embodiments described under (3a) and (3b).

The underside layer (4) can also perform other functions, such as as a leveling layer to compensate for unevenness in the carrier layer. This is advantageous for the surface of wood-based materials that "telegraph" through the composite film due to their roughness, irregularities or unevenness. Furthermore, the underside layer (4) can also be a protective function for the layer made of printed electronics in order to protect it from moisture and mechanical stress in the processing process (damage to the metal layer, for example by scratches).

The underside layer (4) can also take on a damping function in order to improve, for example, the acoustic properties of the surface, such as the impact sound for floor coverings.

In addition, the underside layer (4) can also be formed as an adapter layer for a specific carrier layer. Example: Training as melamine-coated paper for pressing onto wooden materials in a short-cycle press or as a paper / non-woven layer for gluing with paste on a plaster surface.

This embodiment is, for example, for the application area of wallpapers, decorative papers, decorative films and edging material in the form of a prefabricated composite film or for lamination to any one Carrier layer provided. For the connection of the layer structure according to the invention to the carrier layer, the rest apply under 3.a. mentioned explanations on the subject of lamination and lamination. A particularly preferred area of application is the production of printed decorative papers / foils, printed decorative foils, finish foils (finished surfaces) and melamine films for the wood-based panel and furniture industries with the application areas of flooring, furniture, interior fittings and caravans. Composite films of this type can also be used for 3D applications and components, such as, for example, as wrapping, deep-drawing or postforming films.

The use of a composite film with printed electronic ink and / or the use of an e-paper also has the advantage that a so-called bistable display state arises, i.e. the last picture can still be seen when the power supply has ended. With such displays, electricity is only required when the picture is changed. A preferred embodiment of the E Paper is the use of an electrolytic foil with the use of electrochromic molecules. Patterns can also be embossed into such a film. The preferred thickness of such a film is less than 0.5 mm, in particular 0.3 mm, the film being highly flexible, i.e. flexible, flexible and rollable.

Figure 2: embodiment as a composite film (A)

The following explanations apply to the 2nd

Exemplary embodiment as a composite film (A)

This preferred embodiment additionally has a technology layer (T), e.g. for the application of electrical conductor tracks, preferably produced by printing with metallic or metal-containing material. The power supply for the display element and the electronic element can be produced with this. The technology layer also serves for the optional accommodation of a battery and / or a rechargeable battery for the power supply, the power supply, preferably wireless and / or wired on a technical basis, being connected to the power supply system and / or a rechargeable battery and / or induction current and / or by radio current or is generated by radio current and / or by ultrasound transmission, preferably using piezotechnology-based sensors. With the induction principle, a transmitter based on a magnetic dipole coil is preferably used, with radio current based on a secondary coil. Optionally, the power supply / electronics and battery technology can also be outsourced to an external connection box or integrated into component elements.

A filler layer (F) is optionally arranged between the conductor tracks as an insulation and compensation layer, so that unevenness caused by the cross section of the conductor track does not become visible on the surface. The filling layer (F) can be used e.g. as a coating with an insulating material (preferably plastic), e.g. by printing or varnishing, or by a separately applied masked negative layer.

Figure 3: Blockchain cloud according to the invention for use by the road traffic authority for digital license plates

Figure 4: Digital license plate according to the invention

The following explanations apply to the 3rd and 4th :

Preferred embodiment: digital license plate

A very innovative preferred field of application of the invention is the use of a display element, preferably for an element as an official identification for a vehicle, preferably for a car, truck, bus, two-wheeler, motorcycle, e-bike, e-scooter, caravan, utility vehicle, trailer, tram , Train, aircraft, in particular an airplane, a helicopter and a ship.

The state of the art for vehicle license plates essentially consists of the identification of a vehicle by means of a sheet metal number plate, mostly in the size 520 x 110 mm. This state of the art has not changed significantly since the development of the first cars in automotive history. The label contains the following information: vehicle registration number, country code, TÜV / HU sticker and the city / district / country sticker.

The license plate is usually attached to the front and rear of the vehicle. License plate lighting on the vehicle is mandatory for the rear license plate.

Comparing the state of the art of today's automobile and contemporary service offers for mobility, such as Electromobility, autonomous driving, driving aids, traffic control, car sharing on-board computer, LED lighting technology, etc., the tinny plate looks like an ancient relic from the analogue age of our grandfathers. In addition, based on today's automotive design, it is an ugly, unaesthetic, unworthy foreign element on a modern, designed car, such as on the Alfa Romeo, where the license plate is also asymmetrically arranged in the front area.

The official processing at the road traffic offices for registration and deregistration of vehicles that require a personal appearance of the car owner or car dealer is bureaucratic - time and cost intensive and does not correspond to the organizational and processing options of the digital age. To make matters worse, the promotionalist organizational principle of Germany, with the many decentralized road traffic offices of the cities and districts of the individual federal states, and a decentralized data and information management and storage.

The inventor set himself the task of developing a fundamentally new concept for this problem, using all the possibilities of the digital age.

The slide on page 19 provides an overview of the overall concept.

The basic idea is to establish a nationwide blockchain cloud for the road traffic authority (STVB) controlled and controlled by the individual road traffic authorities (STVA), which have data sovereignty. In this blockchain cloud, all data of all relevant user groups relating to the topic of mobility are stored and are continuously checked and updated. There are defined access and transaction permits for the individual user groups, which are transmitted to the cloud using a software / app on a smartphone.

Examples of user groups are STVA, driving license office, vehicle tax, points account / fine, vehicle insurance, TÜV, police, traffic control, vehicle owner, vehicle dealer, vehicle manufacturer, automobile clubs, etc.

Furthermore, the inventor proposes to equip each vehicle with a digital license plate. It is a preconfigured, electrically controlled display element with an integrated electronic element. This digital vehicle sign is directly controlled by the blockchain cloud via a wireless connection via the computer network of the STVB.

In other words, every digital vehicle license plate has a screen display on which the vehicle license plate and other information are shown graphically, this information via a STVB's own state radio network, preferably based on 3G / $ G / 5G with its own protected channel bandwidth, from the blockchain cloud be sent directly to the digital vehicle sign and in this way approvals and de-registrations are processed.

To identify the license plate number, the screen display has an electronic element, e.g. in the form of a 3-5 G Simcard that is secured with an encryption code. Each digital number plate has its own ID code, which is assigned to the chassis number of the vehicle.

The digital license plate also establishes a connection to the vehicle's on-board computer and enables defined access and data exchange with the on-board computer through the STVB blockchain cloud.

The principle of the blockchain cloud enables secure encrypted data storage and data management. The above ID code consists of a character code of at least 8 characters, a character space of at least 89 characters. This results in a combination possibility of 8 to 89, which is infinite in the mathematical result and thus makes a hacker attack using the brute force method impossible.

• Anzeigeelement dadurch gekennzeichnet, dass das elektronische Element eine digitale Verknüpfung mit einer IT-Infrastruktur über ein Rechnernetz aufweist.
• Anzeigeelemennt dadurch gekennzeichnet, dass die IT-Infrastruktur ein verschlüsseltes Buchführungssystem und / oder Verfahren aufweist.
• Anzeigeelement dadurch gekennzeichnet, dass das elektronische Element mindestens einen Verschlüsselungscode aufweist und/oder mit mindestens einem Verschlüsselungscode digital verknüpft ist.
• Anzeigeelement dadurch gekennzeichnet, dass der Verschlüsselungscode aus mindestens acht Zeichen besteht, basierend auf einem Zeichenraum von mindestens 89 Zeichen.
• Anzeigeelement dadurch gekennzeichnet, dass der Verschlüsselungscode in der IT -Infrastruktur gespeichert ist.

In summary, this results in the following technical designs according to the invention:

• Display element characterized in that the electronic element has a digital link to an IT infrastructure via a computer network.
• The display is characterized in that the IT infrastructure has an encrypted accounting system and / or method.
• Display element characterized in that the electronic element has at least one encryption code and / or is digitally linked to at least one encryption code.
• Display element characterized in that the encryption code consists of at least eight characters, based on a character space of at least 89 characters.
• Display element characterized in that the encryption code is stored in the IT infrastructure.

The slide on page 20 shows a particularly preferred embodiment of the digital identifier.

The digital license plate is compatible with common license plate holders. It has an integrated interface or adapter plug connection for connection to the car battery and is operated on a 12 V basis. For this purpose it is necessary to provide a cable connection from the car battery to the front and rear license plates. In addition, the display contains an internal battery and / or rechargeable battery if the vehicle power supply fails, which means that an emergency power supply of e.g. 10 hours possible The front and rear license plates can be connected wirelessly via Bluetooth and / or via a cable connection. The display is in permanent operation, optionally the display can also switch off automatically at night.

Display contents are automatically sent from the STVB Blockchaincloud to the vehicle license plate display after acquisition of the master data of the vehicle and updated continuously. The regionally responsible road traffic authority, i. E., Has sole, authorized access for the digital display. this is where the data sovereignty controls, controls, updates, or deletes the digital license plate.

The Road Traffic Office will in future be the central, data-sovereign communication and coordination point between the different user groups, i.e. All relevant information from the user groups is initially sent to the authorities as information, where it is centrally recorded, checked, saved and continuously updated. Examples: TÜV inspector reports HU extension, police reports technical defects in the vehicle, owner reports change of liability insurance etc.

In addition, the digital license plate and the digital networking of information from the various user groups result in numerous new additional functions and new application options. This leads to a new level of efficiency not only for the road traffic offices, but for all user groups involved. An overview of the main advantages and possibilities of the overall concept follows.

New applications and additional functions

In addition to the basic functions, completely new additional functions can also be implemented in the future, e.g. a nationwide traffic control system via the GPS recording of the digital license plate or by networking with the on-board computer of the vehicle, the road traffic office can check compliance with environmental regulations, such as Activate fuel consumption values, exhaust gas values, according to the manufacturer's energy consumption labeling or driving bans for certain zones, or carry out safety-related controls such as speed control, seat belt duty, distance control ... etc. Set via GPS function with automatic fine delivery or shutdown of the vehicle (e.g. display completely red with text: "Out of service"). An international data exchange between individual countries will be possible in the future via the central digitization of vehicle data. possible across Europe and / or can be standardized across Europe / worldwide. (Automotive cloud as storage)

Advantages for road traffic offices (STVA)

• a. Significant improvement in the performance and efficiency of the road traffic authorities:
• b. Rapid processing of vehicle registrations through exclusive online communication with relevant users, such as car owners, car dealers ... etc. Personal appearance in the Road traffic office no longer necessary. Registration of a vehicle is active in a few minutes. centralization
• c. Reduction in administrative costs.
• d. Additional new tasks / area of competence
• e. In future, personnel will take over communication and control functions, such as Environment / safety etc., instead of reducing staff

In addition, pioneering new control functions and control options for the STVA arise in the areas of safety, environment, traffic control, traffic safety, autonomous driving, through online access to camera / video (live cam) and sensor functions of the digital vehicle, as well as defined access to on-board computers. Car traffic entails external costs, particularly in the area of pollution and consequential accident costs. Measures taken by the STVA to increase traffic safety can help to reduce the number of people killed in a traffic accident. Furthermore, the secondary costs of all road users can be reduced, such as accident and environmental costs (noise, air pollutants) that would otherwise be borne by the general public.

Both automobile manufacturers and suppliers as well as companies from the IT sector, in particular Google research and development on autonomously driving motor vehicles. The invention can make a significant contribution to promptly solving this entire issue.

Topics such as parking guidance systems, car park occupancy and networking with car sharing offers can also help to relieve the inner cities in terms of traffic and optimize traffic flow. The digital vehicle solves the current problem of labeling a carsharing vehicle, since this can be identified, for example, by another license plate color on the display.

In future, the STVA will monitor compliance with data protection regulations and will regularly delete old data.

• - Polizeikontrolle Über App möglich. Polizei kann sämtliche KFZ und KFZ Halter Informationen abrufen, z.B. Fahrzeugpapiere: Fahrzeugschein, Füherschein ist digital hinterlegt in App, Durchführung von Fahrzeugkontrollen,:polizeilich gesuchte Fahrzeuge, TÜV Kontrolle, Geschwindigkeitskontrolle , Fahrzeugsicherheit, GPS Ortung von Fahrzeugen. Mängelanzeige KFZ, Stillegungsinfo an Strassenverkehrsamt, Bussgeldinfo
• -Führerscheinkontrolle/ Fahrer muss sich zukünftig in Fahrzeug einloggen dadurch wird Führerscheinstatus, Punkte in Flensburg , Führerschein wird digital hinterlegt in App
• -Kontrolle: Einhalten von Fahrpausen / vorgeschriebenen Pausen ,Fahrtenbuch wird gespeichert, Fahrten Buchfunktion, Fahrtenschreiberfunktion: Überprüfung und Kontrolle von Fahrtzeiten. Automatischer Hinweis auf Fahrpausen auf Bordcomputer
• -Diebstahlschutz. Codierung Fahrgestellnummer und Kennzeichen, bei nicht Übereinstimmung:: Fahrsperre aktivieren
• -Kontrolle der Gurtpflichterfüllung durch Vernetzung mit Bordcomputer über Bluetooth, automatische Meldung bei Verstoss, mit Bussgeldbescheid
• -Kontrolle Telefonierverbot mit Mobilphone während der Fahrt über Verbindung mit Bordcomputer, automatische Meldung bei Verstoß, mit Bussgeldbescheid
• -Online Kontrolle des STVA Lichtanlage und Bereifung, Profiltiefe Sommer/ Winterreifen
• - Pannenhilfe ,SOS Funktion, Notruf, Stau : auf dem Display erscheint entsprechender Text, Blinkfunktion etc. Durchsagen über Bordlautsprecher, Stau, Umleitungen, SOS....
• - automatische Erkennung von Geschwindigkeitsüberschreitungen per GPS inclusive Bussgeldbescheid
• -Abstandsmessung zum Vorderfahrzeug über Sensor/ inclusive Bussgeldbescheid bei Verstoss
• -Mautinformationen : Automatische Erfassung und Abbuchung von Mautpflichtigkeit Speicherung aller relevanten Stammdaten von KFZ Halter/ KFZ Händler/ KFZ/ TÜV Hersteller :Fahrzeugschein, Fahrzeugbrief, Führerschein , Fahrzeug, Austattung, Betriebsanleitung, Reparaturhistorie Versicherungsstatus, Haftpflicht, Kasko ,TÜV TÜV kann durch App Prüfsiegel aktualisieren, separater Zugriff nur auf TÜV bereich,
• -Kontrolle und Belohnung defensives Fahren und Teilnahme Fahrsicherheitstraining, Auswertung Fahrverhalten über Bordcomputer, Belohnung :Senkung der KFZ Steuer und Versicherungsbeiträge... Kosten für den Fahrzeughalter senken
• -Individualisierung des Kennzeichens z.B. individuelle grafische Gestaltung ,z.B. Auswahl von verschiedenen grafischen Hintergründen
• - Zusatzfunktionen KFZ Display: Anzeige von Verkehrsinformationen, Gefahr, Stauende, Pannenhilfe, Kommunikation mit anderen Verkehrsteilnehmern....
• -Vorteil für Fahrzeughersteller: Intergration des digitalen KFZ Zeichens in Karosseriedesign bei Neuentwicklungen der Autohersteller, neue Designmoöglichkeiten durch flächenbündige Integration in die Karosserie-Aussenhülle,dadurch diebstahlsicher, Bei Neuentwicklungen kann Position, Format, Form und Grösse des Kennzeichens variieren
• -Kennzeichen bei Dunkelheit erkennbar, digitales KFZ Display leuchtet Tag und Nacht durchgängig, geringer Stromverbrauch und / oder ohne Strom durch bistabilen Displayzustand mittels elekrronischer Tinte, Bessere Erkenn -und Lesbarkeit des Kennzeichens, Mehr Informationen und Zusatzinformationen ablesbar
• - Die Kennzeichenbeleuchtung am Heck des KFZ entfällt
• - Display ist kompatibel und nachrüstbar für konventionelle Kennzeichen Halterungen,
• -Vermeidung von Metallschildern, die im Lebenszyklus durchschnittlich bis zu 5 × gewechselt werden
• - digitales KFZ Schild ist fälschungssicher durch doppelte GPS Funktion, d.h. von GPS Bordcomputer und GPS des digitalen Kennzeichens , bei Entfernung des KFZ Zeichens wird abweichende GPS Ortung erkannt und automatisch an STVA gemeldet und automatische Mitteilung an Polizei
• - Personenerkennung über Sensor/ Kamera
• -Diebstahlsicherungsfunktion: Fahrzeugzugriff und Fahrfunktion nur durch Einloggen des Fahrers möglich oder Zugriff nur durch definierten Fahrer- Personenkreis Codierung ob Fahrzeug fremdgeöffnet wurde, GPS Ortung von gestohlenen Fahrzeugen
• - Akustische und optische Signale bei Diebstahlversuch, automatische Kameraaktivierung und automatische Bildversendung bei manipulationen am KFZ Schild, Meldung an Polizei
• - Verkehrslenkung durch eingebaute GPS Erkennung, aktuelle Infos an Bordnavi, automatische Navisteuerung, Verkehrsleitsystem, Stauminimierung
• - Parkleitsystem , Parkhausbelegung, Vernetzung mit Car sharing Angeboten Vernetzung mit Car sharing Angeboten

The following is a sample listing of the new options:

• - Police control possible via app. The police can call up all vehicle and vehicle owner information, e.g. vehicle documents: vehicle registration, driver's license is stored digitally in the app, vehicle checks are carried out: vehicles searched by the police, TÜV inspection, speed control, vehicle security, GPS location of vehicles. Defect notification vehicle, decommissioning information to road traffic office, fine information
• -Driver's license check / driver will have to log into the vehicle in the future, this will result in driver's license status, points in Flensburg, driver's license will be stored digitally in the app
• -Control: Adherence to driving breaks / prescribed breaks, logbook is saved, trips book function, tachograph function: checking and checking travel times. Automatic notification of breaks on the on-board computer
• -Theft protection. Coding of chassis number and number plate, if they do not match: activate the driving lock
• -Control of the fulfillment of seat belt obligations through networking with on-board computer via Bluetooth, automatic notification of violation, with notice of fine
• -Control of no calls with mobile phones while driving via connection with on-board computer, automatic notification in the event of violation, with notice of fine
• -Online control of the STVA lighting system and tires, tread depth summer / winter tires
• - Roadside assistance, SOS function, emergency call, traffic jam: the text, flashing function, etc. appears on the display. Announcements via on-board loudspeakers, traffic jam, diversions, SOS ....
• - Automatic detection of overspeeds via GPS including a fine
• -Distance measurement to the vehicle in front via sensor / including a fine for a violation
• - Toll information: Automatic registration and debiting of toll liability Storage of all relevant master data from car owner / car dealer / car / TÜV Manufacturer: vehicle registration, vehicle registration document, driver's license, vehicle, equipment, operating instructions, repair history, insurance status, Liability, comprehensive insurance, TÜV TÜV can update with the app seal of approval, separate access only to TÜV area,
• -Control and rewarding defensive driving and participation in driving safety training, evaluation of driving behavior via on-board computer, reward: reduction in vehicle tax and insurance premiums ... lower costs for vehicle owners
• -Individualization of the license plate, e.g. individual graphic design, e.g. selection of different graphic backgrounds
• - Additional functions vehicle display: display of traffic information, danger, traffic jam end, breakdown assistance, communication with other road users ....
• Advantage for vehicle manufacturers: integration of the digital car sign in body design for new developments by the car manufacturer, new design options through flush integration into the body shell, thereby theft-proof, position, format, shape and size of the plate can vary with new developments
• - License plate recognizable in the dark, digital car display shines continuously day and night, low power consumption and / or without electricity due to bistable display status by means of electronic ink, better recognition and readability of the license plate, more information and additional information can be read
• - The license plate lighting at the rear of the car is not required
• - Display is compatible and can be retrofitted for conventional license plate mounts,
• -Avoidance of metal signs, which are changed up to 5 × on average in the life cycle
• - Digital vehicle sign is forgery-proof thanks to the double GPS function, ie GPS on-board computer and GPS of the digital number plate. When the vehicle number plate is removed, different GPS location is recognized and automatically reported to STVA and automatic notification to the police
• - Person recognition via sensor / camera
• -Anti-theft protection function: Vehicle access and driving function only possible by logging in the driver or access only by a defined driver- Group of people coding whether the vehicle was opened externally, GPS location of stolen vehicles
• - Acoustic and optical signals in case of attempted theft, automatic camera activation and automatic image transmission in the event of tampering with the vehicle sign, reporting to the police
• - Traffic control through built-in GPS detection, current information on board navigation, automatic navigation control, traffic management system, traffic jam minimization
• - Parking guidance system, car park occupancy, networking with car sharing offers Networking with car sharing offers

• -Einhaltung der Werte Pkw-Verbrauchskennzeichnungsverordnung
• -Kontrolle Treibstoffverbrauch über Bordcomputer Einhaltung des Energieverbrauchs Klasse a+- G
• -Kontrolle Lärm über Bordcomputer
• -Kontrolle Schadstoffemission über Bordcomputer

Control of vehicle manufacturers is an important new area of application. The diesel scandal has shown that state regulation and control of the overpowering / criminal auto industry will be required in the future. New laws could oblige automobile manufacturers to store compliance with laws and standards, such as environmental regulations, pollutant emissions and consumption values, in a measurable manner in the on-board computer. Here, the invention can help ensure that the state, the road traffic authority and the road traffic office control compliance with all requirements via the digital vehicle sign in conjunction with the on-board computer. An example of the new control options follows.

• - Compliance with the values of the passenger car consumption labeling regulation
• -Control of fuel consumption via on-board computer compliance with energy consumption class a + - G
• - Control noise via on-board computer
• -Control of pollutant emissions via on-board computer

Problem

The proliferation of the Internet, which began as Arpanet on October 29, 1969, has led to extensive global upheavals in many areas of life. It contributed to a modernization push in many Economic sectors and the emergence of new economic sectors and has led to a fundamental change in global communication behavior and media use in the professional and private spheres. For many experts, the Internet is considered to be one of the greatest global changes in information technology since the invention of book printing with a major impact on everyday life. In 2013, the Federal Court of Justice declared that the Internet is part of the livelihood of private individuals.

The internet is often called a legal space in political contexts, because national laws are viewed as difficult to enforce due to the international structure of the internet and anonymity. For a long time, government agencies had little knowledge of the function of the Internet and little experience in applying the law. Laws have been adjusted and case law has removed a number of uncertainties, at least de jure.

The increasing influence of the state is partly welcomed as an increase in legal certainty, partly criticized as progress towards a surveillance state, for example by the law on data retention that came into force on January 1, 2008 and which the Federal Constitutional Court classified as unconstitutional on March 3, 2010 has been. Internationally, the state's control of the Internet is also closely monitored, for example with the Internet in the People's Republic of China.

It is precisely in the use of fast, uncomplicated data transfer and the fulfillment of important organizational and structural tasks that there is also the risk of the Internet. Because power always brings with it abuse and so cyber crime has become a massive threat to the state and constitutional law and its citizens.

Cybercrime (Cybercrime) is a worldwide, growing, unsolved problem that does not stop at national borders or in front of closed doors. It can take place wherever people use computers, smartphones and other IT devices - in companies, authorities, universities, at home and on the go. The peculiarity of cyber crime is that the perpetrators can operate from almost anywhere and can hide their traces relatively well. In addition, the crime scene does not necessarily have to be the same as the scene of the crime. Not only the number of affected computers and smartphones increases, but also the professionalism of the perpetrators. There are more and more very well prepared cyber attacks on selected targets, where the damage potential for those affected is considerable. This includes, for example, attacks on commercial companies or critical infrastructure facilities.

In the narrower sense, according to the Federal Criminal Police Office, the following actions are referred to as cybercrime: spying, interception of data including preparatory actions, computer fraud, fraud with access rights to communication services, computer sabotage, data modification, falsification of evidence-relevant data, deception in legal transactions in data processing (§ 270),

In Germany, computer crime in the broader sense includes all crimes where IT is used for planning, preparation or execution. These now extend to almost all areas of crime in which the internet is used. For example: All forms of digital extortion, copyright and trademark infringement, unauthorized gambling, the distribution of prohibited substances, violations of the distribution ban or the protection of minors in the media, the exchange of child pornography, the online-based initiation of sexual abuse of children - the so-called cyber- Grooming or violence glorifying propaganda (sedition) or the violation of the very personal life through pictures, cyber-bullying. to cyber terrorism, cyber espionage, cyber bullying.

The transition to cyberwar methods and procedures (“net war”) has become fluid; in individual cases it is by no means easy to determine whether an attack on the Internet serves relevant criminal purposes or is intended for military or political reasons, for example in the event of a widespread sabotage of the highly ITC-dependent financial system or the websites of public institutions in the broadest sense. According to the observations, the “malware industry” is becoming increasingly professional, and attacks on computers and computer networks are becoming increasingly sophisticated.

Due to the flow of innovation in technology, the opportunities for profitable release of criminal energy are also increasing. To advertising terror - nuisance caused by adware that integrates and tries in the browser as a toolbar or add-on, e.g. Internet users have long been used to integrating advertising. Data collection by data monopolies such as Google, Facebook, Microsoft is also tolerated by the citizen and the state.

Platforms such as the so-called Darknet are a breeding ground for criminal networks. Such dark parallel universes, which are not easily accessible from the outside, can be used to plan and carry out actions that are part of cybercrime. An example of this is the exchange and distribution of child pornography content and the purchase of weapons or drugs.

But even outside of such networks, cybercriminals play their evil game, for example through “phishing” emails that serve to receive sensitive personal data. In particular, the infection and manipulation of computer systems by viruses and malware, such as Spyware, for storing sensitive user data or harmful virus codes that make programs and computers unusable. is a common practice. Personal data and access rights are recorded using Trojans, also known as malware, or other programs. This can steal the identity of the person concerned, which enables the perpetrator to hack bank accounts, for example, or to access social media platforms such as Facebook or Twitter. Kyptotrojaners (ransomware) are also used to enrich themselves financially. Such malware is used to block the infected devices. The re-release then takes place only after the payment of a requested ransom. Here, for example, there may be blackmail. Botnets are also tricky, i.e. several infected devices that the attacker can control remotely.

IT experts assume that online security, internet security, and IT security, i.e. protection against cybercrime is neither feasible nor manageable in the long run. On the contrary: Internet crime is expected to increase.

Therefore, there is an urgent need for action to ensure the information security of information processing and storage (technical or non-technical) systems, with the protection goals: confidentiality, availability and integrity. Protection from dangers or threats, and the avoidance of economic damage and the minimization of risks from cyber crime is a top priority for the state.

The goal of the state must be to guarantee the right to informational self-determination effectively and permanently, through innovative data protection procedures and systems that are legally anchored as data protection law. This requires radical changes in data protection law.

Data protection must be understood as protection against improper data processing and protection of the right to informational self-determination, protection of personal rights in data processing and also protection of privacy. Data protection is the right that everyone is basically free to decide who should have access to which of their personal data and when. (Data sovereignty) The essence of such data protection law is that the power inequality between organizations and individuals will be put under conditions. Data protection must counteract the tendency towards so-called transparent people in the increasingly digital and networked information society, the escalation of state surveillance measures (surveillance state) and the emergence of data monopolies by private companies

In Germany's right, the right to informational self-determination is the right of the individual to determine, in principle, himself about the disclosure and use of his personal data. According to the case law of the Federal Constitutional Court, it is a basic data protection right that is not expressly mentioned in the Basic Law for the Federal Republic of Germany. The proposal to insert a basic data protection right into the Basic Law has so far not found the required majority. However, personal data are protected according to the General Data Protection Regulation and Art. 8 of the EU Charter of Fundamental Rights.

However, since no country can solve this cross-border problem on its own, good international cooperation is essential.

5 : Omnicard and blockchain cloud according to the invention The following explanations apply to the 5 :

Object of the invention

The object of the invention is to solve all and any of the computer / internet and IT security problems described above by a technical, innovative digital IT system structure consisting of an arrangement of hardware and software components, and a method associated therewith Application of this hardware and software components. In particular, it is an object of the invention to provide encryption of the new IT system structure which offers 100% data security and does not allow misuse by cybercrime.

Description of the invention

The invention proposes a new IT system structure, based on the fact that initially a self-sufficient, central new IT system structure is provided in the form of a cloud, i.e. a computer network with online-based storage and server services for cloud computing with the aim of founding and operating an alternative internet to the worldwide web.

Cloud computing (German computer cloud or data cloud) describes the provision of IT infrastructure such as storage space, computing power or application software as a service over the Internet.

To put it more technically, cloud computing describes the approach of making IT infrastructures available via a computer network without having to install them on the local computer.

These services are offered and used exclusively through technical interfaces and protocols, for example using a web browser. The range of services offered as part of cloud computing encompasses the entire spectrum of information technology and includes, among other things, infrastructure, platforms and software.

The concept is to establish a central, state-controlled cloud, hereinafter referred to as "Eurodata", in the form of a computer network, with the function of an Internet or intranet initially operated at European level (EU countries) as a closed one , IT system structure for Europe, decoupled from the World Wide Web, with the option that in the future more - until all countries worldwide can be included. The aim is to replace the World Wide Web in the future and replace it with the secure "Eurodata" network, which then develops into the "Worldata" network.

The cloud "Eurodata" will in future be used to securely store, control and manage all data and information and transactions of every single citizen generated in Europe, based on the principle of informational self-determination, i.e. each individual person / citizen basically decides who, when and which of their personal data should be accessible. The sovereignty of data lies with the citizen. The data is stored secretly and is controlled and administered exclusively by each EU citizen. The citizen decides on the sharing of data with third parties and access permissions, which he defines and permits in his user profile. There are also strictly regulated access permissions to defined basic data of the individual citizen, e.g. for state, official e.g. Tax office, police etc. control purposes. After death, the data is deleted forever. Examples of data and transactions: Personal data: telephone number, mobile number, ID card, driver's license, bank credit cards, insurance data, health insurance, doctor's visits, contracts, tax data, income, investment income, kindergarten, school, job, training, employer, certificates, diploma, Self-employed, employment office, business transactions contracts, payment on the Internet and in retail, storage of private data, e.g. Photos, private documents, contracts and much more The advantage is a simplification of life for each individual citizen and the state bureaucracy. All relevant, personal 100% secured, securely stored. And always accessible.

After transferring all previous data to the Eurodata Cloud, every company (data monopolies such as Google, Facebook, Microsoft etc.) is legally obliged to delete all personal data. The concept is to set all data saved in the past to zero.

The same principle also applies to all, state, public and private / commercial / commercial information and data traffic, as well as for data storage that will be recorded and processed in the future via the "Eurodata" cloud. The aim is to centralize all information and to control it securely, in terms of information, through the "Eurodata" cloud.

The security of the "Eurodata" cloud is guaranteed by the blockchain process, a decentralized accounting system, unchangeable, tamper-proof and tamper-proof.

The blockchain process, a cryptographic chaining in a decentralized accounting system, is known as the technical basis for cryptocurrencies (Bitcoin), but can also help to improve or simplify transaction security in distributed systems compared to central systems. A blockchain is a chained sequence of data blocks that is updated over time, with each block typically containing a cryptographically secure hash (scatter value) of the previous block, a time stamp, and transaction data.

A blockchain is not stored centrally, but is kept as a distributed register. All participants save their own copy and continue to update it. It must be ensured that an identical chain is created for everyone involved. For this, suggestions for new blocks must first be worked out. This is done by validators (called “miners” in Bitcoin). Then the participants have to agree on which proposed block will actually be added to the chain. This is done through a so-called consensus protocol, an algorithmic procedure for voting. Cryptographic procedures ensure that the blockchain cannot be changed afterwards. The chain of blocks is therefore immutable, tamper-proof and tamper-proof.

The data stored on the blockchain can be viewed by everyone involved. However, they are not necessarily meaningfully legible for everyone, because content can be saved in encrypted form. Blockchains allow a flexible configuration of the level of confidentiality. By using digital signatures, information can be stored in the blockchain that can be tamper-proof that participants have undeniably stored certain data, such as initiating transactions.

The blockchain is also used when a bookkeeping system is managed decentrally and the correct state must be documented because many participants are involved in the bookkeeping. This concept is referred to as distributed ledger technology (decentralized account technology) or DLT. What should be documented is irrelevant to the term blockchain. It is crucial that later transactions build on previous transactions and confirm these as correct by proving knowledge of the previous transactions. This makes it impossible to manipulate or redeem the existence or content of previous transactions without also destroying all later transactions. Other participants in decentralized accounting who still have knowledge of the subsequent transactions would recognize a manipulated copy of the blockchain by the fact that it has inconsistencies in the calculations.

The decentralized consensus mechanism replaces the need for a trusted third party to confirm transaction integrity.

• • unveränderbare, fälschungs- und manipulationssichere Daten
• • aus Bürgersicht:
• • Abschaffung der Cyber- und Wirtschaftskriminalität, Betrug, Steuerhinterziehung,... etc. ,
• • Wertvolle Informationsdaten für gemeinnützige, gesellschaftliche und kulturelle Zwecke in den Bereichen Gesundheit, Medizin, Umwelt etc.
• • Transparenz sämtlicher Prozesse der Wirtschafts.- und Finanzwelt durch staatliche Kontrollmöglichkeiten mit „Eurodata“
• • Schutz großer Datenmengen mittels Verschlüsselung und Zugriffsverwaltung;
• • Möglichkeit, große Datenmengen unternehmensübergreifend zu sammeln und analysieren;
• • einfachere Verifzierung von Datenbezugspunkten;
• • automatische Aufspüren von Schwachstellen in der Lieferkette, im Zahlungsverkehr und anderen Geschäftsprozessen;
• • Reduktion oder Vermeidung von unnötigen Kosten für die IT-Infrastrukur;
• • Reduktion der Kosten für interne und externe Finanztransaktionen, Finanzreporting und Verwaltung;
• • Schaffung eines Mechanismus zur Verbesserung des Vorstandsreportings und des regulatorischen Reportings;
• • Beschleunigung des Jahresabschlusses.

The decentralization of IT through the Eurodata "Cloud" in general and blockchain in particular brings considerable advantages for all, private, state, public and economic / commercial information and data traffic:

• • unchangeable, tamper-proof and tamper-proof data
• • from a citizen's perspective:
• • Abolition of cyber and economic crime, fraud, tax evasion, ... etc.,
• • Valuable information data for non-profit, social and cultural purposes in the areas of health, medicine, environment etc.
• • Transparency of all processes in the economic and financial world through state control options with "Eurodata"
• • Protection of large amounts of data using encryption and access management;
• • Ability to collect and analyze large amounts of data across companies;
• • easier verification of data reference points;
• • automatic detection of weaknesses in the supply chain, in payment transactions and other business processes;
• • Reduction or avoidance of unnecessary IT infrastructure costs;
• • Reduction of costs for internal and external financial transactions, financial reporting and administration;
• • Creation of a mechanism to improve board reporting and regulatory reporting;
• • Accelerate annual accounts.

This radical step of the "Eurodata" cloud implementation based on the blockchain process is necessary and without alternative in order to finally end the previously unmanageable and unresolvable security problems of the Internet (World Wide Web). This requires a fundamental, new European legal regulation and legislation in the area of information and data security, which obligates every citizen and every company / institution to participate in "Eurodata".

For the practical implementation of cloud computing with "Eurodata", it is necessary that every citizen / participant or each company / institution receives an access authorization by means of an encrypted, tamper-proof and tamper-proof procedure for identification and authentication.

The essence of the invention proposes the use of an electronic element with processor and memory function for use as a computer, smartphone, PDA, tablet, PC, server, game console, netbook, notebook, mainframe, supercomputer, Device element and / or component element with connection and / or identification and / or assignment and / or authentication function user in the network, in particular radio network, characterized in that the electronic element is a digital link with at least one hardware element and / or a ( integrated) software, preferably for image recognition, in particular iris recognition.

The invention provides for the Irisscan to be used as a detection method, as access authorization to the “Eurodata” cloud. The Irisscan is a scientifically recognized, safe method of identifying a person. Iris detection is a method of biometrics for the purpose of authenticating or identifying people. For this purpose, images of the iris (iris) of the eye are recorded with algorithms, the characteristic features of the respective iris are identified using algorithmic methods, converted into a set of numerical values (feature vector, “template”) and used for recognition by a classification algorithm such as . B. stored a neural network or compared with one or more templates already stored. Commercial detection methods record around 260 individual optical features of the iris. For this it is necessary that every citizen is legally obliged to participate in an official Irisscan, e.g. the right eye, which is then stored as data and / or image data in the "Eurodata" cloud for the identification of each individual citizen.

As a further security level for access authorization to the "Eurodata" cloud, the invention proposes a secure encryption method in which an identity code is generated for each individual citizen using software that is digitally linked to the Irisscan in the "Eurodata Cloud". The identity code is generated anonymously by the software and is kept strictly secret for everyone and is assigned to the official Irisscan of each individual / citizen as a link and is only stored in the Eurodata Cloud. The security concept provides that every person / citizen is given this identity code by birth is assigned once by the state as a lifelong identity code, which also acts as a password, for all matters of life / digital life from AZ (identification function, online purchases, doctor, insurance ... etc.) as the only lifelong password that is only valid is linked to the current iris recognition and iris identification of each individual citizen.

The invention provides that at least one encryption code is used for identification. It is further provided that the encryption code consists of at least eight characters, based on a character space of at least 89 characters.

Mathematically, this means that there are 89 to 8 ways of creating a code / password, which results in infinite in the mathematical result. Such a code is 100% secure because it cannot be decrypted because the computing time, for example with a brute-force attack by a hacker, is infinitely long.

As a result, the identity code / password is stored anonymously and absolutely secret in the Eurodata Cloud and is not known to anyone, not even the individual citizen.

Advantage: The previous password chaos due to new, changed and forgotten passwords on the Internet is completely eliminated and the password does not have to be written down or memorized since it is only valid in connection with a current Irisscan.

Furthermore, the invention provides a method with which the access authorization to the "Eurodata" cloud of every individual citizen can be exercised securely. Every citizen can use it to store data, pay on the Internet etc.

For this purpose, the state provides an electronic element, called an Omnicard, with processor and memory function configured for each individual citizen with the citizen's individual identification code. This electronic element is, for example, in a computer, e.g. Smartphone installed. The electronic element (Omnicard) has the function of a SIM card that automatically connects to the Eurodata Cloud via the citizen's iris scan and unlocks access or a transaction when the citizen is recognized. For this it is necessary that in future there will only be a single, state-controlled cable and radio network and also the production and installation of the electronic element (Omnicard) in e.g. Computer, smartphone, PDA, tablet, PC, server, game console, netbook, notebook, mainframe, monitors, displays or / and in other device and / or component elements are placed under state control , for example by state-certified companies.

The invention further provides that the iris recognition takes place via a hardware element, preferably by a camera and / or a scanner, which is integrated into the electronic element and / or is connected to it. It is also provided that the electronic element is equipped with and / or is connected to a preconfigured state software which has at least one program for image recognition, in particular iris recognition.

As identification, for example for paying in the supermarket, the citizen uses his smartphone to create an Irisscan, preferably the right eye, using the Omnicard software / app and the camera, which automatically creates a connection to the "Eurodata" cloud, where the current Irisscan, e.g. is compared with the officially stored Irisscan by means of image recognition software, and is linked to the identification code and, upon detection, the payment is activated. So that such transactions are absolutely secure, the omnicard software creates a current time stamp of the iris scan, which is only valid for a limited time, e.g. 9 minutes. This prevents abuse by e.g. excluded by hacker attacks with fake iris scans, since only camera recording via the Omnicard software and camera with time stamp is accepted.

1. 1. Scanner, Camera Software für Iris-identifizierung
2. 2. Geschäftliche Transaktionen und Einkäufe, Bezahlen im Internet und Einzelhandel
3. 3. Speicher und Verwaltungsprogramm für alle digitalen Angelegenheiten des Bürgers
4. 4. Einstellungen des Nutzerprofils, (z.B.Teilen von Daten mit Dritten)
5. 5. Kommunikationssoftware, Email, Eurotalk (wie whatsapp)
6. 6. Gemeinschaftsdatenbank mit Zugriff für Bürger, Steuern und Abgaben - Gesundheit ,Umwelt und Ökologie , Sicherheit, Presse etc.

The invention proposes that the Omnicard software / app have other programs in addition to the iris recognition. The Omnicard app contains the following functions, for example:

1. 1. Scanner, camera software for iris identification
2. 2. Business transactions and purchases, payment on the Internet and retail
3. 3. Storage and administration program for all digital matters of the citizen
4. 4. User profile settings (e.g. sharing data with third parties)
5. 5. Communication software, email, Eurotalk (like whatsapp)
6. 6. Community database with access for citizens, taxes and duties - health, environment and ecology, security, press etc.

The same principle also applies to all, state, public and economic / commercial information and data traffic, as well as for data storage that will be recorded and processed in the future via the "Eurodata" cloud. Every company operating in Europe is legally obliged to participate in the Eurodata Cloud. Those who do not participate have no business authorization and are excluded from themselves. To clearly assign responsibilities, all transactions in this area are carried out exclusively via the identity code of each individual citizen linked to his or her function, e.g. as an employee of a company, in the state / public service, e.g. State government, police, authorities e.g. Tax office, politicians ... etc. Here, the invention proposes to provide a database structure with access rights for the different user groups. In particular, the taxation of Internet companies such as Google, Facebook, Microsoft etc. can thus be regulated and controlled by law.

In other words, the invention proposes as a technical core or contribution the use of an electronic element with processor and memory function for use as a computer, smartphone, PDA, tablet, PC, server, game console, netbook, Notebook, mainframe, supercomputer, monitor, display, device and / or component element with connection and / or identification and / or Assignment and / or authentication function of a user in the network, in particular radio network, characterized in that the electronic element has a digital link with at least one hardware element and / or (integrated) software, preferably for image recognition, in particular iris recognition.

In my opinion, the Omnicard can be implemented in Europe in 2025.

Further embodiments and definition of terms for the invention

computer

A computer [kɔm’pju: tɐ] or computer (outdated electronic data processing system) is a device that processes data using programmable calculation rules.

Charles Babbage and Ada Lovelace are considered to be the pioneers of the modern, universally programmable computer thanks to the analytical engine designed by Babbage in 1837. Konrad Zuse (Z3, 1941 and Z4, 1945), John Presper Eckert and John William Mauchly (ENIAC, 1946) built the first functional devices of this kind. Turing completeness plays an important role in classifying a device as a universally programmable computer. It is named after the English mathematician Alan Turing, who introduced the logical model of the Turing machine in 1936. ^{[1] [2]}

The early computers were also called (main) computers; their input and output of the data was initially limited to numbers. Modern computers understand how to deal with other data, such as letters and sounds. However, this data is converted into numbers within the computer and processed as such, which is why a computer is still a computing machine today.

With increasing performance new areas of application opened up. Computers can be found in all areas of everyday life today, mostly in specialized variants that are tailored to a given application. Integrated mini computers (embedded system) are used to control everyday devices such as washing machines and video recorders or for coin checking in vending machines; In modern automobiles, for example, they are used to display driving data and control various maneuvers themselves in "driving assistants".

Universal computers can be found in smartphones and game consoles. Personal computers (as opposed to many mainframes used) are used for information processing in business and government, as well as among private individuals; Supercomputers are used to simulate complex processes, e.g. B. in climate research or for medical calculations.

Basically, there are two types of construction: A computer is a digital computer if it processes digital data with digital device units (i.e. numbers and text characters); it is an analog computer if it processes analog data with analog device units (i.e. continuously running electrical measurements such as voltage or current).

Today digital computers are used almost exclusively. These follow common basic principles with which their free programming is made possible. A basic distinction is made between two basic components of a digital computer: the hardware, which is formed from the electronic, physically tangible parts of the computer, and the software, which describes the programming of the computer.

A digital computer initially only consists of hardware. First of all, the hardware provides a memory in which data can be saved in portions as on the numbered pages of a book and called up at any time for processing or output. Second, the arithmetic unit of the hardware has basic modules for free programming, with which any processing logic for data can be represented: These modules are in principle the calculation, the comparison and the conditional jump. A digital computer can, for example, add two numbers, compare the result with a third number and then continue depending on the result either at one or the other point in the program. In computer science, this model is theoretically represented by the Turing machine mentioned at the beginning; the Turing machine represents the fundamental considerations of predictability.

However, the digital computer only becomes useful if software is used. In principle, every software is a defined, functional arrangement of the calculation, comparison and conditional blocks described above Jump, whereby the blocks can be used as often as you like. This arrangement of the modules, which is referred to as a program, is stored in the form of data in the memory of the computer. From there it can be read out and processed by the hardware. This principle of operation of digital computers has not changed significantly since its origins in the middle of the 20th century, although the details of the technology have been significantly improved.

Analog computers work on a different principle. Analog components (amplifiers, capacitors) replace logic programming. In the past, analog computers were used more often to simulate control processes (see: Control technology), but today they have been almost completely replaced by digital computers. In a transition period, there were also hybrid computers that combined an analog computer with a digital computer.

• • Mediengestaltung (Bild- und Textverarbeitung)
• • Verwaltungs- und Archivierungsanwendungen
• • Steuerung von Maschinen und Abläufen (Drucker, Produktion in der Industrie durch z. B. Roboter, eingebettete Systeme)
• • Berechnungen und Simulationen (z. B. BOINC)
• • Medienwiedergabe (Internet, Fernsehen, Videos, Unterhaltungsanwendungen wie Computerspiele, Lernsoftware)
• • Kommunikation (Chat, E-Mail, soziale Netzwerke)
• • Softwareentwicklung

Possible uses for computers are:

• • Media design (image and text processing)
• • Administration and archiving applications
• • Control of machines and processes (printers, production in industry by e.g. robots, embedded systems)
• • Calculations and simulations (e.g. BOINC)
• • Media playback (internet, television, videos, entertainment applications such as computer games, educational software)
• • Communication (chat, email, social networks)
• • software development

Hardware architecture

• • das Rechenwerk (im Wesentlichen die arithmetisch-logische Einheit (ALU)),
• • das Steuerwerk,
• • die Buseinheit,
• • das Speicherwerk sowie
• • die Eingabe-/Ausgabewerk(e).

The principle that is generally applied today, which John von Neumann described in 1946 as Von Neumann architecture, defines five main components for a computer:

• The arithmetic unit (essentially the arithmetic-logic unit (ALU)),
• • the control unit,
• • the bus unit,
• • the storage unit as well
• • the input / output plant (s).

In today's computers, the ALU and the control unit are usually merged into one component, the so-called CPU (Central Processing Unit, central processor).

The memory is a number of numbered, addressable "cells"; each of them can hold a single piece of information. This information is stored in the memory cell as a binary number, ie a sequence of yes / no information in the sense of ones and zeros.

With regard to the storage unit, an essential design decision of the Von Neumann architecture is that the program and data share a storage area (the data usually occupy the lower and the programs the upper storage area). In contrast, in Harvard architecture, data and programs have their own (physically separate) memory areas. Access to the memory areas can be realized in parallel, which leads to speed advantages. For this reason, digital signal processors are often implemented in Harvard architecture. Furthermore, data write operations in the Harvard architecture cannot overwrite programs (information security).

In the Von Neumann architecture, the control unit is responsible for memory management in the form of read and write access.

The ALU has the task of combining values from memory cells. It receives the values from the control unit, calculates them (adds two numbers, for example) and gives the value to the Control unit back, which can then use the value for a comparison or write to another memory cell.

Finally, the input / output units are responsible for entering the initial programs into the memory cells and displaying the results of the calculation to the user.

Software architecture

To a certain extent, the Von Neumann architecture is the lowest level of the functional principle of a computer above the electrophysical processes in the conductor tracks. The first computers were actually programmed in such a way that the numbers of commands and of certain memory cells were written one after the other into the individual memory cells as required by the program. Programming languages were developed to reduce this effort. These automatically generate the numbers within the memory cells, which the computer ultimately processes as a program, from text commands that also represent semantically understandable content for the programmer (eg GOTO for the "unconditional jump").

Later, certain repetitive procedures were grouped together in so-called libraries in order not to have to reinvent the wheel every time. For example: interpreting a pressed keyboard key as letter "A" and thus as number "65" (in ASCII code). The libraries were bundled into superordinate libraries, which link sub-functions to complex operations (example: the display of a letter "A", consisting of 20 individual black and 50 individual white dots on the screen after the user has pressed the "A" key) .

In a modern computer, many of these program levels work above or below one another. More complex tasks are broken down into subtasks that other programmers have already worked on, which in turn build on the preparatory work of other programmers whose libraries they use. At the lowest level there is always the so-called machine code - the sequence of numbers with which the computer is actually controlled.

species

• • Analogrechner
• • Digitalrechner
• • Hybridrechner

Based on how the computer works

• • Analog computer
• • digital computer
• • Hybrid computer

• • Smartphone
• • Personal Digital Assistant oder PDA, waren die Vorläufer der Smartphones.
• • Tabletcomputer
• • Micro computer (veraltet)
• • Eingebettetes System, z. B. im Auto, Fernseher, Waschmaschine usw.
• • Einplatinencomputer, z. B. Raspberry Pi, billigste, sehr kleine Computer. Werden meist als eingebettete System verwendet.
• • Personal computer oder PC, hier als Desktop-Computer oder auch Arbeitsplatzrechner verstanden.
• • Hostrechner oder auch Server, eingebunden in einem Rechnernetz, meist ohne eigenen Display, Tastatur usw.
• • Thin Client sind Rechner, die nur in Zusammenarbeit mit einem größeren Rechner, meist server, richtig funktionieren.
• • Heimcomputer (veraltet), der Vorläufer des PC.
• • Spielkonsole
• • Netbook, ein kleines Notebook.
• • Laptop oder Notebook
• • Mini Computer (veraltet)
• • Superminicomputer (veraltet)
• • Mikrocomputer (veraltet)
• • Mainframe computer oder Großrechner.
• • Super computer, die schnellsten Rechner ihrer Zeit, brauchen den Platz einer Turnhalle, die Energie einer Kleinstadt und sind sehr teuer.

Based on the size

• • smartphone
• • Personal Digital Assistant, or PDA, were the forerunners of smartphones.
• • tablet computer
• • Micro computer (out of date)
• • Embedded system, e.g. B. in the car, television, washing machine etc.
• • Single board computer, e.g. B. Raspberry Pi, cheapest, very small computer. Are mostly used as an embedded system.
• • Personal computer or PC, here understood as a desktop computer or workplace computer.
• • Host computer or server, integrated in a computer network, usually without its own display, keyboard, etc.
• • Thin clients are computers that only work properly in cooperation with a larger computer, usually a server.
• • Home computer (out of date), the forerunner of the PC.
• • Game console
• • Netbook, a small notebook.
• • Laptop or notebook
• • Mini computer (out of date)
• • Super Mini Computer (out of date)
• • microcomputer (obsolete)
• • Mainframe computer or mainframe.
• • Super computers, the fastest computers of their time, need the space of a gym, the energy of a small town and are very expensive.

Future prospects

Future developments are likely to consist of the possible use of biological systems (biocomputers), further links between biological and technical information processing, optical signal processing and new physical models (quantum computers).

A major megatrend is currently (2017) the development of artificial intelligence. These simulate the processes in the human brain and create self-learning computers that are no longer programmed as before, but are trained with data similar to a brain. The point in time at which artificial intelligence exceeds human intelligence is called technological singularity. Artificial intelligence is already used (2017) in many applications, including everyday ones (see applications of artificial intelligence). Hans Moravec put the brain's computing power at 100 teraflops, Raymond Kurzweil at 10,000 teraflops. Supercomputers have already significantly exceeded this computing power. For comparison, a graphics card for 800 euros (5/2016) with a performance of 10 teraflops. ^[7] (see technological singularity)

For further developments and trends, many of which still have the character of keywords or hypes, see Autonomy Computing (= computer autonomy), Grid Computing, Cloud Computing, Pervasive Computing, ubiquitous Computing (= computer ubiquity) and Wearable Computing.

The worldwide web search for the term "computer" has been steadily decreasing since the start of statistics in 2004. In the 10 years to 2014, this number of hits had dropped to a third.

hardware

Hardware [/ 'ha: d wεɘ / or /' hard, wεɘ / (AE)] (sometimes abbreviated with "HW") is the generic term for the physical components (the electronic and mechanical components) of a data processing system, as a complement to Software (the programs and data). ^[1]

Word origin

Originally, the English hardware is roughly equivalent to "hardware" and is still used in this sense in the English-speaking world - not just for computer hardware.

Differentiation between hardware and software

Hardware and software components are used in a computer system. In simple terms, hardware is the part of a computer that you can touch: every single component built into it, from a simple capacitor to a fully populated circuit board, the device as a whole and its accessories such as a mouse, keyboard, screen and printer.

Software is information and cannot be touched because it is immaterial. ^[2] It can be divided into programs and data and determines what a computer does and how it does it (roughly comparable to a manuscript). ^[3] The hardware (the device itself) executes software (executes it) and puts it into practice.

In the 1950s, software was stored on paper tape. Each possible hole position stands for one bit. However, the holes are not the software; they are part of the hardware. Even modern data carriers are not software, but always hardware that only contains software.

Like information, software cannot exist without physical representation: software can be saved, printed, displayed or transported on certain media. However, these are not the software, they only contain them. As an analogy, it is not conceptual for an 'opera' whether it is performed in the theater, broadcast on radio / TV or sold or heard on CD, whether it is described in the opera guide or recorded in the score. Again, these media only contain the opera.

The hardware and software controlled working principle

You don't necessarily need software to automatically control hardware in your workflow. Even complex workflows can be completely implemented in hardware - the hardware-controlled working principle. One example is one of the early arcade games, the Breakout game produced by Atari in 1976.

The complete "program" (the process, the logic) consisted exclusively of hardware, figuratively speaking, of "hard-wired control panels". ^[4]

Even in modern devices, automated workflows are sometimes implemented directly in the hardware, in the form of logic gates. They implement a certain sequence of instructions. Their function is fixed by the structure of the hardware and can hardly be changed afterwards. To update to new functions or to correct errors, the hardware has to be replaced (at least partially), supplemented or adapted through other physical interventions. However, the processing speed is generally higher and the energy consumption is lower than with a software solution.

If a workflow should be adaptable without physical intervention, the software-controlled working principle comes into play: the hardware is given a processor for this. This is able to “understand” software, to process it. Software can in turn be easily adapted and even completely replaced without having to change the hardware for it. This means that almost any application can be used on the same device.

More complex hardware systems often contain a combination of hardware and software controlled components.

In the example above, the 1976 Atari game machine produced no processor. Just a year later, the game principle was transferred to a processor-controlled device, the computer. Since then, the game has also been available as software. ^[4] The computer game no longer consisted of "wired control panels", but instead of instructions for a processor including the additional information (data) necessary for processing, which were stored together on a data carrier and evaluated by the computer.

Subdivision

Motherboard

• • Steuerwerk zur ALU und zur Befehlskodierung gleich mehrere Male zur Parallelverarbeitung;
• • Steuerwerk MMU zur Speicherverwaltung;
• • der Cache als Teil des Speicherwerks,
• • die Steuerung für ein Bus-System, das interne und externe Komponenten miteinander verbindet.

A possible realization or division of the hardware is the Von Neumann architecture presented in 1945. It differentiates abstractly between control unit, arithmetic unit ("ALU"), storage unit and input / output unit (peripheral device). Nowadays, such a division is still useful and necessary for understanding the structure of a computer, although many functions are now integrated in a hardware chip in modern processors, for example:

• • Control unit for ALU and for command coding several times for parallel processing;
• • MMU control unit for memory management;
• The cache as part of the storage system,
• • the controller for a bus system that connects internal and external components.

In so-called embedded processors (for e.g. PDAs or washing machines), an input / output mechanism in the form of serial interfaces (e.g. USB), digital I / O (input / output) e.g. B. for a touchscreen and analog I / O for z. B. lamps or electric motors.

So-called SoC (System on a Chip) for z. B. Smartphones, which integrate other components, up to working memory (RAM) and flash memory.

• • Die Grundbestandteile der Rechnerarchitektur: Hauptplatine (auch Motherboard oder Mainboard genannt) mit Chipsatz (für IO), Prozessor und Arbeitsspeicher (RAM)
• • Massenspeicher: Laufwerke (Festplattenlaufwerk, Flash-Speicher, CD-ROM-Laufwerk, DVD-Laufwerk, Zip-Laufwerk, Jaz-Laufwerk, ...) und Speichermedien
• • Erweiterungskarten (Grafikkarte, Soundkarte, Netzwerkkarte, TV-Karte, ISDN-Karte, USB-Karte, PhysX-Karte, ...)
• • Netzteil, Gehäuse, Lüfter
• • Peripheriegeräte:
  • ◯ Ausgabegeräte (Drucker, Bildschirm, Beamer, Lautsprecher, ...)
  • ◯ Eingabegeräte (Tastatur, Maus, Joystick, ...)
  • ◯ Einlesegeräte (Mikrofone, Kartenlesegeräte, verschiedene Arten von Scannern, ...)

The computer components include the PC components:

• • The basic components of the computer architecture: main board (also called motherboard or mainboard) with chipset (for IO), processor and RAM (RAM)
• • Mass storage: drives (hard disk drive, flash memory, CD-ROM drive, DVD drive, Zip drive, Jaz drive, ...) and storage media
• • Expansion cards (graphics card, sound card, network card, TV card, ISDN card, USB card, PhysX card, ...)
• • Power supply, housing, fan
• • Peripherals:
  • ◯ Output devices (printer, monitor, projector, loudspeaker, ...)
  • ◯ Input devices (keyboard, mouse, joystick, ...)
  • ◯ Readers (microphones, card readers, various types of scanners, ...)

All of these peripheral devices and assemblies of a computer are largely constructed with logic circuits.

Hardware is often provided with an FCC number, which allows the manufacturer to be clearly identified.

screen

A screen (also monitor or English screen or display) is an electrically controlled display without moving parts for the optical signaling of changing information such as pictures or characters. The screen can be an independent device or part of a device.

Definition of terms

The terms screen, monitor, screen and display are often used synonymously in German; There are nevertheless linguistic differences for the latter two of English origin. The display of a screen is actually directly visible on the device. Monitors (compare monitoring for "monitoring") are therefore only called screens that are used as components and peripheral devices.

In contrast, the projection surface of a projector, such as the screen, is also referred to in English as a screen (roughly, screen '). On the other hand, in German all display devices in the broader sense are also called displays (roughly, display '), for example flip-dot displays.

history

Screens based on Braun tubes have been used as output devices since the 1930s, initially with vector control (see vector screen). The video terminals that emerged later mainly use raster graphics to build up the image. With most video terminals, the individual pixels cannot be addressed directly, rather a character generator (character processor) takes over the representation of individual characters; the number and the appearance of characters that can be represented are thus predetermined.

In the early 1980s, graphic output became more and more important, among other things, the development of CAD and graphical user interfaces (GUI, Graphical User Interface), which became popular with the Macintosh.

In 2003, according to a survey by the Society for Consumer and Communication Electronics (gfu), more liquid crystal screens were sold in Germany than conventional devices with picture tubes. The screen diagonals for typical desktop applications today are mostly between 50 and 75 cm, for notebooks about 34 to 43 cm are common.

Early personal computers, like computer terminals at the time, often had integrated screens. Today this is only common for portable computers such as notebooks and handhelds. Monitors for fixed use are usually installed in separate housings, which also contain the electronics for their control and are usually connected to a graphics card inserted into the computer via standardized interfaces such as VGA or DVI.

Since around 2001 there have also been screens that can display three-dimensional images, so-called autostereoscopic displays or 3D monitors. Development is still at an early stage, a perfectly worked out virtual reality is not yet possible with them.

A so-called smart display is a monitor that is connected to the computer by radio and is therefore portable to a limited extent.

properties

The screen diagonal is the size of the screen and always refers to the diagonal of the picture tube, which was slightly larger than the visible diagonal for picture tubes. Other characteristics of a monitor are the aspect ratio, the maximum line frequency, from which the refresh rate results for a certain image height, the maximum pixel clock (these three frequencies and the vertical and horizontal blanking interval result in the resolution), the brightness, the contrast, the response time and, in particular with liquid crystal screens, the number of pixels and the maximum viewing angle. In the case of tube monitors, the type (perforated, stripe or slit mask) and the grid of the mask are also relevant.

Multiple display

A multiple display, also a multifunctional display, serves to display multiple information. This can be a single electronic device or a composite system with multiple screens. The purpose of this is to be able to display a large number of required values or also pictures and signals at the same time with several display devices or in succession on the same display. For this, specified or currently processed data must be visualized and output.

Today, this is used in a large number of applications, for example in the electronic flight instrument display system in aircraft, in mobile telephones (cell phones), in tablet PCs or in digital television.

Well-known and widespread methods for simultaneous display is the window technology - which gave the Windows operating system its name - on the personal computer. Different programs can be arranged side by side in so-called “windows”, whereby one or more monitors can also be used here.

Representation techniques

• • Feldemissionsbildschirm („FED“)
• • Flüssigkristallbildschirm („LCD“)
• • Dünnschichttransistorbildschirm („TFT-LCD“)
• • Kathodenstrahlröhrenbildschirm („CRT“)
• • Plasmabildschirm
• • Organische Leuchtdiode („OLED“)
• • Surface-conduction Electron-emitter Display („SED“)
• • Kathodenstrahlröhre mit kontinuierlicher fluoreszierender Beschichtung (Oszilloskop)
• • Bildpunkt-Maskentypen (Pixeling)
• • Röhrenmonitor-Wiedergabe (Lochmaske)
• • Röhrenmonitor-Wiedergabe (Streifenmaske)
• • Röhrenmonitor-Wiedergabe (Bildausschnitt). Alle Farbpunkte liegen auf einer Linie, die von drei Elektronenstrahlen (je Farbe einer) zeilenweise zum Leuchten angeregt werden.
• • Matrix eines Fernsehbildschirmes

Representation techniques used are:

• • Field emission screen ("FED")
• • Liquid crystal display ("LCD")
• • Thin film transistor screen ("TFT-LCD")
• • CRT screen ("CRT")
• • Plasma screen
• • Organic light-emitting diode ("OLED")
• • Surface-conduction electron-emitter display ("SED")
• • cathode ray tube with continuous fluorescent coating (oscilloscope)
• • Pixel mask types
• • Tube monitor playback (shadow mask)
• • Tube monitor playback (stripe mask)
• • Tube monitor playback (image detail). All color dots lie on a line, which are excited by three electron beams (one per color) to line up.
• • Matrix of a television screen

application areas

• • Bedienelementen von Maschinen und Geräten aller Art
• • Anzeigegeräte in allen Bereichen der Technik
• • Fernsehgeräten
• • Computermonitoren
• • Radargeräten, Oszilloskopen
• • bildgebenden Verfahren in Wissenschaft
• • medizinischen Diagnose- und Überwachungsgeräten (Monitore)
• • Notebooks, PDAs (Handhelds, Organizer), Mobiltelefonen
• • Digitalkameras und Camcordern
• • elektronischen Navigationsgeräten
• • Werbeanzeigen, Informationsschildern im Straßenverkehr

They are used in

• • Control elements of machines and devices of all kinds
• • Display devices in all areas of technology
• • TV sets
• • computer monitors
• • radars, oscilloscopes
• • imaging methods in science
• • medical diagnostic and monitoring devices (monitors)
• • Notebooks, PDAs (handhelds, organizers), mobile phones
• • Digital cameras and camcorders
• • electronic navigation devices
• • Advertisements, information signs in road traffic

• • Bildschirmarbeitsverordnung
• • Bildschirmmedien
• • Breitbildmonitor
• • Display PostScript
• • Elektronisches Papier
• • Head-Mounted Display
• • Kontrastverhältnis
• • TCO (Standard)
• • Touchscreen

See also

• • VDU regulation
• • Screen media
• • Widescreen monitor
• • Display PostScript
• • Electronic paper
• • Head-mounted display
• • Contrast ratio
• • TCO (standard)
• • touchscreen

Advertisement (technology)

In technology, the display generally describes a device for optically signaling changeable information (states and values), in particular measured values. They differ from license plates, which offer constant information. In the work system, displays represent an interface between people and a technical process or the environment.

A display can have very different designs and be based on different technical implementations. A distinction is made between mechanical, electromechanical and electronic displays. According to the type and meaning of the display itself, it can also be divided into binary displays, scale displays, numerical displays and graphic displays. It differs in ergonomics DIN EN 8942-2 [1] between visual, acoustic and tactile displays.

Designs and technical implementations of advertisements

Mechanical indicators

Mechanical displays in turn distinguish between continuous and discrete displays.

• • Mechanische Tachometer setzen die Drehzahl einer Welle in einen dazu proportionalen Winkel eines Zeigers um.
• • Eine mit einem Zeiger kombinierte Aufwickeleinrichtung für einen Faden misst, wie tief ein an dem Faden hängender Schwimmer abgesunken ist, und zeigt damit den Füllstand an, u. a. an Öltanks.
• • Pegelstandanzeiger oder kurz Pegel, wie sie an vielen Flüssen zu finden sind, oder auch Wasser- bzw. Füllstandsanzeigen, z. B. an Kesseln oder Kaffeemaschinen, zeigen durch direkten Blick auf den Flüssigkeitsstand an einer Skale, oftmals über ein Schauglas, den Füllgrad bzw. den Wasserstand an.
• • Flüssigkeitsthermometer
• • Bimetallthermometer
• • analoge mechanische Waagen (Zeiger, bewegte oder projizierte Skale)
• • Abstimm-Skale zur Senderwahl an Radios

Examples of continuous mechanical displays:

• • Mechanical tachometers convert the speed of a shaft into a proportional angle of a pointer.
• • A winding device for a thread combined with a pointer measures how deep a float hanging on the thread has sunk, and thus indicates the fill level, including on oil tanks.
• • Level indicator or level for short, as can be found on many rivers, or water or level indicators, z. B. on kettles or coffee machines, show by looking directly at the liquid level on a scale, often through a sight glass, the degree of filling or the water level.
• • Liquid thermometer
• • Bimetal thermometer
• • analog mechanical scales (pointer, moving or projected scale)
• • Tuning scale for radio station selection

• • Eisenbahn-Formsignale in verschiedenen Bauformen für Anweisungen wie „Fahrt“ und „Halt“
• • Kennmelder an Schmelzsicherungen signalisieren einen durchgebrannten Schmelzleiter
• • mechanische Schrittzähler und Kilometerzähler; allgemein: Rollenzählwerke
• • Wasserzähler, Gaszähler

Example of discrete mechanical displays:

• • Railway shape signals in various designs for instructions such as "travel" and "stop"
• • Indicators on fuses signal a blown fuse
• • mechanical pedometer and odometer; general: roller counters
• • Water meter, gas meter

Electromechanical displays

• • Skalenanzeigen
  • ◯ mechanischer Zeiger
    • ■ Drehspulmesswerk
    • ■ Dreheisenmesswerk
  • ◯ Lichtzeiger
    • ■ Spiegelgalvanometer
  • ◯ sonstige
    • ■ Zungenfrequenzmesser
    • ■ elektrolytischer Betriebsstunden- oder Strommengenzähler
    • ■ Elektrometer

Continuous electromechanical displays:

• • Scale displays
  • ◯ mechanical pointer
    • ■ Moving coil measuring mechanism
    • ■ Moving iron measuring mechanism
  • ◯ light pointer
    • ■ Mirror galvanometer
  • ◯ other
    • ■ Tongue frequency meter
    • ■ Electrolytic operating hours or electricity meter
    • ■ electrometer

• • Elektromechanische Zähler mit Ziffernrollen
  • ◯ mit Ferrarismotor in Energiezählern
  • ◯ in Kilometerzählern
• • Fallblattanzeigetafeln an Flughäfen und Bahnhöfen für Texte und Uhrzeiten
• • Schauzeichen
• • Fallklappenrelais

Discrete electromechanical displays:

• • Electromechanical counters with digit rolls
  • ◯ with Ferrari motor in energy meters
  • ◯ in odometers
• • Leaflet bulletin boards at airports and train stations for texts and times
• • Indicators
• • Fall flap relay

Electrical and electronic displays

Electrically controlled displays without moving parts can be binary displays, numerical displays, but also analog displays (bar graph display, magic eye) or image displays. The term digital display usually means a digital display.

Technical implementation (examples):

• • Signal lamps [incandescent lamps or light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs)]
  • ◯ binary, color change, numerical display or bar graph
  • Vergleich Brightness comparison or flashing at different frequencies
• • liquid crystal displays (LCDs); Character, symbol, number or image display (smartphones, flat screens)
• • fluorescent displays (VFDs); Character or symbol display, also bar graph displays, magic eye
• • Braun tubes; y-x display for picture tubes, oscilloscopes, spectrum analyzers, measurement receivers, display in polar coordinates in radar devices
• • Nixie tubes (numerical display)

• • vektororientierte Ansteuerung
• • Raster- oder Matrixanzeige
• • Segmentanzeige (Sieben-Segment-Anzeige, Vierzehn-Segment-Anzeige, binäre Symboldarstellung)

Large-format LED matrix display on a Japanese traffic junction: he control types of complex electrical or electromechanical displays

• • Vector-oriented control
• • Grid or matrix display
• • Segment display (seven-segment display, fourteen-segment display, binary symbol display)

The screen (also monitor, display, smart display) is a very universal display instrument. As a Braun tube, it can be controlled in a vector and grid-oriented manner.

Liquid crystal screens are increasingly being used, which are controlled as matrices.

LC seven-segment displays, such as those found in digital measuring devices, wristwatches and radio clocks, are also widespread.

A virtual retinal display projects the information directly onto the retina of the eye.

Projection displays project alphanumeric characters or symbols onto a wall or screen. For alarm clocks with a projection display, a seven-segment display is projected, while u. a. In early mainframe computers, numerical displays were used that had 10 light bulbs, 10 collimator lenses, gobos 0 ... 9 and 10 appropriately aligned lenses for each digit so that each digit could be displayed in the same position on a focusing screen. In the past, complex devices such as the Eidophor system were required to project video images (video projector) onto large screens. For this purpose, projection techniques with LCDs or DLPs, called projectors in certain countries, have been available.

Head-up displays are reflected in a partially transparent plate (windshield, separate beam splitter disc).

Ads in measurement technology

In the DIN 1319-2, which is fundamental for measurement technology, a distinction is made between "scale display and numerical display" for "measuring devices with direct output".

Scale display using liquid crystal display

In the case of a measuring device with a scale display, a mark (e.g. a specific position of a physical pointer or a screen pointer, a light pointer (see e.g. mirror galvanometer), an edge, the meniscus of a liquid column) is usually set as a starting variable at a point on the scale or the scale is adjusted to it. For physical pointers see e.g. B. under analog multimeter, moving coil measuring mechanism.

Scale indicators can also be found on a large number of mechanical measuring devices such as scales and calipers; the latter use a vernier for more precise readability. Mirror scales also have one Mirror sector behind the pointer to facilitate vertical reading and thus to avoid a parallax error when reading.

Dial clocks, stopwatches and micrometers have 2 to 3 hands to increase the reading accuracy.

In the band display, either a variable number of segments is illuminated discontinuously or a variable length of the band is set continuously. It can be used for measurement or only for qualitative assessment, see bar graph display or magic eye. The discontinuous band display works digitally and combines digital technology with the advantages of a scale display.

Digital display

In the case of a measuring device in which the output variable is a numerical representation of the measured variable quantized in fixed steps, the number (sum) of quantization units or the number (sum) of pulses appear discontinuously in a sequence of digits. The number displays differ in the principles of number display. See section Electrical and electronic displays. Previous digit displays used ten discrete, backlit digits per digit, which were viewed or projected directly from the lighting.

The disadvantage of digital displays is that trends and the absolute size are not recognizable at first glance. For this reason, digital multimeters (DMM for short, i.e. those with a numerical display) sometimes also have a fast bar graph display or a pointer element, which, however, also consist of discrete display elements (see picture on the right).

Advantages are e.g. B. the representability of the measured value over wide areas by variable commas and additionally displayed units of measurement, the unambiguity of the reading as well as self-illuminating displays the good readability in poor lighting conditions.

additions

With appropriate output technology, additional ratings can be included in the advertisement; For example, a limit violation or danger in the system can be indicated by a flashing display, additional illuminated signs or changing colors.

Computer monitor

A computer monitor is a screen that is primarily intended for connection to a computer. Especially in the years between 1985 and 2005, televisions and computer monitors developed very far apart (quality, frame rates, signals, levels, plugs), since 2010 they have been growing together again.

In the early days of computers, there were no computer monitors and no computer keyboards and mice. Input and output took place via punched cards (stacks) or punched strips. This was created with punch card punches (or punch tape punches). Printers (actually teleprinters) ultimately provided the data that was stored on the punched cards or strips or rather was calculated from this data (list output).

From the beginning of the 1960s, mainframe systems such as the IBM S / 360 series came onto the market, which could be operated with the help of text commands via a keyboard, the output data being visualized on continuous paper with the help of a touch printer. Since only the binary control codes for the characters to be printed had to be transmitted for the printout, in contrast to the digital modulation of image data, this method could already be implemented before the invention of the monitor. The first computer terminals were designed in such a way that they could interpret the same control data as a printer at the time in order to generate text output on the screen.

Computer terminals

In the early 1970s, computer terminals began to appear. Typical representatives were e.g. B. the IBM 3270 terminals or VT100 terminals, of which ANSI.SYS under MSDOS still reminds. The detour via punched cards and tapes disappeared, with the help of such terminals one could communicate directly with a computer. A characteristic feature remained that the communication still had certain similarities with teletype and paper tape. Most of them, like teletypes, were controlled serially with text and control characters. Inputs were collected and transmitted to the central computer (with its precious computing time).

White, green or orange monochrome monitors were mostly used as monitors. The terminals usually had 80 or 132 characters per line with 24 or 43 lines. The resolution was between 240 and 350 lines, frame rates at 50 or 60 Hz, often with afterglow phosphor, to minimize flickering due to the image grid structure.

Emerging home computers, beginnings of the PC

• • Ansteuerung über einen HF-Modulator. Üblich sind maximal 40 Zeichen pro Zeile.
• • Ansteuerung mittels FBAS-Signal über einen Video-Eingang, der u. a. auch für Videorecorder gedacht war.
• • Ansteuerung mittels getrenntem Farb- und Helligkeitssignal (S-Video).
• • Ansteuerung mittels RGB-Signal (meist über SCART).

For home computers, they used existing technology - the home television. Special computer monitors were slightly better. The display quality also depends on the interface used between the computer and television; in ascending order:

• • Control via an RF modulator. A maximum of 40 characters per line are usual.
• • Control by CVBS signal via a video input, which was also intended for video recorders.
• • Control using separate color and brightness signals (S-Video).
• • Control via RGB signal (mostly via SCART).

The further down the list the procedure is, the less - the signal processing stages - which are actually only necessary for television transmission via antenna - are involved in the transmission; accordingly, there is no inherent limitation of signal quality due to bandwidth limitation or modulation artifacts. However, at the beginning of the home computer era, an input other than the one for the RF signal (antenna input) was not a matter of course on the existing television, which is why practically every television is suitable for output via the RF modulator. On the other hand, the image signal of many home computers is not based on an RGB signal at all; they generate a CVBS or S-Video signal directly, which is why an RGB monitor cannot be used there.

The emergence of high-resolution computer monitors

There were computer monitors for home computers such as the C64 as well as for office computers such as the IBM PCs. Over the following decades, the presentation standards for IT technology continued to develop, while due to the existing standards of television transmission there was practically no progress (apart from improvements in details). As a result, computer monitors and televisions developed extremely apart over almost 20 years. With the first step away from the television-compatible home computer, the display of a computer image on a television was practically impossible. However, the advances in digital technology made it relatively easy to change the standards in good quality. As a result, television signals can be generated from computer image data on the one hand, and on the other hand this was a prerequisite for the further development of television standards while maintaining downward and upward compatibility, which brings computer and television technology closer again.

Flat screens, digital interfaces

Around the year 2000, flat screens appeared in both the computer and television sectors. Plasma screens were initially used for televisions, and liquid crystal screens (LCD) with thin-film transistors (TFT) for computers. With DVI for computers and HDMI for TVs, very similar standards for driving displays have been developed.

connections

TV and home computer

In the field of home computers, the connection techniques for carrier frequency signals (via RF modulator), video and RGB signals (e.g. Belling-Lee connectors, BNC, Cinch, DIN or SCART connector).

Monitors

VGA plug and socket

• • Ära 1: Videosignale wurden genauso wie beim Fernsehgerät analog übertragen. Beliebig viele Farben konnten übertragen werden. Synchronisation wird mit dem Helligkeitskanal bzw. mit dem Grünkanal übertragen.
• • Ära 2: Der IBM-PC favorisierte die digitale Übertragung mit getrennter Übertragung der Synchronsignale.
  • ◯ Monochrom-Monitore wurden über zwei Signale angesteuert (Video, Intensity) und zwei Synchronsignale (HSync+ und VSync-)
  • ◯ Color Graphics Adapter-Monitore über vier Signale (Red, Green, Blue, Intensity) und zwei Synchronsignale (HSync+ und VSync-)
  • ◯ Enhanced Graphics Array-Monitore über sechs Signale (Red, Green, Blue, Red-Intensity, Green-Intensity, Blue-Intensity) und zwei Synchronsignale (HSync+ und VSync-)
• • Ära 3: Beim Video Graphics Array wurde von IBM pro Farbe (Rot, Grün, Blau) wieder nur eine Leitung verwendet, über die die Intensität analog übertragen wurde. Dabei wurden bis zu 2¹⁸ Farben unterstützt. Die beiden Synchronsignale blieben erhalten.
• • Ära 4: Digitale Übertragung von analogen Signalen als digitale Daten über 1 oder 2 Leitungen. Synchronsignale als spezielle Codeworte im digitalen Datenstrom.
• • Ära 5: In Ära 4 wird das Signal mit dem exakten Timing aus Ära 3 übertragen. Man löst sich auch von dieser Gewohnheit und überträgt Videodaten als asynchrone Pakete.

The transmission of video signals changed several times.

• • era 1 : Video signals were transmitted in the same way as on the television. Any number of colors could be transferred. Synchronization is transmitted with the brightness channel or with the green channel.
• • era 2nd : The IBM PC favored digital transmission with separate transmission of the synchronous signals.
  • ◯ Monochrome monitors were controlled via two signals (video, intensity) and two synchronous signals (HSync + and VSync-)
  • Graphics Color Graphics adapter monitors via four signals (Red, Green, Blue, Intensity) and two synchronous signals (HSync + and VSync-)
  • ◯ Enhanced Graphics Array monitors with six signals (Red, Green, Blue, Red-Intensity, Green-Intensity, Blue-Intensity) and two synchronous signals (HSync + and VSync-)
• • era 3rd : With the video graphics array, IBM once again used only one line per color (red, green, blue), via which the intensity was transmitted in analog form. Up to 2 ¹⁸ colors were supported. The two synchronization signals were retained.
• • era 4th : Digital transmission of analog signals as digital data over 1 or 2 lines. Synchronous signals as special code words in the digital data stream.
• • era 5 : In era 4th the signal with the exact timing from era 3rd transfer. You also break away from this habit and transmit video data as asynchronous packets.

Sync signals

Computer monitors usually require separately transmitted synchronization signals (HSYNC + VSYNC). Rarely are both signals transmitted together (CSYNC). Transmission with the brightness signal (YUV) or Sync-on-Green, the standard for video, is not used.

Flat screens

DVI plug and socket

Digital Visual Interface (DVI) is an interface for the transmission of video data. In the PC area, DVI developed into a standard for connecting TFT monitors to the graphics card of a computer. DVI includes the simultaneous output of analog (DVI-A or DVI-I) and digital video signals (DVI-D and DVI-I). DVI is widely compatible with the HDMI that was created later.

High definition multimedia interface

High Definition Multimedia Interface (HDMI) is an interface developed from mid-2003 for the fully digital transmission of audio and video data in consumer electronics. It unifies existing processes, increases the quality features compared to them, and also offers a coherent copy protection concept (DRM).

DisplayPort

DisplayPort (DP) is a universal and license-free connection standard standardized by VESA for the transmission of image and sound signals. Areas of application are essentially the connection of screens and television sets to computers and similar devices.

Quo vadis

The path is clearly marked towards a general interface that is capable of both power supply and data transmission as well as the output of video data. See USB 3.1 with Type C connector, Mobile High-Definition Link (MHL) and Thunderbolt.

Analog TV

Serial digital interface

The Serial Digital Interface (SDI) is a serial digital interface, primarily for the transmission of uncompressed and unencrypted video data via coaxial cable or optical fiber. It is mainly used in the field of professional television studios and television stations.

The SDI interface is specified by the Society of Motion Picture and Television Engineers (SMPTE) and represents a further development of the analog video standards such as the PAL or NTSC process.

Technical types according to the type of imaging process

Raster displays vs. Vector displays

Grid displays cover the entire screen in a fixed grid. The electron beam is scanned light or dark, depending on the representation.
→ Main article: vector screen

Vector screens work like a plotter. It is difficult to display areas, but very good lines. Above a certain level of complexity in the display, the image flickers increasingly because the drawing takes too long and the image can be written less than 40 times per second.

Tube monitors
→ Main article: cathode ray tube screen

Flat displays: liquid crystal screens (or plasma displays)
→ Main article: liquid crystal display

While newer LCD computer monitors and HDTV monitors all have square pixels, old LCD computer monitors and SDTV screens have both square and non-square pixels. Non-square pixels were common in early CGA and EGA laptop displays. SDTV monitors were often based on the ITU-R BT.601 and had 352, 704 or 720 pixels horizontally. Neither at 4: 3 nor at 16: 9 nor at PAL nor at NTSC were the pixels square.

Data transfer

The connection to the TFT monitor is not only a question of compatibility, but also of the quality of the picture. DVI is a digital interface for graphics cards and monitors (Digital Visual Interface). VGA is the analog interface (video graphics array). The graphics data are digitally processed in the PC, which are then converted into analog signals in the graphics card.

A TFT monitor requires digital signals to display the images. If a TFT monitor is now operated via a VGA connection, an analog-digital converter in the monitor must translate the analog signal into a digital signal. Due to the conversion, the quality of the image is more or less subdued depending on the components used. Slight blurring and flickering may result. The best combination is a graphics card with digital DVI output and a monitor with DVI input. Via DVI-VGA adapter a TFT monitor, which only has a VGA connection, can also be operated on a graphics card with a DVI connection, but with this method the image is still transmitted analogously.

Standard resolutions

In the area there are both graphic standards and typical resolutions for graphic modes, most of which are standardized via VESA.

The screens are factory-adjusted to a gamma of 2.2 and a color temperature of 6500 K. Using color management software, these values can be adjusted (as far as possible).

Like tube screens with cathode ray tubes, flat screens have a maximum and minimum displayable screen resolution. While in a tube monitor no resolution fits exactly over the native shadow mask and therefore all resolutions are reproduced accordingly out of focus. Most other resolutions need to be interpolated and therefore appear less sharp. Exceptions are resolutions that divide the maximum resolution in terms of height and width and therefore do not need to interpolate intermediate pixels, such as half or a quarter of the native resolution. The native resolution is specified in the type description of the monitor.

As the desktop screen resolution of the operating system, the native (= maximum) screen resolution of the flat screen monitor used is particularly recommended today. Modern operating systems take on the scaling of the screen display itself to the desired display size, and thus enable the graphics card to control the flat screen in its native resolution.

Screen dimensions

The exact screen diagonal is specified for TFT monitors. In earlier tube monitors, the (not fully usable) diagonal of the glass bulb was specified. This diagonal was about 2.5 to 4 cm larger than the really usable diagonal.

The aspect ratio for tube monitors was almost (?) Without exception 4: 3. At the beginning this was also the case with flat displays. 17-inch and 19-inch devices were usually available with a resolution of 1280 × 1024 and an aspect ratio of 5: 4. As of the advent of 24-inch devices around the turn of the millennium, 16:10 were added and 16: 9 devices since 2008. The latter now have a market share of around 90 percent.

Another size was the maximum line frequency or the maximum frame rate for a given resolution. Since the TFT era, this has become less important and is usually 60 Hz. Flicker has nothing to do with the refresh rate of the image content.

Liquid crystal display

A liquid crystal display (LCD) or a liquid crystal screen is a display or a screen, the function of which is based on the fact that liquid crystals influence the polarization direction of light when a certain amount of electrical voltage is applied.

LCDs consist of segments that can change their transparency independently of one another. For this purpose, the alignment of the liquid crystals is controlled in each segment with electrical voltage. This changes the permeability to polarized light that is generated with a backlight and polarization filters.

If a display should be able to display any content, the segments are arranged in a uniform grid (see pixels). In the case of devices which are only intended to represent certain characters, the segments often have a shape which is specially adapted to them, in particular in the case of the seven-segment display for displaying numbers (see also matrix display).

A further development is the active matrix display, which contains a matrix of thin-film transistors (TFT) for control purposes. This technology has dominated flat panel displays since around 2005.

LED TVs have been widely used in advertising since around 2009. In most cases, these are also liquid crystal screens (LCDs) for image display, in which LEDs are used for backlighting (LED backlight). Screens with organic light-emitting diodes (OLEDs) have only recently become available for large-area television sets in Europe, after initially only serving the test market in South Korea.

LCDs are used on many electronic devices, such as consumer electronics, on measuring devices, mobile phones, digital watches and pocket calculators. Head-up displays and video projectors also use this technology.

history

In 1904 Otto Lehmann published his main work Liquid Crystals. ^[1] In 1911, Charles Mauguin described the structure and properties of liquid crystals. In 1936, the American Marconi Wireless Telegraph Company received a patent for the first practical application of the technology, the liquid crystal light valve. In 1962, George William Gray published the first important English-language publication on the molecular structure and properties of liquid crystals (Original: Molecular Structure and Properties of Liquid Crystals).

Pioneering work on liquid crystals was carried out by the British Radar Research Establishment in Malvern in the late 1960s. The team there supported the progressive work of George William Gray, who with his team at the University of Hull in Kingston upon Hull (England) finally synthesized liquid-crystalline cyanobiphenyl compounds that met the requirements for stability and temperature behavior for LCD.

The first functioning LCD was based on the dynamic scattering mode (DSM) and was introduced in 1968 in the USA by a group at the Radio Corporation of America (RCA) under the direction of George H. Heilmeier. Heilmeier founded Optel, which developed some LCDs based on this principle.

On December 4, 1970, Martin Schadt and Wolfgang Helfrich, then working in the Central Research Laboratory of Hoffmann-LaRoche, registered the first patent for the "nematic rotary cell" (also TN cell, Schadt-Helfrich cell, twisted nematic field effect) in Switzerland. ^[2] The patent was granted in 21 countries, but not in Germany.

On April 22, 1971, James Fergason of Kent State University in the USA filed his patent application for the twisted nematic field effect in liquid crystals ^[3] and in 1971 employed LCD in his company ILIXCO, which is today (2005) LXD Incorporated Technology. They quickly replaced the worse DSM types.

Ideas that are used today in active matrix displays came from the conception of liquid crystal bar displays. In 1971, an LC matrix display for bar graphs was developed by Brown, Boveri & Cie, Baden, Switzerland, with a diode (non-linear element) connected upstream of each LC segment and an additional capacitor connected in parallel as a storage element. ^[4]

On June 28, 1973, a patent for an arrangement for bar display was registered in the USA, in which interdigital electrodes are attached to only one glass plate in order to generate an electric field parallel to the glass plate and to reorient (one-plane) the liquid crystals in one plane switching, IPS, see display types). ^[5]

On July 7, 1983, with an addition from October 28, 1983, H. Amstutz and his co-inventors of the research center of Brown, Boveri & Cie, Baden, Switzerland, filed a patent application ^[6], which formed the basis for Super-Twisted Nematic STN -LCD formed (see display types). With STN-LCD, monochrome, passive matrix displays with sufficient resolution for simple image display could be realized for the first time (see display of a world map under electronic control). This patent has been granted in many countries. Asian manufacturers in particular became licensees (over 60 worldwide).

On January 9, 1990 G. Baur and his co-inventors reported to the Fraunhofer-Gesellschaft in Freiburg i. Br. A patent in Germany, ^[7] which provides the concrete basis for optimized in-plane switching in Matrix displays (IPS-LCDs) made. This patent was granted in many countries, taken over by Merck KGaA Darmstadt, the world's largest manufacturer of liquid crystal substances, and licensed to many companies.

On September 18, 1992 with an addendum of January 20, 1993, K. Kondo and his co-inventors filed a patent application with Hitachi in Japan, ^[8] which, as a further essential element of in-plane switching, presented a specifically suitable connection technique for thin-film transistors in matrix form. Another Hitachi patent application was filed later, which improved the viewing angle dependency of this type of LC displays.

Display types

Schadt-Helfrich cell / Enlarged subpixels (TN panel) Enlarged subpixels (multi-domain VA panel)

Twisted Nematic (TN)

Liquid crystals used in liquid crystal displays are organic compounds which have properties of both liquids and solids. On the one hand, they are more or less fluid than a liquid, on the other hand they have properties such as birefringence.

A simple liquid crystal display element can be implemented with the Schadt-Helfrich cell (nematic twisted nematic, TN cell). In the illustration opposite, only the components of the lower half of such a rotary cell are numbered. The reference numbers (x) are inserted in this description. The inside of two very thin glass plates (substrates) ( 4th ) are coated with a transparent electrode layer (indium tin oxide layer, ITO) (3), in between is the liquid crystal layer ( 1 ) less than 10 microns thick. The liquid crystal molecules arrange themselves in a predetermined direction, namely parallel to that with, for example, a polyimide ( 2nd ) coated and brushed in a preferred direction. The preferred directions of the two substrate plates are rotated by 90 ° to each other. In the manufacture of handmade prototypes, polystyrene foam or rollers coated with velvety textiles can be used for brushing.

In addition, the two substrate plates ( 4th ) with polarization filters rotated by 90 ° to each other ( 5 ) coated. On the back of this arrangement, a mirror ( 6 ) are located (reflector or transreflector), which reflects the incident light (reflective mode). In the transmissive operating mode, a lighting unit is located behind the display element instead of the reflector.

A helical structure in the liquid crystal results from the twisted substrate plates; with a screw turned by 90 ° one speaks of TN. Incident light is thus linearly polarized before entering the liquid crystal layer. The twisting of the molecules results in a rotation of the polarization direction of the light, so that the light can pass through the second polarizer and the cell is translucent (transparent). Since the display is transparent in the idle state, this operating mode is referred to as normal white mode. If an electrical voltage is applied to the electrodes, the liquid crystal molecules rotate under the influence of the electric field and align themselves parallel to the electric field. The twisting is thus increasingly eliminated, the direction of polarization of the light is no longer rotated and it can therefore no longer pass through the second polarization filter.

If the polarization filters are arranged parallel to one another, the cell is dark without voltage and only becomes transparent with increasing voltage. One then speaks of the normal black mode. The Schadt-Helfrich cell is (like other liquid crystal displays) a voltage-controlled light valve. A screen can consist of any number of such cells (picture elements, pixels). In the pocket calculator, a simple 7-segment display represents one digit each; in the case of a color-capable screen, three sub-picture elements (sub-pixels) are used for the basic colors red, green and blue for each picture element (pixel).

Super Twisted Nematic (STN)

With (monochrome) STN (super twisted nematic) displays, the twist angle of the molecules is increased to 180 ° to 270 °. As a result, a steeper electro-optical characteristic and thus an improved multiplexability than with TN displays can be achieved. Due to various technical restrictions, it is only possible with some effort (double cell = DSTN cell, compensation with birefringent retarder sheets - retarder sheets) to make the display neutral in color (ie only grayscale between black and white). Instead, the light states are yellowish and the dark states turn dark blue (with a violet tone). A further development is CSTN (color super-twist nematic) by Sharp, in which filters in the three primary colors red, green and blue in front of the pixels are used for the display of colors.

Double Super-Twisted Nematic (DSTN)

Attempts were made to achieve a black-and-white display on the passive matrix display using various techniques: with the guest-host technology, Martin Schadt's OMI method ("Optical Mode Interference") and the double super -Twisted technology. The latter has established itself as DSTN technology.

The principle of construction of this DSTN cell can be seen in the picture. There are now two STN layers. In the active cell - that is the one to which an electric field can be applied - the liquid crystal is rotated by 240 ° counterclockwise. The passive cell also contains nematic material, but here it is rotated by 240 ° clockwise. Both cells are rotated relative to each other so that the orientation of the rods on the input side is perpendicular to that on the output side. The polarizing foils are also rotated 90 ° against each other.

Structure of a DSTN liquid crystal cell

In the conventional TN or STN cell, strictly speaking, after the passage of linearly polarized light, it is not simply linearly polarized light with a twisted oscillation plane that is obtained, but elliptically (or circularly) polarized light. The tip of the electric field vector describes an ellipse or a circle. Such light passes through the polarizer, the color splitting caused by the dichroism - depending on the polarization and the film orientation at the beam exit - leading to colored light.

About the function of DSTN cells

The image shows how DSTN-LCD works: White light falls on the rear polarizer (in the image below) and is linearly polarized there. Then it gets into the active STN cell, which (without field) now generates circularly polarized light from it. As with the conventional STN cell, this light is changed by dichroism. The path through the subsequent passive cell (which contains the same liquid crystal material as the first - active - cell, but twisted in the opposite direction) leads to compensation of the color splitting (the phase difference becomes zero). The result is linearly polarized light which has the same plane of vibration as before after passing through the rear polarizing film. However, because the front polarizer is rotated by 90 °, it does not let light through: the screen is black at this point.

If there is an electric field on the active cell, the linearly polarized light from the rear polarizer passes through there smoothly without being changed. Circular polarization only occurs in the passive cell. However, because circularly polarized light is not retained by polarizers, the screen is bright at this point. By precisely adjusting both the material used and the cell dimensions, the transmitted light becomes white.

In this way, displays were realized that offer a clean black and white with a contrast ratio of up to 15: 1.

Triple Super-Twisted Nematic (TSTN; nowadays referred to as TN or film TN) Structure of a TSTN liquid crystal cell: the light of the lighting ( 6 ) is polarized (2), filtered (3), passes through the rear glass pane ( 4th ), the STN liquid crystal ( 5 ), the front glass pane ( 4th ), the front filter foil ( 3rd ), the front polarizer ( 2nd ) and finally emerges in color (1).

The complex structure of a DSTN liquid crystal cell requires a relatively high effort in its manufacture. A new process was therefore developed which leads to flatter displays with less weight. This new solution is called the "Triple Super-Twisted Nematic" LCD (TSTN). The picture shows the construction principle of such a TSTN display.

There is only one STN-LC cell here. The color disturbances of normal STN technology are compensated for by two special foils, which are attached in front of and behind the cell - between the polarizer and glass. These foils are responsible for another name of this technique: FST, which means "film super-twisted" (occasionally one calls displays, in which only one compensation foil is used, as FST, those with two or more foils as TST-LCD; the term FSTN for film STN is also common). The improved contrast (up to 18: 1), the lower weight and the flatter and less complex design have helped TSTN-LC displays to break through. Such displays were first realized as "VGA screens" in notebook computers.

Vertical alignment (PVA and MVA)
→ Main article: Multi-domain vertical alignment

The patterned vertical alignment technique, also called PVA for short, is a further development of a manufacturer's multi-domain vertical alignment technique (MVA). Both techniques are based on a similar process. The advantages of MVA / PVA screens are in a higher contrast (> 1000: 1 is common) than with a TN screen (<800: 1). In addition, MVA / PVA screens offer great viewing angle independence. The disadvantage of MVA / PVA screens is that they are slower than TN screens and therefore less suitable for moving images - such as games and videos. In addition, the price is higher than that of TN screens.

In-Plane Switching (IPS)

With in-plane switching technology (IPS, English for switching in the plane), the electrodes are located next to each other in a plane parallel to the display surface. When the voltage is applied, the molecules rotate in the screen plane; the screw shape typical of TN displays is omitted. IPS reduces the viewing angle dependence of the contrast. ^[9]

A distinction is made between sub-types between S-IPS (Super IPS), AS-IPS (Advanced Super IPS), A-TW-IPS (Advanced True White IPS), H-IPS (Horizontal IPS), and since 2009 E-IPS (Enhanced IPS) ) and since 2011 AH-IPS (Advanced High Performance IPS). Except for the H-IPS type, the other IPS types can be recognized by the fact that, viewed from the side and in contrast to VA panels, they have a light purple color. The E-IPS technology, which came onto the market in 2009, offers an even wider viewing angle and shorter switching times of 5 milliseconds.

The further development PLS (Plane-to-Line Switching) was developed by Samsung and offers, among other things, greater transparency (lower power consumption with the same brightness) and the elimination of the glitter effect typical of IPS panels. The first screens with PLS panels came on the market in 2011.

Electronic control

The first prototype LCDs in the early 1970s recognized that direct current operation can cause irreversible electrochemical processes in the liquid crystal layer and thus limit the lifespan of the display. Although, in contrast to LCDs according to the dynamic scattering mode (English, DSM), TN cells are an electrical field effect, meaning that no current flow is necessary, the problems mentioned when applying a DC voltage still existed. For this reason, all commercially used LCDs were operated with AC voltage for a long time. An LCD element is essentially a small electrical capacitance which is periodically recharged by a pulse-like electrical voltage. For this purpose, the electronic complementary MOS circuits (CMOS ICs) that were already available at that time were excellently suited both with regard to the adjustable voltage swing and the symmetry of the properties. One of the advantages of TN cells is the low operating voltage and thus the low power consumption. Liquid crystal substances for TN LCDs were synthesized early on, which gave good contrast when operated at 3 volts and had a usable operating temperature range. ^[10]

The operation of passive matrix displays depends on how pronounced an electro-optical threshold voltage is. Because the control of the individual picture elements (pixels) has to be repeated periodically in order to control not only one line but all pixels of a matrix. B. the rows of a matrix are driven sequentially in pulse form. In the columns, the image information is input in such a way that the greatest possible voltage difference to the line pulses occurs in the activated picture elements and a voltage difference below the threshold value arises in the non-activated picture elements. Decisive for the optimization was the finding of Peter J. Wild, ^[11] that the root mean square (RMS) of the voltage differences is decisive for pulse-like, periodically repeated control. ^[12] Detailed information on the best possible control techniques for passive matrix displays can be found in further literature. ^{[13] [14]}

As already mentioned, an electro-optical characteristic curve with a pronounced threshold value and then a steep rise at a higher voltage is a prerequisite for realizing passive matrix displays with many rows and columns. This is the only way to achieve sufficient contrast even with matrices with many pixels. The lengthy optimization of the voltage-contrast characteristic curve through liquid crystal substance selection and cell structure of TN cells did not produce the desired results. It was over 10 years before the breakthrough came in 1983 with the discovery of super-twisted nematic LCDs (English super-twisted nematic Icds, STN-LCDs) at Brown, Boveri & Cie, Baden (today Asea Brown Boveri, ABB) ^[15] Die The characteristic curve of STN cells is much better suited for driving passive matrix displays than that of TN cells.

It was attempted relatively early to individually switch switching transistors upstream of each pixel in order to circumvent the characteristic curve limitations of a passive matrix display. For this purpose, thin-film transistors (TFT) of suitable dimensions and connection technology had to be applied in a matrix arrangement on the glass substrate of the liquid crystal display. A display of this technique is called an active matrix display because the operation of the individual pixels is actively controlled by the assigned transistors. Although the ideas for this had already been formulated at the Radio Corporation of America (RCA) and Westinghouse Research Laboratories, USA, from 1968-1973, ^{[16] [17]} it was still a long time before the technological requirements for mass production were worked out. In particular, experiments were carried out with various semiconductor materials until a special type of amorphous silicon (see thin film transistor) finally emerged as the most suitable for field effect transistors in thin film technology. This material breakthrough came in Europe. ^[18] In the implementation of commercial products, Japanese companies were responsible. Large-scale television liquid crystal displays would not have been possible without the advances in electronic control mentioned above. However, due to the numerous additional process steps for TFTs, active matrix displays are more expensive to manufacture and can therefore also have pixel errors, so that passive matrix displays are still used for simpler displays with less information content.

Contacting

From the start, the task was to connect the transparent conductor tracks on both LCD glass substrates to the control electronics. Novel connection technologies were developed for this.

So-called zebras (see conductive rubber) are used for displays with a contact pitch that is not too narrow, which alternately consist of insulating and conductive elastomer “channels”. In the picture on the left with a comparison scale in cm, the dark grid of the zebra rubber of 180 micrometers is therefore only visible when the image is clicked with an enlargement: in the pink-red isolating elastomer band are the black guide elements, separated by isolating elements. Due to the structure (the elements are much smaller than the surfaces to be contacted), positional tolerances of the rubber do not matter. The rubber can absorb dimensional tolerances. Typical applications are displays with seven-segment displays.

Solutions with chip-on-glass were also tried out early on. ^[19] Solder points were applied to the contacts of the control circuits, then the chip was positioned on the corresponding contacts on the display and then soldered at an elevated temperature.

An important advance was the use of flexible, thin printed circuit boards with corresponding connecting tracks for the display, which allow a very close contact grid. These circuit boards also often carry the ICs as bare chips (flip-chip assembly) that convert the digital serial data streams.

Passive matrix displays

In passive matrix displays, the picture elements (a segment or a symbol) are activated in time-division multiplexing. This means that each picture element is directly and permanently connected to a control circuit whose output has a low resistance. For this reason, the charge applied at the time of addressing degrades relatively quickly and has to be renewed in the following frame period. This change in the electrical control leads to pronounced modulations of the optical response of the display (so-called frame response).

In the case of addressing and control via a matrix with active components in active matrix displays, a charge is applied to the picture element at the time of addressing, to which an additional capacitor is usually connected in parallel (storage capacitor). After applying the cargo, the amount of which corresponds to the data information, the active component (usually a thin-film transistor, TFT) is switched back to the high-resistance state, as a result of which the charge and thus the activation is essentially retained during an image period.

In the case of active matrix displays, this type of control brings about a higher effective voltage across the picture element, thus a higher modulation of the liquid crystal and thus an improved contrast and a reduced dependence of the contrast on the viewing direction.

1. 1. Geringere Leistungsaufnahme: Unabhängig vom Bildinhalt werden LC-Bildschirme über die gesamte Anzeigenfläche konstant beleuchtet. Trotz dieser prinzipiellen Schwäche ist die Lichtausbeute (englisch luminous efficacy) bei LCD mit typisch 2 bis 4 Im/W noch immer etwa doppelt so hoch wie bei Plasmabildschirmen mit Filterscheibe (normaler Auslieferzustand).
2. 2. Strahlungsarmut: LCD strahlen keine Röntgenstrahlung ab (gilt auch für CRTs ab TCO 99) und erzeugen ein geringeres Magnetfeld. Elektromagnetische Felder werden jedoch abgestrahlt und enthalten ebenso wie bei CRTs die Bildinformation (sog. kompromittierende Abstrahlung, Problem Abhörsicherheit, s. Van-Eck-Phreaking).

The LC screens have several advantages over the older cathode ray tube (CRT) screens.

1. 1. Lower power consumption: Regardless of the image content, LC screens are constantly illuminated across the entire display area. Despite this fundamental weakness, the luminous efficacy of LCDs with typically 2 to 4 Im / W is still about twice as high as that of plasma screens with a filter disc (normal delivery condition).
2. 2. Low radiation: LCD do not emit X-rays (also applies to CRTs from TCO 99) and generate a lower magnetic field. However, electromagnetic fields are emitted and, like CRTs, contain the image information (so-called compromising radiation, problem of security against eavesdropping, see Van Eck phreaking).

In addition, they have a flicker-free, distortion-free, sharp image with ideal resolution, a lower weight and a low installation depth.

In contrast to display devices with a cathode ray tube, liquid crystal displays are in practice not affected by magnetic fields such as the earth's magnetic field or the magnetic fields of overhead lines, NMR devices, transformers or loudspeakers.

During the development of the devices, at least until the development of LCDs controlled by TFTs, there were disadvantages due to the low contrast and the long switching times. In the meantime, the color rendering of LCD (the color gamut that can be displayed) can even meet extreme requirements by adjusting the backlighting (extended gamut, multi-primary display). Another problem was the limited range of viewing directions with constant contrast and color impression; Newer technologies such as in-plane switching (IPS), multi-domain vertical alignment (MVA) and patterned vertical alignment (PVA) as well as the use of birefringent compensation foils (retarder sheets) have remedied this. These disadvantages continue to exist, but are nowhere near as serious as they used to be. Since each pixel represents its own small unit, production-related errors (pixel errors) occur: pixels that consistently light up in only one color or incorrectly reproduce the specified color. Depending on the number of defective pixels, the displays are classified in different error classes, which can influence the price.

The physical image resolution is determined during production; control with a signal of a different resolution can lead to quality losses. A TFT-based LC screen provides a much sharper picture than a CRT screen - but only in its design-related physical resolution. Lower resolution signals must be interpolated and appear blurry. Alternatively, the image can also be displayed with black edges centered in full focus (with a digital connection, this can usually be set in the graphics card driver).

The backlighting through so-called cold cathode tubes is filtered in order to preserve the basic colors of the pixels (mostly red, green and blue), however the compromise between brightness and color rendering quality has to be found. The colors of LCD are by no means less saturated than with CRT or plasma display technology. Only about 4% of the generated light penetrates through the panel (with white picture content). ^[20]

One reason why tube monitors (CRT) often perform better than flat screens in tests is not the better black level in the dark and the contrast to the bright areas of the image when no ambient light falls on the screen, but rather the better reproduction of moving image content (see below ). In the meantime, however, LCD technology has progressed so far that sometimes even better results (depending on the type of panel) can be achieved than with CRT monitors.

The backlight fluorescent tubes have a limited lifespan (approximately 100,000 hours). The quality of the display of white areas, which is influenced by the backlight, already changes significantly more yellowish after only a few thousand hours of operation, since the luminosity of the fluorescent tubes decreases over time. However, the brightness of tube monitors also decreases during operation. The backlighting by means of LEDs is more resistant to aging, but it also shows slow signs of aging depending on the type of light emitting diodes used and the mode of operation. In addition, lighting by means of LEDs enables a more compact design, more homogeneous illumination and increased contrast through selective control depending on the image content (LED backlight).

Switching times and techniques

The response time of modern LCDs is currently between 1 ms and 5 ms. Here, the response time is the time that elapses when the luminance (brightness) of an image area changes from 10% to 90%; 0% and 100% are the luminance of the steady state. The image build-up time according to ISO 13406-2 is the sum of the switching times from light to dark (or vice versa) and back again. Due to the asymptotic switching process, switching times of <3 ms are required according to ISO 13406-2 in order to avoid visible streaking.

Formulas

The switch-on time (increasing voltage) and the switch-off time (decreasing voltage) result from the formulas of Jakeman and Raynes: ^[21]
with Here is the rotational viscosity of the liquid crystal, which describes the "inertia" of the liquid crystal to a change in orientation; the distance between the glass plates (= thickness of the liquid crystal layer); and the elastic constant, which indicates the “force” (torque) of the return of the crystals to the original alignment position.

For example, a large one accelerates the return of the crystal to its initial state, but also counteracts the alignment of the crystal when a voltage is applied (due to the correspondingly increased threshold voltage).

The switching speeds can also be increased by reducing the layer thickness. If, for example, the layer thickness is reduced by 30% (), the switching times decrease to about half (because).

Motion blur

In the case of hold-type displays such as LCD and OLED screens, the state of a pixel remains for the duration of one picture period until the applied voltage is changed in the course of the picture construction of a new picture (maintenance representation). Since the eye integrates the "brightness" over a period of the image when tracking a moving image content (English smooth pursuit eye tracking), but the image content remains fixed, the image is blurred on the retina of the viewer. This is particularly noticeable when displaying fast moving scenes and is therefore also referred to as motion blur. It should be noted that even with vanishingly short switching times, i.e. with almost infinitely fast switching, the motion blur would not be eliminated due to the conservation display, which is why the wiping effect also occurs with fast OLED screens.

In addition to this principle-related blurring, the delayed acceptance of the target value for individual pixel elements also creates undesirable effects ("streaking", "tail", "smearing") that have a similarly disturbing effect. With today's LCDs, this type of motion blur is already considerably reduced. The response time from “gray to gray” is 6 ms on average, but the switching times can vary considerably in extreme situations (white-to-black, black-to-white, black-to-gray) .

Approaches to optimization

viscosity
One of the ways to counteract the motion blur is to further reduce the switching times of the displays, especially by reducing the viscosity of the liquid crystal materials used.

Simple overdrive technologies
With overdrive technology, a voltage is briefly applied to the LCD cell that is higher than that required for the actual brightness value. As a result, the crystals align faster. The next picture has to be saved. This information is used together with correction values specially adapted to the respective display in order to be able to calculate the exact time during which the overvoltage may be present without the respective pixel being overdriven. However, this does not work when the crystal is reset: since there is no less than no voltage (the control takes place with AC voltage), the crystal must relax passively. Due to the intermediate storage, the image is displayed about two to five measures late. This offset can become noticeable when watching films due to picture-sound asynchrony (the sound rushes ahead of the picture). Image buffering also has a negative impact on computer games that require quick reactions from the player.

Predistortion (inverse filtering)
The integration of the eye from the next image is calculated from the data of the current and next image. The exact switching properties of the respective panel type are also required for this.

Black stripe insertion
In order to counteract the motion blur due to the preservation display, the pixels or the entire display can also be darkened for a short time. However, the dark phase at 50 Hz control frequency must not exceed 55% of the picture time (at 60 Hz it is 70% and at 75 Hz it is 85%): otherwise the picture flickers.

Blinking backlight
Also called “strobing”: When using LEDs for backlighting LCDs (so-called LED TVs or screens), this method is easier to implement than black stripe insertion, since it is not necessary to control the pixels faster, but for pixel areas or the entire display the backlight can be turned off for a fraction of a full screen.

Scanning backlight
also called "field sequential": Here the LC display is not illuminated with white light, but successively with red, green and blue primary lights (often by LED). Since LCDs with time-sequential control with the primary colors do not require any brightness-reducing color filters and high luminance levels, the loss of brightness can be more easily compensated for by the sequence sequence. However, with this technique you meet an old friend of projection technology: the rainbow effect.

100/120 Hz technology and 200/240 Hz technology
Here synthetic intermediate images are calculated and then output together with the original images. This increases the real frame rate by an integral multiple. 24 fps (cinema standard) becomes 48, 72, 96 or even 120 fps. Streaks through hold displays can thus be significantly reduced. In addition to reducing motion blur, movements and tracking shots are reproduced much more smoothly. However, due to the motion interpolation, a more or less clear separation between foreground and background can be observed in the image, especially with slightly noisy image sources (soap opera effect). The 100/120 Hz technology is now (2008) used in many high-quality displays. 240 Hz devices have been announced. Another advantage of this technique is that overdrive can be applied in finer doses. However, it should be noted that the greatest improvement can be seen between the "100/120 Hz displays" and those with lower frame rates, since the human brain can only consciously process larger differences between the frequencies without practice.

Possible uses

LCDs have been used in digital clocks and calculators since the early 1970s. These single-color displays without backlight are characterized by the lowest energy consumption and very long service life and can be used wherever long maintenance-free operation is required.

Later, LCDs as active matrix displays with backlighting were spread via other portable or battery-powered devices such as cell phones, notebooks and the like.

Typical resolutions for computer flat screens range from 1024 × 768 pixels (38 cm / 15 ") to 2560 × 1600 pixels (76 cm / 30"), up to 3840 x 2160 pixels, for notebooks they range from 800 × 480 pixels to 3200 × 1800 pixels. PDAs and portable DVD players have resolutions between 320x240 and 800x480 pixels, displays of still and video cameras between 160 × 176 pixels (84 thousand pixels) and 640 × 480 pixels (900 thousand pixels). In the case of smartphones in particular, Apple has created a new marketing term for high image resolution with the “retina display”.

In the meantime, LCD and plasma displays have largely replaced the cathode ray tube. This applies to computer monitors (since 2006) and televisions with larger screen sizes (since 2008). Other areas of application, such as oscilloscopes, have long been in the hands of computer-controlled LCDs. In 2003, more LCDs were sold in Germany than conventional tube monitors for PCs ^[22], and in 2006 more flat-screen TVs - in other words, LCD and plasma screens - were sold as tube sets. ^[23]

Attempts to realize screen projectors with LCD matrix displays began in the 1970s. ^[12] The Imagina 90 was the first mass-produced Video large screen projector with liquid crystal image generator that was also suitable for continuous operation worldwide.

production

LCD technology has seen an enormous boom in recent years, particularly as a result of the development of flat screens. Large production facilities for flat screens were initially built in Japan. However, the emigration of the industry to the new Asian industrialized countries, where cheap labor and generous government subsidies lured, soon began. The focus of the flat panel display industry is currently in Taiwan and especially South Korea. In South Korea, the world's largest flat screen manufacturers based there - Samsung, LG Display and Chi Mei Optoelectronics (CMO) - operate the currently (2008) largest LC screen production plants. However, the migration of the industry continues.

The boom has now reached China in search of even more cost-effective production locations. Production facilities for the production of high-quality flat screens are currently under construction there (2008). ^[24]

environmental Protection

From the point of view of climate protection, liquid crystal screen production is regarded as problematic, since very large quantities of substances that are harmful to the climate are used in traditional production. In the important “array process”, in which the TFT control matrix is applied to thin glass panes over a large area, potent greenhouse gases such as sulfur hexafluoride (SF ₆ ) - GWP 22800 CO ₂ e - and nitrogen trifluoride (NF ₃ ) - GWP 17200 CO ₂ e - are very much used extensively and released into the atmosphere, as a study from 2008 shows. ^[25]

• • Cholesterische Flüssigkristallanzeige (ChLCD)
• • Ferroelectric Liquid Crystal Display (FLCD)
• • Fransenflügler beschädigt Monitore

See also

• • Cholesteric liquid crystal display (ChLCD)
• • Ferroelectric Liquid Crystal Display (FLCD)
• • Fringed wing damages monitors

software

Software [‚sɒf (t) wε:] (German = soft goods [from] soft = easily changeable components [...], complement to, hardware 'for the physical components) ^[1] is a collective term for programs and associated data. ^[2] As an accessory, you can also add components such as B. containing the software documentation in digital or printed form of a manual ^[3]

Software determines what a software-controlled device does and how it does it (roughly comparable to a manuscript). ^[4] The hardware (the device itself) executes software (executes it) and thus implements it. Software is the entirety of information that must be added to the hardware so that a software-controlled device can be used for a defined range of tasks. ^[5] The software-controlled working principle means that rigid hardware can work individually. Today it is not only used in classic computers, but also in many embedded systems such as washing machines, mobile phones, navigation systems and modern television sets.

definition

The term software has not yet been uniformly defined, nor has it been clearly defined. This is due, among other things, to the fact that "within [...] software engineering, a uniform, solid, consistent and systematic definition of terms is hampered by a high rate of innovation and practical relevance". ^{[6]: 22} There are therefore various definitions which, depending on the author and context, often differ only in details.

In general, the term software is usually only used to refer to programs, but not to other data. ^{[7] In} addition, the source text, further data ^[2] or the documentation ^[3] can also be added depending on the definition.

In addition, software is also used as a generic term for different types of programs (graphics software, application software, standard software, security software and many others).

etymology

The term software is an artificial word that was first used by John W. Tukey in 1958 in the American Mathematical Monthly ^[8] as a counterpart to the much older word hardware. ^[9] Hardware refers to all the physical components of a computer. In this sense, software - as the counterpart to hardware - could basically be understood to mean all electronically stored data. ^[10] However, this view is not sufficient as a definition. ^[9]

Definitions according to ISO / IEC standard 24765

• • Software ist ein Programm oder eine Menge von Programmen, die dazu dienen, einen Computer zu betreiben.
• • Software sind Programme sowie die zugehörige Dokumentation.
• • Software sind Programme und ggf. die zugehörige Dokumentation und weitere Daten, die zum Betrieb eines Computers notwendig sind.

The current ISO / IEC standard 24765 replaced the DIN standard 44300 and contains the following definitions for software: ^[11]

• • Software is a program or a set of programs that are used to run a computer.
• • Software are programs and the associated documentation.
• • Software are programs and, if applicable, the associated documentation and other data that are necessary for operating a computer.

Which of these definitions applies depends on the respective context, whereby the transitions are also fluid here.

Software as a program

In software engineering, software consists of "computer programs in every form, from source code to directly executable machine code". ^[5] Computer programs often consist of several components, which can also be distributed over several files.

Software as program and documentation

In software law (often in connection with the acquisition of software), software is also referred to as a software product that “as an accessory, additional components such as. B. the documentation can or must contain in digital or printed form ”. ^[3] So also in copyright law, where the design material belongs to the software, ^[12] like the source text, also called source program. ^[13] That is, Copyright protection usually also applies to the source code [as subject of protection]. ^[14]

Software as a program, documentation and data

In addition to the program itself (and possibly the documentation), some definitions also provide further data that belongs to the software (“associated data” ^[2] ). The IEEE for software developers gives examples of such non-executable software parts, such as fonts, graphics, audio and video recordings, templates, dictionaries, documents and information structures (such as database data records). ^[15]

There are also software definitions that enclose all data that the computer program uses and also include the documentation. ^In contrast, there are also definitions that exclude both the documentation and the data provided for processing. ^[16]

However, a clear dividing line is not defined in more detail, which describes which data is specifically meant (e.g. the data to be processed) ^[4] or which data is necessary ^{[17] [9]} or, belonging ^[2] .

history

In the 1950s, software and hardware were still connected and perceived as a unit. The software was part of the hardware and was referred to as program code. In 1958, statistician John W. Tukey coined the term software for the first time. ^[8th]

Later, the decision of the US government in the 1970s caused a novelty that IBM had to calculate and list software and hardware separately on invoices. This corresponded to an acknowledgment of the solitary nature of software by the official side and a final splitting of hardware and software or a delimitation of the software from the hardware.

This development was followed in the 1970s by the founding of companies that for the first time only traded in software and only developed software and no hardware. These companies included Microsoft in the United States and SAP in Germany. The existence of such companies appears to be a matter of course in the 21st century, but was a significant innovation at the time.

The logical transition between hardware and software can be illustrated in the early arcade games, such as the game Breakout, which was published in April 1976. At that time, their complete program (the process, the logic) figuratively consisted of "pre-wired control panels". ^[18] The game hall device produced by Atari used no processor. Just a year later, when the game was programmed for the computer, and when processor-controlled devices started to differentiate between the terms 'hardware' and 'software', there was breakout as software. ^[18] The game was more of "pre-wired control panels", but of instructions for a processor including the necessary for the execution of other information that has been stored together on disk.

Special features of software

Software is immaterial

Software is immaterial and consists of the languages and notations in which it is formulated. ^{[9]: 37} Software can be saved, printed, displayed or transported on certain media. However, these are not the software, they only contain them.

Although it is conceivable to store bits visible and tangible on a carrier medium, 'software' is fundamentally an abstract term that is independent of carrier media. This applies to the generic term anyway, but also to specific forms such as a certain application program. ^[19] As an analogy, it is not conceptual for the term "opera" or "magic flute" whether it is performed in the theater, broadcast on radio / TV or sold or heard on CD, whether it is described in the opera guide or recorded in the score is.

• • Im Zusammenhang mit der Ausführung auf einem Computer wird unter Software primär alles verstanden, was auf dem Rechner ausgeführt werden kann (das Programm im engeren Sinn, bestehend aus Befehlen und Datendefinitionen). Dazu kommen die mit den Programmen verbundenen Ressourcen, die zum Betrieb der Software erforderlich sind. Das sind, abhängig von den verwendeten Entwicklungswerkzeugen, zum Beispiel Konfigurationsdateien, Schriftart-Dateien, Lookup-Tabellen, Datenstrukturen für Datenbanken etc.
• • In engstem Sinn wäre unter ‚Software‘ nur von der Hardware ausführbarer Maschinencode zu verstehen. Jedoch fällt darunter auch alles, was durch beliebige ,interpretierende Systeme‘, die Teil der Systemsoftware sind, ausgeführt werden kann, wie das bei Verwendung höherer Programmiersprachen und Entwicklungsumgebungen nahezu immer der Fall ist.^[9]
• • So ist in der Softwareentwicklung (als zentraler Arbeitsgegenstand) und in der Qualitätssicherung (als bedeutender Prüfgegenstand; siehe Softwarequalität) auch der Quellcode ein wesentliches Software-Artefakt.
• • Sprachlich wird der Ausdruck ‚Software‘ unterschiedlich verwendet: Er steht für konkret benannte Komponenten (Programm XY, Unterprogramm ABC, Konfigurationsdatei XXX.INI). Er wird als Sammelbegriff für unterschiedliche Gesamtheiten/Mengen von Programmen benutzt, zum Beispiel für eine aus vielen Einzelprogrammen bestehende Buchhaltungssoftware, für alle Anwendungen eines Unternehmens („unsere Unternehmenssoftware“), oder, wie bereits erwähnt, als Typ-/Gattungsbegriff für unterschiedliche Arten von Software (wie Grafiksoftware, Standardsoftware, Systemsoftware etc).

Different meanings in details

• • In connection with the execution on a computer, software is primarily understood to mean everything that can be executed on the computer (the program in the narrower sense, consisting of commands and data definitions). In addition, there are the resources associated with the programs that are required to operate the software. Depending on the development tools used, these are, for example, configuration files, font files, lookup tables, data structures for databases, etc.
• • In the narrowest sense, “software” would only mean machine code that can be executed by the hardware. However, this also includes everything that can be performed by any "interpreting systems" that are part of the system software, as is almost always the case when using higher programming languages and development environments. ^[9]
• • In software development (as a central work item) and in quality assurance (as an important test item; see software quality), the source code is also an essential software artifact.
• • Linguistically, the term 'software' is used differently: it stands for specifically named components (program XY, subroutine ABC, configuration file XXX.INI). It is used as a collective term for different groups / sets of programs, for example for accounting software consisting of many individual programs, for all applications of a company ("our company software"), or, as already mentioned, as a type / generic term for different types of Software (such as graphics software, standard software, system software, etc.).

Fluid boundary between software and data

• • Auf der Dateiebene können Mischformen auftreten, beispielsweise in Office-Dokumenten oder bei einer Tabellenkalkulationsdatei. Hier enthält eine Datei sowohl Daten im Sinne von das Bearbeitete (Texte oder Zelleninhalte) als auch funktionale Anweisungen (Makroanweisungen, Zellformeln).
• • Vertauscht sind die Rollen beispielsweise, wenn ein Quellprogramm von einem Compiler in ein Maschinenprogramm umgewandelt wird: Sowohl das Quellprogramm als auch das erzeugte Binärprogramm sind ,Daten‘, der Compiler ist die Software. Ebenso verwendet ein Interpreter ein Quellprogramm oder ein Emulator ein Binärprogramm als Daten und erzeugt daraus speicherintern den ausführbaren Code. Die so verarbeiteten Programmdateien sind Software, rollenspezifisch aber gleichzeitig Daten.

Data used for processing do not belong to the term software in general usage. ^[7] However, the boundary between software and data is fluid, because depending on the situation, data and programs can appear in different roles and the terms can be interchanged:

• • Mixed forms can occur at the file level, for example in office documents or in a spreadsheet file. Here, a file contains both data in the sense of what has been processed (text or cell contents) and functional instructions (macro instructions, cell formulas).
• • The roles are reversed, for example, when a source program is converted from a compiler into a machine program: Both the source program and the binary program generated are 'data', the compiler is the software. An interpreter also uses a source program or an emulator a binary program as data and uses it to generate the executable code within the memory. The program files processed in this way are software, role-specific but at the same time data.

This connection, that a program can appear both as data and as a function, is central in various computer science disciplines, including theoretical computer science (including recursion theory, automaton theory, domain theory) and technical computer science (e.g. Von Neumann architecture) ).

Differentiation between hardware and software

• • Leicht veränderbare Komponente (Software) vs. schwer veränderbare Komponente (Hardware) in einem Computerdesign.^[1]
• • Instruktionskode (Software) vs. Universelle Maschine (Hardware).
• • Nicht-greifbar im Sinne von Funktionsbestandteilen eines Computersystems, die sich „nicht anfassen lassen“^[20] (Software) vs. greifbare Komponenten (Hardware). Software ließe sich über eine Telefonleitung übertragen, Hardware dagegen nicht.

Depending on the context, the distinction between hardware and software means one or more of the following meanings:

• • Easily changeable component (software) vs. difficult to change component (hardware) in a computer design. ^[1]
• • Instruction code (software) vs. Universal machine (hardware).
• • Not tangible in the sense of functional components of a computer system that “cannot be touched” ^[20] (software) vs. tangible components (hardware). Software can be transferred over a telephone line, but hardware cannot.

The opposites are intended in the English language (soft = soft, hard = hard).

Different perspectives on software

• Zusammenwirken mit der Hardware (Execution)
• Software: Typisierung, Zusammenhänge, Überblick

Software can be viewed from many different perspectives, for example:

• Interaction with the hardware (execution)
• Software: typing, relationships, overview

"There is a certain division of tasks between hardware and software: The hardware guarantees [...] quantity, ie speed and storage capacity, the software ensures that the requirements are mapped to the structurally primitive hardware"

Although attributes such as flexibility, individuality, performance, etc. are partly attributed to the term "software", ultimately everything the computer actually does is not carried out by the software, but exclusively by the hardware. Software only describes what is to be done and in what form.

For this purpose, the machine code of the software is loaded into the main memory of the computer using the operating system (ie also by means of its machine commands) and fed to the arithmetic unit for execution step by step (see command counter). This principle of operation applies to all types of software, even if they are e.g. B. executed by interpreters: These are also software, the machine code of which is also executed on the hardware interface as described and which only generate the machine commands within the memory. Compilers, macro processors and any other type of system software are also executed according to this principle.

The machine code must be in a form / structure that can be interpreted and executed by the hardware via the interface implemented in it. ^[21] The commands show through their content and structure what needs to be done, which data areas in the main memory are to be used or changed (via addressing information contained in the command) and, if necessary, at which point the program is to be continued.

When it is executed, many layers work together and, as a whole, lead to changes in the state of the hardware or finally to the intended results, such as the output of a print line, data access or the display of field content on the screen. In applications developed in higher programming languages, hundreds of thousands or millions of machine commands can often be run through for relatively simple functions (such as reading from the database).

The parallel execution of several programs / processes that is possible in modern computers is essentially caused by the operating system, which initiates and manages the switch from one task to another when certain events occur. See also multitasking.

In the systematic interaction of many components, which is only possible using clearly defined interfaces, "software is one of the most complex artifacts that humans have created to date". ^{[9] 37}

The software also makes a significant contribution to how efficiently the hardware is used. Depending on the design of the algorithms, different system performance can be achieved with the same hardware.

Software development
→ Main article: Software engineering

Software development is a complex process. This is systematized by software technology, a sub-area of computer science. Here, the creation of the software is described step by step in a process from analysis to software modeling to testing as a repeatable process.

• • Software wird unter Nutzung bestimmter Verfahren, Methoden und ,Werkzeuge‘ entwickelt. Dabei werden unterschiedliche Entwicklungsstadien durchlaufen, in denen jeweils unterschiedliche Zwischenstände der Software entstehen: Analysetätigkeiten (zahlreiche Entwicklungsdokumente) > Programmierung (Quellcode) > im Betrieb (Maschinencode oder ausführbarer Code). Im engeren Sinn der Ausführung auf dem Computer gilt lediglich Letzteres als ‚Software‘. Siehe auch Softwareentwicklung.
• • In diesem Zusammenhang ist Software Bearbeitungsgegenstand von Systemprogrammen: Wenn z. B. ein Compiler den Quellcode eines Programms liest, verarbeitet und einen Maschinen- oder Zwischencode erzeugt, so sind das aus dessen Sicht ‚Daten‘.
• • Einmal erzeugte Software kann mit verhältnismäßig geringen Kosten vervielfältigt werden, die meist durch Datenträger, Werbung und dem Herstellen von Verpackung und zu Papier gebrachten Dokumentationen anfallen.
• • Software verschleißt nicht durch Nutzung, unterliegt jedoch mit der Zeit der Softwarealterung.
• • Software ist meist austauschbar, fähig zur Aktualisierung, korrigierbar und erweiterbar, insbesondere dann, wenn bestehende Richtlinien eingehalten werden und der Quelltext verfügbar ist.
• • Software tendiert dazu, umso mehr Fehler zu enthalten, je komplexer sie ist.^[22] Fehler werden in aktualisierten Softwareversionen oder mithilfe eines Patches und i. d. R. nach Durchführung von Softwaretests behoben. Softwarefehler bezeichnet man auch als Programmfehler oder als „Bugs“.
• • Weil Software unter Einsatz vieler unterschiedlicher Programmiersprachen und in vielen unterschiedlichen Betriebssystemen und Systemumgebungen entwickelt werden kann, sind Softwarestandards erforderlich, um Informationen system- und unternehmensübergreifend ,verstehbar‘ und austauschbar zu machen. Siehe auch Elektronischer Datenaustausch (Beispiele), Programmierstil.

As a rule, the software is adapted and expanded several times after development. The software lifecycle can be several years.

• • Software is developed using certain procedures, methods and "tools". Different development stages are run through, in which different intermediate versions of the software arise: Analysis activities (numerous development documents)> Programming (source code)> in operation (machine code or executable code). In the narrower sense of execution on the computer, only the latter is considered 'software'. See also software development.
• • In this context, software is the processing object of system programs: For example, if a compiler reads the source code of a program, processes it and generates machine or intermediate code, this is 'data' from its point of view.
• • Once software has been created, it can be reproduced at relatively low costs, which are usually incurred through data carriers, advertising and the production of packaging and documentation put down on paper.
• • Software does not wear out due to use, but is subject to software aging over time.
• • Software is mostly interchangeable, capable of updating, correctable and expandable, especially if existing guidelines are complied with and the source text is available.
• • Software tends to contain more errors the more complex it is. ^[22] Errors are corrected in updated software versions or using a patch and usually after software tests have been carried out. Software errors are also known as program errors or "bugs".
• • Because software can be developed using many different programming languages and in many different operating systems and system environments, software standards are required to make information cross-system and cross-company, understandable and interchangeable. See also electronic data exchange (examples), programming style.

Selection of software

In the decision to purchase software, i. W. differentiate between the use of standard software or our own production (individual software). This decision often results in high costs, especially in the business environment. Such decisions can also be the basis for implementing the corporate strategy or should significantly improve corporate processes. To avoid bad investments, the purchase should be preceded by a systematic decision-making process.

• • Der Einsatz von Software erfordert je nach Einsatzbereich ein gewisses Maß an Organisation, um die zusammengehörenden Teile richtig einzusetzen und durch neue Versionen abzulösen (zum Beispiel in größeren Unternehmen im Releasemanagement).
• • Mitunter kann Software vorkonfiguriert werden, um so eine Neuinstallation zu beschleunigen und um Fehler bei der Konfiguration zu minimieren.

Operation of software

• • Depending on the area of application, the use of software requires a certain degree of organization in order to correctly use the parts that belong together and replace them with new versions (for example, in larger companies in release management).
• • Sometimes software can be pre-configured to accelerate a new installation and to minimize configuration errors.

Software from the perspective of business management and work sociology

Applied essentially for business application software, software can be viewed from a (business) economic perspective as 'intellectual work done in advance', i.e. as an investment. For example, the program authors develop a solution for the correct separation of all German words in a word processing program. This means that the intellectual work "correct separation of German words" is done in advance, before this activity actually occurs, for all writers who work with this word processing program. The ability of computers to perform tasks that are transferred to them is used much faster and more reliably than was previously possible for humans. Especially in software development, algorithms and parts of code developed “in advance” are used intensively - as parts of a program (“software reuse”).

A similar connection is seen in the sociology of work: Such software-based measures are suitable for significantly changing work content and work processes. The spectrum ranges from the provision of simple tools (e.g. for summation or averaging) to the complete redesign of processes (by concentrating previously separated or by disassembling earlier centralized work processes) - or even completely replacing them with IT solutions. Brödner and others call this "materialized" brain work. ^[23] See also rationalization, optimization, Taylorism.

Categorization of software

• • Systemsoftware: Anwendungsunabhängige Software, die das Ausführen von Anwendungssoftware ermöglichen bzw. unterstützen (z. B. Betriebssystem, sowie Gerätetreiber und Dienstprogramme)
• • Unterstützungssoftware, d. h. Programme, die bei der Entwicklung, Wartung helfen oder eine nicht-anwendungsspezifische Leistung erbringen (z. B. Editoren, Compiler, Virenscanner, Datenbankmanagementsysteme, ...)
• • Anwendungssoftware, die den Benutzer bei der Ausführung seiner Aufgaben unterstützt und ihm dadurch erst den eigentlichen, unmittelbaren Nutzen stiftet (z. B. eine Tabellenkalkulation)

According to ISO / IEC 2382, software is structured (and labeled) as follows: ^{[24] [25]}

• • System software: application-independent software that enables or supports the execution of application software (eg operating system, device drivers and utilities)
• • Support software, ie programs that help with development, maintenance or perform a non-application-specific service (e.g. editors, compilers, virus scanners, database management systems, ...)
• • Application software that supports the user in the execution of his tasks and thereby provides him with the actual, immediate benefit (eg a spreadsheet)

• • Standardsoftware wird von einem Softwareanbieter zum Einsatz bei mehreren/vielen Kunden erstellt, die diese Software erwerben können.
• • Individualsoftware wird für einen einzelnen Anwender zur Lösung einer spezifischen Aufgabenstellung individuell erstellt oder modifiziert, alternativ durch einen Softwareanbieter oder durch eigene Entwickler bzw. Entwicklungsabteilungen eines Unternehmens.

Subdivision according to the degree of individuality

• • Standard software is created by a software provider for use with several / many customers who can purchase this software.
• • Individual software is created or modified individually for a single user to solve a specific task, alternatively by a software provider or by a company's own developers or development departments.

Legally, when purchasing software, a distinction is made between individual software and standard software: For individual software, a work contract or work delivery contract is concluded, the purchase of standard software is considered a property purchase.

Subdivision according to the type of results generated

• • Quellcode, Zwischencode, Maschinencode, Gerätetreiber und andere erforderliche Module (als Programmbibliothek ausgeliefert)
• • Installationsprogramme und dazugehörende Anweisungen
• • Weitere Unterlagen wie die Dokumentation für Softwareentwickler und Softwarebenutzer

These arise in the course of the software manufacturing process and can be, for example:

• • Source code, intermediate code, machine code, device drivers and other required modules (supplied as a program library)
• • Installers and associated instructions
• • Other documents such as documentation for software developers and software users

Software based on the type of embedding

• • Non-embedded software that is installed afterwards
• • Software permanently installed in a device to control it (eg in a ROM or as part of an embedded system) is referred to as firmware or also as embedded (or, embedded ') software

• • Adware
• • Beerware
• • Cardware (auch Postcardware)
• • Careware
• • Crippleware
• • Donationware
• • Freeware
• • Nagware
• • Shareware
• • Freie Software

Classification according to right of use (license)

• • adware
• • Beerware
• • Cardware (also postcardware)
• • Careware
• • Crippleware
• • Donationware
• • Freeware
• Nagware
• • Shareware
• • Free software

• • Freie Software
• • Open Source
• • Proprietäre Software

Subdivision according to source code availability

• • Free software
• • Open source
• • Proprietary software

• • Abandonware
• • Vaporware

Classification based on availability

• • Abandonware
• • Vaporware

• • Portable Software: Auf verschiedenen Computer(typen) lauffähig
• • Native Software: Zur Ausführung auf einem bestimmten Computersystem erstellt oder kompiliert. Der Programmcode nutzt die individuelle Funktionalität eines bestimmten Systemtyps, Allgemeingültigkeit und Portabilität gelten nicht als Entwicklungsziel.^[26]
• • Bananenware (unausgereifte Software)
• • Schlangenöl (Programm ohne echte Funktion, wird aber als Wundermittel angepriesen)
• • Shovelware (Sammlung von Software, wobei die Quantität zählt)
• • Riskware
• • Bloatware (mit Funktionen ohne synergetischen Nutzen überladene Software)
• • Spyware
• • Gebraucht-Software

More software terms

• • Portable software: Runs on different computers (types)
• • Native software: created or compiled to run on a specific computer system. The program code uses the individual functionality of a certain system type, general validity and portability are not considered as development goals. ^[26]
• • Banana ware (immature software)
• • snake oil (program without real function, but is touted as a miracle cure)
• • Shovelware (collection of software, where quantity counts)
• • Riskware
• • Bloatware (software overloaded with functions without synergetic benefits)
• • spyware
• • Used software

Licensing models

• Verkauf Der vollständige Verkauf von Software, inklusive der Überlassung von Weiterverbreitungsrechten, kommt praktisch nur zwischen Unternehmen vor, in der Regel im Rahmen von Auftragsprogrammierung oder beim Verkauf eines Softwareentwicklungsunternehmens.
• Nutzungsrecht Bei der meisten Software, die zum Beispiel für PCs „gekauft“ werden kann, wird in Wirklichkeit nur ein Nutzungsrecht überlassen. Dieses Modell ist auch bei der Auftragsprogrammierung üblich, bei der ein Unternehmen ein Programm für den Eigengebrauch eines anderen Unternehmens speziell entwickelt. Bei Freeware ist dieses Recht kostenlos, was nicht mit freier Software verwechselt werden darf.
• Software as a Service Die Software wird bei einem Dienstleister gehostet, die eigentliche Nutzung der Software kann entweder pro Zeitraum oder pro Nutzungseinheit berechnet werden. sie findet oft auf einem einfachen PC und z. B. per Webbrowser statt.
• Freie Software/Open Source/GPL Freie Software darf von jedem genutzt, beliebig verändert und weiterverbreitet werden. Oft unterliegt dieses Recht gewissen Einschränkungen, wie zum Beispiel der Nennung des Autors oder die Verpflichtung, veränderte Versionen unter die gleiche Lizenz zu stellen (GPL). Software, die nicht zu dieser Gruppe zählt, wird proprietär genannt.

The distribution and use of software is subject to copyright. In this context, there are several typical leasing models:

• Sales The complete sale of software, including the granting of redistribution rights, occurs practically only between companies, usually as part of order programming or when selling a software development company.
• Right of use With most software that can be "bought" for PCs, for example, only one right of use is actually granted. This model is also common in job programming, where one company specifically develops a program for another company's own use. With freeware, this right is free, which should not be confused with free software.
• Software as a service The software is hosted by a service provider, the actual use of the software can be calculated either per period or per unit of use. it often takes place on a simple PC and e.g. B. instead of a web browser.
• Free software / open source / GPL Free software may be used by anyone, modified as desired and distributed. This right is often subject to certain restrictions, such as naming the author or the obligation to place modified versions under the same license (GPL). Software that does not belong to this group is called proprietary.

There are numerous intermediate and mixing stages between the above main forms of software distribution.

See also: Free Software Licenses and License Management

Free software and open source
→ Main article: Free software and open source

'Free software' is a social movement that sees non-free software as a social problem. ^[27] Whereby "free" here does not mean "free"("FreeSoftware" is not the same as "Freeware"), but means the freedoms for society that such a licensed (also commercial) product offers. In the eyes of the Free Software Foundation (FSF) founded by Richard Stallman in 1985, the decision for or against free software is therefore primarily an ethical and social decision.

In contrast, the Open Source Initiative (OSI), founded in 1998, sees open source software as a mere development model, whereby the question of whether software should be open source is a purely practical and not an ethical question. The FSF therefore accuses the OSI of a distraction from the essential points. ^[28] Eric S. Raymond introduced the term 'open source' on the assumption that the unpopular issue of 'freedom' could deter funders for such projects.

Even if today there are two different movements with different views and goals, they share a common appreciation for open-source code, which results in numerous projects in which they work together.

Application software

Computer software that is used to process or support a useful or desired non-system-technical functionality is referred to as application software. ^[1] They serve the "solution to user problems". ^[2] Examples of areas of application are: image processing, email programs, web browsers, word processing, spreadsheets or computer games.

From the English term application, the term application, or app for short, has also become commonplace in everyday language. Since the appearance of the iOS App Store (2008), the abbreviation app has been almost exclusively equated with the mobile app in German-speaking countries, i.e. application software for mobile devices such as smartphones and tablet computers. However, desktop application software is now also sometimes referred to as an app, for example in Microsoft's Windows operating system since Windows 8 (Windows apps), which is used on both desktop PCs and tablets, or in Apple's macOS operating system with the Mac App Store. ^[3]

In companies

Application software is used to a large extent to support administration in authorities and companies. Application software is partly standard software, mostly industry solutions tailored to the respective application are used as individual software. In the area of strategic and economic application software within a company (such as enterprise resource planning systems or portal software), one also speaks of business applications, business software or company software.

On mobile devices
→ Main article: Mobile app

Mobile apps can be obtained from an app store integrated into the mobile operating system and installed directly on the device. Mobile web apps are accessed via the mobile device's web browser and do not need to be installed.

In web browsers
→ Main article: web application

Web applications are a special form of application software. These are accessed from the workstation or mobile device via a web browser and run in the browser. In contrast to desktop applications, web applications do not require a special operating system, but sometimes special runtime environments.

Differentiation from system-related software

Application software (according to ISO / IEC 2382) is in contrast to system software and utilities. This includes “the programs that are necessary for the correct operation of a computer system, as well as all programs that support program creation, eg. B. Provide translators and test tools and general services [... formatting, file management, data transfer ...] “, ^[2] but which do not bring any end-user-related 'benefit'. Examples are the operating system, compilers for different programming languages or database systems.

Application software can either be installed locally on a desktop computer (desktop application) or on a mobile device or run on a server which is accessed by the desktop computer or mobile device (client-server or web application). Depending on the technical implementation, it can be executed in batch processing mode or in dialog mode (with direct user interaction). However, these two distinctions apply to all computer programs, in principle also to system software.

Mobile app

As a mobile app (in German mostly in short form the app [εp], an abbreviation for the technical term application; sometimes also the app ^[1] ; in English [aep] as a short form for English application) is an application software for mobile devices Operating systems called. Although the term app refers to any type of application software, it is often equated with application software for smartphones and tablets in the German-speaking world. Mobile apps differentiate between native apps that only work on one platform and platform-independent web, hybrid and cross-platform apps.

They are available for a wide variety of areas, from the simplest utilities and fun applications with just one function to program packages with extensive functionality. For example, office applications, games, guides, fitness apps, for emulating older home computers and programmable calculators, as an aid for diabetics and much more. With the help of mobile remote apps, digital devices such as cameras, action camcorders or quadrocopters are increasingly being controlled remotely. The majority of these apps are free of charge, a smaller part has to be bought in the respective app store for mostly small amounts ^[2]

With web browsers such as B. the Dolphin Browser, surfing the Internet on a mobile device is possible

Even the first cell phones often contained small applications such as calendars, calculators or small games. These were designed by the manufacturer for the respective operating system, permanently installed and can only be deleted with root rights. With the appearance of Java on mobile phones (Java ME), users were able to download simple applications and games from their mobile network operator or from the Internet via WAP (MIDlets), which were often platform-independent. A hobby programmer scene developed, but also professional software houses offered such applications for a fee. Applications could also be installed on various PDAs. The predecessors of smartphone apps are the Palm OS PDA applications, which usually consist of only one file and can be used directly after the transfer. Programs could be created on Psion organizers with the device itself.

For mobile phones with their own operating system and the option of installing corresponding apps, the term smartphone prevailed around the year 2000 ^[3] . This term was first used by Ericsson in the mobile area for the prototype GS88. At the same time, the Communicator series from Nokia, on whose later models the Symbian operating system ran, became widespread. In 2002, the Siemens S55 and Nokia 7650 were among the first smartphones available on the mass market, on which Java programs could be transferred and executed manually. Only with the appearance of the Apple iPhone 2007 and later the Android mobile phones and other smartphones did the possibility of installing applications on mobile devices become more common among broad sections of the population, supported by correspondingly increased marketing by the manufacturers. ^[4] On most smartphones, some apps, such as a web browser, an email program and a calendar, are already preinstalled. In June 2016, over two million apps were offered for iOS alone. ^[5]

Over 90 billion apps were downloaded worldwide in 2016 (iOS app store and Google play store). In Germany, sales increased 40 percent year over year to $ 750 million. On average, an Android smartphone user spent more than 1.5 hours a day in apps. The list of the most popular apps (most downloads) in Germany tops WhatsApp in 2016, followed by Facebook Messenger and Facebook App. Snapchat ranks fourth, followed by Instagram. The top-selling apps were Lovoo, Spotify and Tinder. ^[6]

Native apps

• • Java und Kotlin für Googles Android
• • Objective-C und Swift für Apples iOS
• • C#, C und C++ für Microsofts Windows

Native apps are characterized by the fact that they are specially adapted to the target platform. Since a native app uses the programming interfaces (APIs) of the target platform directly, the range of applications is very high. In addition, all platform-specific hardware and software functions can be accessed, such as files, GPS, acceleration sensors, microphone and camera. Due to the various software platforms, however, it is not possible to install an Android app on an iPhone, for example, or vice versa. A software company must therefore develop the application for each end device individually. Each mobile platform has its own software development kit (SDK) and its own integrated development environment (e.g. Android Studio or Xcode), which can be used by developers. The preferred programming languages for the largest systems are:

• • Java and Kotlin for Google's Android
• • Objective-C and Swift for Apple's iOS
• • C #, C and C ++ for Microsoft's Windows

With native apps, the most diverse types of devices can be operated at once, if all are based on one platform. The Universal Windows Platform makes it possible to write native Windows apps for desktop PCs, laptops, tablets, smartphones and Xbox One at once. ^[7]

Platform independent apps

See also: Platform independence

The rapid development of different operating systems, such as Android, Windows, iOS and mobile devices, from smartphones to tablets to notebooks and smart TVs, is causing companies to rethink. According to a study by the market research institute GfK, more than 60% of adults in the US use at least two devices a day and around 25% use at least three devices. ^{[8] It is} therefore important that the app is available on all different devices and works without any problems. ^[9] This expectation has increased the need for cross-platform hybrid and cross-platform applications.

Platform-independent apps are becoming increasingly important, especially in companies that need different devices. The phenomenon of bring your own device (abbreviation: BYOD, in German: "Bring your own device with you") in particular means that companies are faced with the task of providing in-house programs and applications for all operating systems and device types. Mobility and flexibility also play a major role. An application that runs on desktop computers is said to B. also work with the external customer visit on the tablet or on the go on the smartphone. It tries to develop for several platforms at the same time as simply as possible. To do this, Google ported large parts of the source code from Inbox from Java to Objective-C using the "J2ObjC" software. ^[10] Microsoft also offers the "Windows Bridge" a way to develop Windows apps with iOS APIs. ^[11]

Web apps

Web apps (e.g. office programs) can be called up with a web browser. Google Docs here.

See also: web application and progressive web app

Mobile web apps are accessed via the web browser of the mobile device and do not require any installation. They use web standards such as HTML5 or JavaScript so that they can be operated on any device. In contrast to mobile apps, which have to be newly implemented for each platform, an implementation of web apps can be used on many different platforms. Ideally, a mobile web app behaves exactly like a native app, so it is not perceived by the user as a website, but instead offers a user interface that is optically and ergonomically integrated into the mobile device. Disadvantages of web apps are that they cannot access all hardware components and that the available data transfer speed plays an important role. A slow internet connection (for example due to poor network reception) can lead to noticeable delays in interactivity.

When using web apps, more data usually has to be transferred than when using a native app. Thus, higher transmission fees (especially roaming fees abroad) for the resulting data traffic can be an obstacle for many users. B. to use on vacation. The temporary storage of the required data in a local memory (cache) is a practical way out so that it can also be made available offline. However, the amount of data to be stored in the device using web storage technology is usually very limited. ^[12]

Unlike all other types of mobile apps, mobile web apps cannot be offered in app stores.

Hybrid apps

Hybrid apps are a special form of a mobile app. They combine the advantages of native and web apps by accessing many hardware and software components of the mobile device and at the same time being able to operate different platforms. They can run on different mobile devices (smartphone & tablet) and PCs as well as on different operating systems.

Hybrid apps combine the advantages of native apps and web applications in that source code can be used across platforms. ^[13] The code is written in web technologies such as HTML, CSS and JavaScript. ^[14] Hybrid apps run - not visible to the user - within the native web browser the respective platform, e.g. B. Safari or Google Chrome. ^[15] The framework used suppresses all control elements of the browser, such as the menu bar with URL or bookmark bar.

Various frameworks are available for the development of hybrid apps. One of the largest development platforms is Cordova from the Apache Software Foundation and the PhoneGap from Adobe based on it. ^[16] There are other companies such as Ansca Mobile with the Corona SDK and Drifty with lonic solutions for developing hybrid apps. There are various development environments, such as Microsoft's Visual Studio, that support the development of hybrid apps.

The framework loads a library that establishes communication between JavaScript and the respective operating system-specific language. This enables hybrid apps to access various hardware and software components of the mobile device. Access is possible, among other things, to contacts, camera, motion sensor, GPS and files. Modern render engines increase the calculation speed of the interpretation of the HTML5, CSS3 and JavaScript code. This allows the execution speed to be increased many times over. ^[17] Technology such as WebGL accelerates complex 3D graphics without additional hardware extensions.

A major advantage of the hybrid apps is that one development can cover many platforms and there is no need for more expensive parallel developments for the respective ecosystems. As a result, the development effort on the part of the software company drops considerably, which means that the user interface and functionality can be kept at the same level across multiple platforms. However, not all device or operating system-specific properties can be used and when implementing the hybrid app, platform-specific interaction designs and the look and feel of the respective platform can only be taken into account to a limited extent. In addition, much slower loading times and much poorer computing power, for example in complex games, are possible because they act with the intermediate layer of the web browser.

Cross platform apps

Similar to a hybrid app, a cross-platform app is an application that can be run on different operating systems and devices, regardless of the platform. In contrast to the hybrid app, the user interface is usually built with the native APIs of the respective operating system and is not displayed in a web browser. ^[18] This means that up to 75% of the source code can be shared between the various platforms without significantly reducing performance. ^[19] The source code is mostly written in C #, C ++ or JavaScript.

Frameworks for cross-platform development are the "Xamarin platform" from Xamarin, Appcelerators "Titanium Mobile" and React Native from Facebook. All three frameworks support the development of cross-platform apps for Android, iOS and Windows. With “Xamarin.Forms”, large parts of the user interface code can also be shared between the platforms. The cross-platform placeholder control element is converted into a native control element at runtime. ^[20]

Google's Flutter SDK enables the development of cross-platform apps for iOS and Android in the Dart programming language. Flutter does not use native controls, but rather draws with its own rendering engine. ^[21]

However, model layer code in C ++ can also be shared between these platforms without the need to use a framework. ^[22]

development

See also: programming

When developing mobile apps, some restrictions have to be observed compared to applications for desktop computers. B. the processors of smartphones are less powerful and run on battery power. There is also a large number of different screen sizes, hardware configurations and software versions. Mobile apps are mostly developed with the help of an integrated development environment and the software development kit of the corresponding platform. The software can be tested with an emulator before trying it out on real devices.

Many developers now rely on voice dialog systems, in contrast to "normal" mobile user interfaces. ^[23] These can either be in the form of speech recognition, such as. B. with Siri, or in the form of chatbots, e.g. B. in Skype or Facebook Messenger. ^{[24] [25]} This form of interaction with applications is growing because many users are overwhelmed by the multitude of apps. ^[26] Microsoft's CEO Satya Nadella sees chatbots "as the next big thing", which will bring as far-reaching changes as before to the iPhone for touchscreens or the use of graphical user interfaces. ^[27]

The employment area for software developers of apps for mobile platforms continues to grow, until 2012, according to a report by "TechNet", alone in the USA 466,000 created new jobs. ^[28] In Europe, according to a report by the Progressive Policy Institute, there will be 1.64 million jobs in early 2016 that depend on mobile apps. ^[29] The manufacturers of mobile operating systems try various methods to win software developers for their platform. In October 2016, Apple plans to open an “iOS App Development Center” in Naples, Italy, in which developers are trained. ^{[30] [31]} Google wants to train two million developers in India and offers various courses in the field of Android development through Udacity. ^{[32] [33]}

distribution

Apps can usually be obtained from an Internet sales platform integrated into the operating system and installed directly on the device. As a result of the great market success of smartphones and tablets, practically all manufacturers of mobile operating systems have developed their own platforms in order to market the apps developed for their respective devices. Customers can download the apps there free of charge or for a fee. The sales platform with the largest number of programs is the Google Play Store for Android devices, ^[34] followed by the App Store for iOS. There are also separate app stores for devices with other operating systems. Most of the proceeds go to the developers, and the operator of the sales portal also participates in the profits. Apple, Google and Microsoft retain 30 percent of the purchase price of an app as a commission. As a rule, apps are technically checked by the portal operator, and in some cases there is an additional content check.

There are basically different ways of getting an app to a device: directly via the mobile internet connection or WiFi of the device or with the help of a PC, which can be used to install apps when the mobile device is connected using appropriate software (such as iTunes). Some app platforms also make it possible to buy the app on the PC and automatically install it on all synchronized devices, with the app being downloaded automatically from the devices. ^[35] Provided that the manufacturers keep their mobile operating system accessible for external sources for the installation of application software, there are also other, often cross-platform offers through shops from different providers on the Internet, as well as the possibility of direct reference to the websites of the app developers.

privacy

Many mobile apps are criticized by consumer advocates because, without the knowledge of the user or their consent, they send data that is not necessary for the app to function or that is unencrypted or not anonymized and can therefore be easily spied on. The operators of platforms on the Internet, such as social networks or shopping portals, are enabled with apps to collect data and use it for targeted and efficient advertising purposes or to pass it on to third parties. ^[36] It is particularly critical if, for example, sensitive personal data such as account details or credit card information can be spied on in shopping apps. ^[37] Many apps also collect data via automated analytics services such as Google Analytics or Twitters Fabric. ^[38]

Like all other programs, native apps can contain security holes. It is therefore essential to ensure updates to the end device and software maintenance by the provider. Native apps run as an independent program on the respective device and thus have expanded access to resources. This problem is countered by using a sandbox, which limits access to program interfaces provided by the manufacturer and can therefore be regulated. ^{[39] [40]}

Use in companies

Mobile apps are used in companies in various areas. Applications that are used in the company by the employees on PCs are used. B. Enterprise Resource Planning (ERP), Customer Relationship Management (CRM) or Microsoft Outlook, also on mobile devices available so that you can work anywhere. Another area of application is marketing. Apps are used there, for example, to support sales staff, for example by providing internal product catalogs or spare parts lists with direct online ordering options, also in connection with the previous query of inventory levels and / or forecasts of the current delivery time of a product.

safety
→ Main article: Mobile device management

Mobile apps often pose a high security risk for companies in the bring-your-own-device context, because they sometimes transmit sensitive data without the knowledge and consent of users. This not only means the loss of confidential information, but also makes companies vulnerable and blackmailable. ^[41] In corporate use, so-called mobile device management systems ensure that desired apps can be distributed centrally to the devices, in part through a dedicated reference portal. In the case of pure company smartphones or tablets, the installation of other apps is technically often prevented by the user for security reasons, since otherwise a possible point of attack for industrial espionage and other risks from malware would be created. So-called persona can be used to separate the respective data and applications for the clean separation of apps on corporate mobile devices with partial private use. ^[42]

Unless internal IT and security guidelines are not used in company use, the conventional sales channel via an app store is generally out of the question, because it would also make the company's - often self-developed - mobile apps accessible to the public. Instead, such apps are made available to the user centrally by a system administrator of the company via mobile device management solutions or automatically installed on the smartphone. ^[43]

App wrapping

One option for securing company data is app wrapping. With app wrapping, company-relevant applications are encrypted in another app. This ensures that only safe and approved applications are used in the company. ^[44] However, this also has disadvantages, it can lead to copyright infringements and even loss of warranty rights. ^[45]

Native app management

Alternatively, there is the option of offering native apps securely through mobile device management without affecting the native user experience. ^[46] This function has been offered by Apple since iOS 7, Google with "Android for Work" and Samsung with Knox. ^{[47] [48]}

Internet

The Internet (from the English internetwork, composed of the prefix inter and network, network 'or net' for short, network '), colloquially also the network, is a worldwide network of computer networks, the autonomous systems. It enables the use of Internet services such as WWW, email, Telnet, SSH, XMPP, MQTT and FTP. Each computer can connect to any other computer. The data exchange between the computers connected via the Internet takes place via the technically standardized Internet protocols. The technology of the Internet is described by the RFCs of the Internet Engineering Task Force (IETF).

The spread of the Internet has led to extensive upheavals in many areas of life. It contributed to a modernization push in many economic sectors as well as the emergence of new branches of industry and has led to a fundamental change in communication behavior and media use in the professional and private spheres. The cultural significance of this development is sometimes equated with the invention of book printing.

The transmission of data on the Internet regardless of its content, the sender and the recipient is referred to as network neutrality.

Infrastructure

• • Providernetzwerke, an die die Rechner der Kunden eines Internetproviders angeschlossen sind,
• • Firmennetzwerke (Intranets), die die Computer einer Firma verbinden, sowie
• • Universitäts- und Forschungsnetzwerke.

The Internet consists of networks of different administrative administrations that are interconnected. Among them are mainly

• Provider networks to which the computers of the customers of an Internet provider are connected,
• • Company networks (intranets) that connect a company's computers, as well as
• • University and research networks.

Physically, the Internet in the core area, i.e. with connections between the above-mentioned networks and in the backbones of large networks, consists mainly of fiber optic cables, continental and intercontinental, which are connected to a network by routers. Fiber optic cables offer enormous transmission capacity and were laid a number of years ago both as land and sea cables in anticipation of very high data traffic growth. However, since the physically possible transmission rate per fiber pair has increased immensely with advanced light feed technology (DWDM), the Internet currently has overcapacity in some cases. In 2005, it was estimated that only three percent of the glass fiber laid between European or US cities was used. ^[17] Satellites and microwave links are also integrated into the global Internet structure, but have a small share.

On the so-called last mile, i.e. the house connections, the data is often transmitted on copper lines from telephone or television connections and increasingly also via radio, using WLAN or UMTS. Glass fibers up to the house (FTTH) are not yet very widespread in Germany. Private individuals access the Internet either via a narrowband connection, for example via modem or ISDN (see also Internet by Call), or via broadband access, for example with DSL, cable modem or UMTS, from an Internet provider. Companies or government institutions are often connected to the Internet via dedicated lines based on copper or fiber optics, whereby technologies such as channel bundling, ATM, SDH or - more and more frequently - Ethernet are used in all speed variants.

In private households, computers for accessing services are often connected to the Internet which themselves provide few or no such services for other subscribers and are not permanently accessible. Such computers are referred to as client computers. Servers, on the other hand, are computers that primarily offer Internet services. They are usually located in so-called data centers, are quickly connected to them and are secured in air-conditioned rooms against power and network failure as well as burglary and fire. Peer-to-peer applications also enable the above client computers to temporarily offer themselves services that they call up from other computers in this network. In this way, the strict distinction between the client-server model is resolved.

Many different backbone networks are connected to one another at Internet nodes via powerful connections and devices (routers and switches). The exchange of accessibility information between two networks is then contractually and technically organized as peering, i.e. on the basis of reciprocity, and data exchange is thus made possible. At DE-CIX in Frankfurt am Main, the largest exchange of this kind, more than a hundred networks are interconnected. Such a transfer of data traffic between separate administrative areas, so-called autonomous systems, can also be switched to any other location, but it is usually economically more sensible to do this in a bundled manner at different Internet nodes. Since an autonomous system, such as an Internet provider, cannot usually reach all others in this way, it itself requires at least one provider to deliver the remaining data traffic for a fee. This process is technically similar to peering, only the so-called upstream or transit provider provides the customer provider with all accessibility information available via the Internet, including those for which he himself has to pay for the delivery of the data traffic leading to them. There are currently nine very large, so-called Tier 1 providers that can process all of their data traffic reciprocally or deliver it to their customers without the need for an upstream provider.

Since the Arpanet as a decentralized network should be as fail-safe as possible, care was taken during the planning stage that there should not be a central computer, i.e. no location where all connections converge. However, this decentralization was not observed at the political level of the Internet. The Internet Corporation for Assigned Names and Numbers (ICANN), as the highest hierarchical organization, is responsible for the assignment of IP address ranges, the coordination of the Domain Name System (DNS) and the necessary root name server infrastructure as well as for the definition of other parameters of the Internet protocol family that require worldwide uniqueness. It is formally subordinate to the US Department of Commerce. ^[18]

The network-like structure and the heterogeneity of the Internet contribute to a high level of reliability. For the communication between two users, there are usually several possible routes via routers with different operating systems, and it is only when the actual data transmission is decided which one is used. Two data packets sent in succession or an inquiry and the response can run through different paths depending on the load and availability. Therefore, the failure of a physical connection in the core area of the Internet usually has no serious effects; only a failure of the only connection on the last mile cannot be compensated.

Internet protocol and domain name system

The Internet is based on the Internet protocol family, which regulates the addressing and data exchange between different computers and networks in the form of open standards. The protocol in which the globally unique addressing of connected computers is defined and used is called Internet Protocol (IP). Communication with it is not connection-oriented, as with the telephone, but rather packet-oriented. This means that the data to be transmitted are transmitted in IP packets with a size of up to approx. 65,000 bytes, but mostly only 1500 bytes, which each contain IP addresses as send and destination information. The recipient reassembles the data from the package contents, also called user data, in a specified order.

Depending on the task, the network protocols are assigned to different layers, with protocols of a higher layer including user data being transported in the user data of lower layers. The standards and protocols of the Internet are described and defined in RFCs. A great advantage of the Internet protocol is that packet transmission can take place regardless of the choice of operating systems used and regardless of the network technology of the protocol layers below IP, similar to how an ISO container can be transported one after the other by freight, rail and truck to get to his destination.

In order to be able to address a specific computer, the Internet protocol identifies it with a unique IP address. Version IPv4 is four bytes (32 bits), which are specified as four decimal numbers in the range from 0 to 255 separated by a period, for example 66.230.200.100. In the new version IPv6, these are 16 bytes (128 bits), which are specified as eight blocks separated by colons, each consisting of four hexadecimal digits, e.g. B. 2001: 0db8: 85a3: 08d3: 1319: 8a2e: 0370: 7344. You can think of these addresses as phone numbers for computers with the Domain Name System (DNS) as an automatic phone book.

The DNS is an important part of the internet infrastructure. It is a hierarchically structured database that is distributed over many administrative areas and provides a translation mechanism: A domain name that can be easily recognized by humans (for example “wikipedia.de”) can be translated into an IP address and vice versa. This happens - unnoticed by the user - whenever he clicks on a new hyperlink in the web browser or directly enters a web address. The browser then first uses an IP packet to ask a DNS server known to it for the IP address of the foreign name and then exchanges IP packets with this address in order to access the content of the services offered there, such as websites. To determine the IP address, the DNS server itself often queries other DNS servers in accordance with the hierarchy. The root name server forms the root of the hierarchy, which can be recognized in the names by the dots. In this way, it is possible to achieve the services mentioned with IP packets, through which users only benefit from the Internet. The DNS itself is actually such a service, albeit a very basic one, without which users would have to enter IP addresses instead of names to connect to other computers.

At the core of the Internet, the IP packets have to go through an extensive network. The branches are routers that decide on the shortest route to the destination IP address of the packet. You use routing tables that are automatically created and kept up-to-date via routing protocols; this will automatically react to failed connections. In routing tables, several possible destination IP addresses are grouped together with the help of netmasks - in IPv6 one speaks of prefix lengths - to destination networks, and these are each an output of the router, for example in the form of the jump address to the next router (Next Hop IP Address) assigned for forwarding. The exchange of this accessibility information between autonomous systems takes place exclusively via the Border Gateway Protocol. Many other routing protocols are available within an autonomous system. For computers and routers that are not in the core area of the Internet, a static routing table that is not generated by routing protocols is sufficient. This then contains a default route, often also a standard or default gateway named, which points towards the core area of the Internet for all destination networks, which are not entered otherwise, similar to a signpost "All directions" in road traffic. The routers in the core area currently manage routing tables with up to 540,000 target networks for IPv4 and 21,000 for IPv6. ^[19]

Depending on the service used, higher-level protocols (such as TCP or UDP) are still transmitted in the user data of the Internet protocol, just as an ISO container in freight transport can contain postal packets, in which goods are packed. Most websites use the Hypertext Transfer Protocol (HTTP) based on TCP and the Hypertext Transfer Protocol Secure (HTTPS) for encrypted pages. Emails use the Simple Mail Transfer Protocol (SMTP), also based on TCP, the DNS, however, is largely handled using UDP.

With IPv4, many workstations in the network of a company or organization often receive private IP addresses that are translated to a few public, globally unique IP addresses when communicating externally using Network Address Translation (NAT). These computers cannot be accessed directly from the Internet, which is usually desirable for security reasons (see also: Firewall), but also has obvious disadvantages. There are considerably more public addresses available for IPv6, so according to RFC 4864 NAT can be dispensed with and filtering data traffic has more options.

Data volume

In 2012, the data volume on the permanently wired, publicly accessible Internet was more than 26.7 exabytes (1 exabyte = 1 billion gigabytes) per month, which corresponds to a daily data volume of approximately one exabyte. The data volume of one exabyte is comparable to the more than 2500 times the data volume of all books that have ever been written. ^[24] The volume of mobile data (data exchange via cellular networks) in 2012 was over 1.1 exabytes of data per month.

By 2015, the data volume on the wired internet is expected to grow to approximately 60 exabytes per month. A data volume of more than 6.2 exabytes per month is forecast on the mobile Internet. Video services (video-on-demand) make up over half of the transmitted data. ^[25]

Worldwide, IP data traffic is assumed to be 1.4 zettabytes in 2017; 38 exabytes are assumed in Germany alone, compared to 17 exabytes in 2012. An increase in mobile data traffic with smartphones and tablets is expected to increase by 60% annually to 13.6 exabytes by 2017.

Internet access

Internet access (also Internet connection, Internet connection) generally refers to the communication connection of a computer or a network to the Internet.

A basic distinction is made between broadband data transmission (usually via DSL or cable modem) and conventional narrowband connections via telephone modem or ISDN as well as mobile connections via LTE, HSDPA, UMTS, EDGE or GPRS.

requirements

Internet connections for private subscribers are generally only possible with a service contract with an Internet service provider (ISP) who also offers access services or an Internet access provider (IAP) (even with an Internet-by-call connection) a service contract). The connection is established via a dial-in node or a broadband PoP and a customer-installed modem or ISDN terminal, in the case of wired access, regularly via the subscriber line or the TV cable network.

The end device must also be connected to the individual computer or the local computer network - via cable (LAN, i.e. wired), wireless LAN, Bluetooth (radio) or via the power network. A device driver is also required for the modem. The data throughput of the data exchange is measured at bits per second (bit / s or b / s); in the widespread DSL standard, at least 1024 kbit / s (kilobit / s) are generally transmitted in the download and 128 kbit / s in the upload direction.

A connection can be established via GMDSS, UMTS or other mobile internet or a surf stick. The SIM cards must first be activated for the Internet.

In summary, the following telecommunications connections are conceivable: dial-up, ISDN, DSL variants (ADSL, SDSL, VDSL, PortableDSL, Internet access via satellite), cable modem, WLAN, WiBro, WiMAX, mobile radio (LTE, CSD and HSCSD, GPRS, EDGE , UMTS with HSDPA, WAP), fiber optic network, carrier frequency system (Powerline Communication) and xMax (only in North America).

Use and technology

• • IP-Telefonie und ISDN over IP
• • Internetsurfen (Ansteuern von Dateien, die über Server erreichbar sind, beispielsweise Homepages/Websites/Netzpublikationen, E-Mails (sofern via POP3), Webcam)
• • Datenübertragung zwischen Server und Client, oder dezentral zwischen vielen Clients untereinander, etwa durch FTP oder Peer to Peer
• • IPTV (Fernsehen)
• • Internet Protocol
• • Internetprotokollfamilie
• • WAP und I-mode (jeweils für moderne Mobiltelefone)

Modem (V.34 standard) according to the ISA standard, obsolete since the 1990s

• • IP telephony and ISDN over IP
• • Internet surfing (control of files that are accessible via servers, for example homepages / websites / network publications, e-mails (if via POP3), webcam)
• • Data transmission between server and client, or decentrally between many clients among themselves, for example via FTP or peer to peer
• • IPTV (television)
• Internet Protocol
• • Internet protocol family
• • WAP and I-mode (each for modern mobile phones)

An Internet connection is available from dialing into the ISP network, not necessarily by activating the browser window.

After 24 hours online time, many providers are forced to separate.

Contract law

The provision of the Internet line is generally a service contract in Germany. ^[2] The connection is switched off in Germany according to § 45k Telecommunications Act, not only according to the respective terms and conditions. There are numerous decisions in the case law on this.

World Wide Web

The World Wide Web [, w3: ld waid'wεb] (English for "worldwide network", short Web, WWW, rare and especially in the early days and in the USA also W3) is a system of electronic hypertext that can be called up via the Internet. Documents, so-called websites. They are linked to each other by hyperlinks and are transmitted on the Internet using the HTTP or HTTPS protocols. The websites mostly contain texts, often illustrated with pictures and graphic elements. Videos, audio documents and pieces of music are also often embedded.

General

Colloquially, the World Wide Web is often equated with the Internet, ^[1] however, it is younger and represents only one of several possible uses of the Internet. Other Internet services such as e-mail, IRC or Telnet are not in the World Wide Web integrated.

A web browser is required to access content from the World Wide Web. B. runs on a PC or smartphone. With it, the user can download the data provided on any selected web server and have it displayed on a suitable output device such as a screen or a Braille display. The user can then follow the hyperlinks on the displayed website that refer to other websites, regardless of whether they are stored on the same web server or another. This creates a worldwide network of websites. Tracking the hyperlinks is also referred to as "surfing the Internet".

With the so-called Web 2.0, websites became popular from around the 2000s, the content of which users can not only view passively, such as on news pages, but also change and supplement themselves, e.g. B. to publish your own content or to communicate with other users. These include blogs as private opinion pages, pages created by a loose community of authors based on the wiki principle and social networks. Server-side techniques and (scripting) languages that implement this interactivity are primarily CGI, Python, ASP, Apache Wicket, JSF, ColdFusion, Ruby and SSI. To client-side techniques that e.g. B. individualize the content using filters include CSS, JavaScript or Java, whereby Java is mainly used for the platform-neutral execution of programs that are often loaded as web applications via the Internet and with Internet-based databases (e.g. SAP clients) communicate. With the interactivity, the use of search engines became possible, which supplemented the web directories that existed up to now and largely replaced them to this day.

With the increasing complexity of formats, protocols and techniques, new job profiles emerged, such as B. Web designers and mediatricians. In addition to programming content, her tasks also include evaluating user behavior as part of log file analysis.

The WWW was developed in 1989 by further developing similar concepts by Tim Berners-Lee and Robert Cailliau at the European research center CERN in Geneva. ^{[2] [3]} Berners-Lee developed the HTTP network protocol and the text markup language HTML. He also programmed the first web browser and the first web server software. He also operated the world's first web server on his NeXTcube development computer. The overall concept was made available to the public in 1991 without any patenting or license payments, which contributed significantly to its current importance.

• • http://info.cern.ch/hypertextlWWWTheProject.html

The world's first website info.cern.ch was published on August 6, 1991. ^[4] A replica of this page can be reached via the following link:

• • http://info.cern.ch/hypertextlWWWTheProject.html

The WWW led to extensive upheavals, often described as revolutionary, in many areas of life, to the emergence of new economic sectors and to a fundamental change in communication behavior and media use. Its cultural significance, along with other Internet services such as e-mail, is sometimes equated with the invention of book printing.

functionality

• • HTTP als Protokoll, mit dem der Browser Informationen vom Webserver anfordern kann.
• • HTML als Auszeichnungssprache, die festlegt, wie die Information gegliedert ist und wie die Dokumente verknüpft sind (Hyperlinks).
• • URLs als eindeutige Bezeichnung einer Ressource, die in Hyperlinks verwendet wird.

The WWW is based on three core standards:

• • HTTP as a protocol with which the browser can request information from the web server.
• • HTML as markup language, which defines how the information is structured and how the documents are linked (hyperlinks).
• • URLs as a unique name for a resource that is used in hyperlinks.

The following standards were added later:

• • Cascading Style Sheets (CSS) determine the appearance of the elements of a website, whereby the presentation and content are separated.
• • Hypertext Transfer Protocol Secure (HTTPS) is a further development of HTTP, in which the SSL protocol is pushed between TCP and HTTP and the data transfer is then completely encrypted.
• • Document Object Model (DOM) as a programming interface for external programs or scripting languages of web browsers.

• • JavaScript ist eine Skriptsprache mit Anweisungen für den Browser, mit der Programme (Skripte) eingebettet werden können. Dadurch können Webseiten mit Hilfe des Document Object Models (DOM) dynamisch geändert werden. Skripte sind üblicherweise kleine Programme, können aber auch als Client Manager mit Hilfe des DOM die vollständige Kontrolle über die Anzeige übernehmen. Eine von Microsoft entwickelte Variante von JavaScript heißt JScript. Beide Sprachen sind ähnlich, allerdings nicht kompatibel zueinander. Diese Inkompatibilität war ein entscheidender Teil des sogenannten Browserkriegs.

The World Wide Web Consortium (W3C), which is now led by the inventor of the WWW Tim Berners-Lee, and others develop the HTML and CSS standards; other standards come from the Internet Engineering Task Force, ECMA, and manufacturers like Sun Microsystems. The most common scripting or macro language of web browsers is not standardized by the W3 consortium:

• • JavaScript is a scripting language with instructions for the browser with which programs (scripts) can be embedded. This allows websites to be changed dynamically using the Document Object Model (DOM). Scripts are usually small programs, but can also take complete control of the display as client managers using the DOM. A variant of JavaScript developed by Microsoft is called JScript. Both languages are similar, but not compatible with each other. This incompatibility was a crucial part of the so-called browser war.

The WWW has been and is being supplemented by other techniques. Images were used early for illustration; one used the formats GIF for graphics and animations and JPEG for photos. Later GIF was more and more replaced by PNG, because - unlike GIF - there were no license fees for its use.

In addition, numerous other file types could be displayed in browsers through browser extensions, so-called plug-ins. This made it possible to display multimedia content from animations to music and videos or entire applications such as insurance calculators or navigation interfaces. For example, Java applets made it possible to embed programs that run locally on the WWW user's computer, and Flash was used for interactive content or animation.

With the introduction of HTML5 and other standardized web technologies, plug-ins were quickly pushed out of the market, since the functions for animation and multimedia content or the like were now built directly into the browser and could therefore be implemented without external dependencies. For security and stability reasons, most larger browsers mostly deactivate large parts or the entire NPAPI interface that was used for these plug-ins. However, formats such as PDF for displaying documents are still popular, which can now mostly also be displayed using PDF readers installed in the browser.

Dynamic websites and web applications
→ Main article: web application

With the help of the dynamic WWW pages, the WWW can serve as an interface for distributed programs: A program is no longer started conventionally locally on the computer, but is a set of dynamic WWW pages that can be viewed and operated by a web browser. The advantage here is that the programs are no longer distributed on the individual computers and must be administered there (decentrally).

• • Ausführen von Webanwendungen am Webserver: Der Inhalt wird durch in Skriptsprachen (wie PHP oder Perl) oder kompilierte Anwendungen (wie JSP, Servlets oder ASP.NET) geschriebene Webanwendungen erzeugt und an den Browser geliefert.
• • Dynamische Websites am Client: Der Browser erzeugt oder ändert Inhalt mittels JavaScript.
• • Gemischte Ausführung: Eine gemischte Ausführung stellt AJAX dar - hier sendet der Browser mittels JavaScript einen Request, der vom Webserver bearbeitet wird und so dynamisch Teile der HTML-Struktur erneuert.

Dynamic web applications are either executed on the web server or directly in the browser.

• • Execution of web applications on the web server: The content is generated by web applications written in script languages (such as PHP or Perl) or compiled applications (such as JSP, Servlets or ASP.NET) and delivered to the browser.
• • Dynamic websites on the client: The browser creates or changes content using JavaScript.
• • Mixed version: AJAX represents a mixed version - here the browser sends a request via JavaScript, which is processed by the web server and thus dynamically renews parts of the HTML structure.

A disadvantage is the limited printability of WWW pages, so that programs in the form of Internet pages can generally not be operated as easily as conventional programs. One trend that is trying to reconcile the two is Rich Internet Applications.

• So wird Webmail oft als E-Mail-Client oder WebFTP als FTP-Client genutzt; Webforen ersetzen das Usenet und Webchats den IRC.

At the moment it can be observed that more and more services, which were originally separated from the WWW and ran as a separate program, are offered via the WWW and can be used using a browser:

• Webmail is often used as an email client or WebFTP as an FTP client; Web forums replace Usenet and web chats replace IRC.

Compatibility and accessibility

Browser manufacturers often introduced new possibilities without waiting for standardization. Conversely, however, not all parts of standards such as HTML or CSS are still implemented correctly. This leads to incompatibilities between certain websites and some browsers. At the beginning of the internet boom, the company Netscape, especially today the company Microsoft with its Internet Explorer, was particularly "excelled" by such incompatibilities.

In addition, due to the large number of ad hoc extensions to HTML, an essential advantage of this language was lost - the separation of content and presentation. Through this separation, the HTML-marked content can be optimally prepared for the respective output device - whether screen, cell phone display or voice output (for users with visual difficulties).

The W3C and other initiatives are therefore driving development towards standardization and cross-browser unification of HTML / XHTML and CSS to regain these advantages of HTML. The increasing absence of plug-ins such as Flash also supports this trend and has led to better accessibility. XHTML was later abandoned in favor of HTML5, which also incorporated explicit features to improve accessibility and machine readability that are not visually visible.

Cloud computing

(German computer cloud or data cloud) describes the provision of IT infrastructure such as storage space, computing power or application software as a service over the Internet.

To put it more technically, cloud computing describes the approach of making IT infrastructures available via a computer network without having to install them on the local computer.

These services are offered and used exclusively through technical interfaces and protocols, for example using a web browser. The range of services offered as part of cloud computing encompasses the entire spectrum of information technology and includes, among other things, infrastructure, platforms and software.

Definition

• Servicemodelle
• Cloud Computing enthält drei verschiedene Servicemodelle:
• Software as a Service (SaaS) Clouds bieten Nutzungszugang von Software-Sammlungen und Anwendungsprogrammen. SaaS-Diensteanbieter offerieren spezielle Auswahlen von Software, die auf ihrer Infrastruktur läuft. SaaS wird auch als Software on demand (Software bei Bedarf) bezeichnet.^[4]
• Platform as a Service (PaaS) Clouds bieten Nutzungszugang von Programmierungs- oder Laufzeitumgebungen mit flexiblen, dynamisch anpassbaren Rechen- und Datenkapazitäten. Mit PaaS entwickeln Nutzer ihre eigenen Software-Anwendungen oder lassen diese hier ausführen, innerhalb einer Softwareumgebung, die vom Dienstanbieter (Service Provider) bereitgestellt und unterhalten wird.
• Infrastructure as a Service (IaaS) Clouds bieten Nutzungszugang von virtualisierten Computerhardware-Ressourcen wie Rechnern, Netzen und Speicher. Mit laaS gestalten sich Nutzer frei ihre eigenen virtuellen Computer-Cluster und sind daher für die Auswahl, die Installation, den Betrieb und das Funktionieren ihrer Software selbst verantwortlich.

In 2011, the National Institute of Standards and Technology (NIST) published a definition ^[3] that met with widespread acceptance and bundled different definition approaches:

• Service models
• Cloud computing includes three different service models:
• Software as a Service (SaaS) clouds offer access to the use of software collections and application programs. SaaS service providers offer special selections of software that runs on their infrastructure. SaaS is also known as software on demand. ^[4]
• Platform as a Service (PaaS) clouds offer access to the use of programming or runtime environments with flexible, dynamically adaptable computing and data capacities. With PaaS, users develop their own software applications or have them run here, within a software environment that is provided and maintained by the service provider.
• Infrastructure as a Service (IaaS) clouds offer access to the use of virtualized computer hardware resources such as computers, networks and storage. With laaS, users can freely design their own virtual computer clusters and are therefore responsible for the selection, installation, operation and functioning of their software.

Delivery models

Presentation of cloud delivery models

In addition, the definition of the National Institute for Standards and Technology (NIST) contains four delivery models: ^[5]

Public cloud - the public computer cloud
Provides access to abstract IT infrastructures for the general public over the Internet. Public cloud service providers allow their customers to rent IT infrastructure on a flexible basis for paying for the actual level of use or consumption (pay-as-you-go), without having to invest capital in computer and data center infrastructure.

Private cloud - the private computer cloud
A private cloud is a cloud environment that is operated exclusively for an organization. The cloud platform can be hosted and managed internally (e.g. by the company's own data centers), but also by third parties.

Hybrid cloud - the hybrid computer cloud
Offers combined access to abstract IT infrastructures from the areas of public clouds and private clouds, according to the needs of their users.

Community Cloud - the community cloud
Provides access to abstract IT infrastructures such as those in the public cloud for a smaller group of users who share the costs, usually geographically distributed (e.g. several city authorities, universities, companies or companies with similar interests, research communities, cooperatives).

• Virtual Private Cloud - eine private Rechnerwolke auf prinzipiell öffentlichzugänglichen IT-Infrastrukturen Die Abschottung der „virtuell privaten“ Bereiche auf der öffentlichen Infrastruktur wird durch geeignete Sicherheitsmaßnahmen (z. B. VPN) gewährleistet.^[6]
• Multi Cloud - Bündelung verschiedener Cloud-Computing-Dienste Weiterentwicklung der Hybrid Cloud, bei der mehrere Cloud-Computing-Dienste in einer heterogenen Systemarchitektur gleichzeitig genutzt werden können.

There are also mixed forms of the above-mentioned cloud types:

• Virtual private cloud - a private cloud of computers on basically publicly accessible IT infrastructures The partitioning of the "virtually private" areas on the public infrastructure is guaranteed by suitable security measures (e.g. VPN). ^[6]
• Multi cloud - bundling of different cloud computing services Further development of the hybrid cloud, in which several cloud computing services can be used simultaneously in a heterogeneous system architecture.

Essential characteristics

• On-demand self-service Selbstzuweisung von Leistungen aus der Cloud durch den oder die Nutzer, die bei Bedarf bereitstehen soll.
• Broad network access Leistungen aus der Cloud sind über Standardmechanismen über das Netzwerk erreichbar.
• Resource pooling Ressourcen wie Rechenleistung, Netzwerk oder Storage werden zwischen unterschiedlichen Projekten und Kunden geteilt.
• Rapid elasticity Virtuelle Ressourcen skalieren schnell und aus Nutzersicht nahezu unbegrenzt und können auch automatisiert auf Laständerungen angepasst werden.
• Measured service Ressourcennutzung kann gemessen und überwacht werden. Zum Beispiel für Abrechnung oder auch automatische Skalierung.

The NIST lists five essential characteristics for cloud computing:

• On-demand self-service Self-assignment of services from the cloud by the user or users, which should be available when required.
• Broad network access services from the cloud are accessible via standard mechanisms via the network.
• Resource pooling Resources such as computing power, network or storage are shared between different projects and customers.
• Rapid elasticity Virtual resources scale quickly and from the user's point of view almost unlimitedly and can also be automatically adapted to changes in load.
• Measured service resource usage can be measured and monitored. For example for billing or automatic scaling.

As a result, cloud computing goes beyond other currently discussed approaches (e.g. virtualization). On the condition of public availability, similar to the public telephone network, for example, depending on the architecture, cloud computing can also be seen as the sum of SaaS and utility computing.

Differentiation from other techniques

“Grid computing” is about the shared use of shared resources and there is no central control. In the case of cloud computing, you have a provider of resources and a user. The management of resources is centralized.

Fog computing represents the decentralized expansion of cloud computing. Resources such as storage, computing power and software applications are placed closer to the end devices in order to achieve better efficiency and lower latency through optimized distribution. Only relevant and possibly compressed data is then sent to the central systems. Fog computing is closely related to edge computing, where, for example, sensor data is processed directly in the sensor system and then passed on to Fog and Cloud. There is a large overlap between fog and edge computing, which is why they are sometimes used interchangeably.

architecture

Since clouds were primarily created by the idea of scaling, the strongest distinguishing features can also be found there.

A simple computer can be imagined to approach the architecture. It has processor cores, memory, a hard drive and programs. These components can also be found in a cloud, only in a form that enables massive scaling.

As a result, the characteristics of a “cloud hard disk” read differently than that of a classic hard disk in a computer. Amazon says about its persistence layer (S3): "The number of objects that can be saved is unlimited." ^[13] Google has distributed its persistence layer Google File System to around 15,000 individual computers (as of 2009). [14]

Similar large dimensions apply to the other components such as programs or processor cores. The numbers alone explain why this is so. In 2008, Google announced that it would be able to sort 10 billion records across 1000 physical computers within 68 seconds.

"We are excited to announce we were able to sort 1 TB (stored on the Google File System as 10 billion 100-byte records in uncompressed text files) on 1,000 Computers in 68 seconds."

"We are pleased to announce that we were able to sort 1 TB (stored in the Google File System in 10 billion documents with 100 bytes of data set size in uncompressed text files), distributed across 1000 computers, within 68 seconds." ^{[ 15]}

Technical realizations of cloud computing

There are different types of cloud computing. A possible structure is the so-called technical cloud stack with three layers, in which upper layers can build on the lower layers, but do not have to: ^[16]

• • Anwendung
• • Plattform
• • Infrastruktur

Cloud computing architecture

• • Application
• • Platform
• • infrastructure

Each layer represents a degree of abstraction. In this way, the different types of "clouds" can also be classified.

Application (SaaS)
→ Main article: Software as a Service

The application layer represents the most abstract layer on cloud services. The user does not bring his application into a cloud platform, nor does he have to worry about scalability or data storage. He uses an existing application that offers the cloud to the outside world. This use case includes the two levels below, since the cloud functionalities such as upscaling, distributed storage, fail-safe infrastructure and usually a scaling queuing system are the basis of the application used, but the user of the SaaS service does not come into contact with it.

• • Das Design soll modular und serviceorientiert sein (Aufsetzbarkeit auf dem PaaS-Szenario).
• • Die Last ist nicht vorhersehbar, denn über Nutzungsintensität und Nutzerzahl einer Anwendung kann oft keine zuverlässige Aussage gemacht werden.
• • Die Anwendung soll dynamisch, verteilt und mandantenfähig sein.

A “cloud application” in the SaaS model typically takes the following aspects into account:

• • The design should be modular and service-oriented (can be placed on the PaaS scenario).
• • The load is unpredictable, because often no reliable statement can be made about the intensity of use and the number of users of an application.
• • The application should be dynamic, distributed and multi-client capable.

Well-known examples of cloud applications are Apple iCloud, Google Drive, Microsoft OneDrive, ownCloud, Nextcloud or Salesforce.com.

Platform (PaaS)

A developer creates an application and loads it into a cloud platform. This then takes care of the division among the actual processing units. In contrast to laaS, the user has no direct access to the computing instances. He also does not run any virtual servers. In the PaaS scenario, he only brings his program logic into the cloud platform, which acts as the programming interface.

The infrastructure of the cloud itself takes care of the required instantiation of the processing units and the distribution of the data to be processed.

As an example, the products Windows Azure from Microsoft, "App Engine" from Google or "force.com" from Salesforce.com can be assigned to the platform layer.

Because the user only supplies his application logic here, the cloud platform can increase or reduce the number of actually working instances at will. The abstraction of any technical component is explicitly desired, since the cloud user primarily processes data, but does not want to administer the system.

Infrastructure (laaS)
→ Main article: Infrastructure as a Service

The infrastructure or “cloud foundation” represents the bottom layer in cloud computing. Here, the user accesses existing services within the system, but largely manages his computing instances himself (see virtual server). Services within the laaS concept are typically distributed persistence (see Amazon's Simple Storage Service) and a message service (see Message Oriented Middleware). If the cloud services themselves are still scaled up, this does not necessarily apply to the programs that run on the computing instances introduced by the user.

The advantage over traditional data centers is the scalability: The computing instances can be expanded or reduced as required by additional instances. The user has full access to the instances with the property that he is responsible for the instances from the operating system level.

The biggest examples of this are Amazon Web Services and the Open Telekom Cloud.

Organizational types of clouds

In addition to the technical cloud stack, you can also differentiate between different organizational forms of “clouds”, which are justified depending on the application. The definitions for the terms “private”, “public” etc. were coined by NIST, are used in the same way by auditors (ISACA is the leader for the definition of the standards) and have also been in ISO / IEC 17788 since 2014 available. The definitions by these committees are of great value because the correct definitions of the deployment models are internationally valid.

In summary, it can be said that the definitions refer to the possible group of users and have nothing to do with where “the cloud” is operated or what the ownership structure looks like. “Private cloud” is understood to mean a cloud in which the resources are addressed by a predefined user group and where the administration is carried out by excellent users. At the other end of the scale is the "public cloud", where a priori no information about the possible ones User exists. Mixed forms in between are possible (eg "Hybrid Cloud"), but also refer to the user group and not to the technical design.

The terms, as they are commonly found, and in the context of their use "public cloud" equated with "off premise" and "private cloud" with "on premise" are misleading and do not correspond to the basic idea of ISO / IEC standards or those of other bodies.

Cloud computing in the economy

Cloud computing shifts the investment for application programs to the service provider and a fee corresponding to the actual performance. This makes it possible to replace cumbersome decision-making processes in the company ordering the services.

Advantages and problems

Like virtualization, cloud computing enables cost advantages ^[17] compared to conventional systems. This is the case if, for example, payment is based on the length of use of the service and the service is only used occasionally. Local resources (software and hardware) can be saved. This resource efficiency is also increasingly being associated with the sustainable use of ICT systems, although corresponding considerations are by no means new. A frequently cited example is the implementation of e-mail systems based on cloud computing, because here the complexity of the application increases due to measures to prevent attempts to compromise, so that smaller companies can benefit from outsourcing. There are also advantages in the case of strongly fluctuating demand: Normally one would have to have enough capacity to be able to handle peak loads. When using cloud computing, the capacity used can be variably adapted to actual needs at short notice. This applies particularly to volatile business areas that have to meet external requirements immediately, such as logistics. Constantly fluctuating and market-dependent goods volumes require prompt reaction and the constant availability of the capacities required for execution. Thanks to the flexibility and scalability of the cloud, the provision of required resources for logistic software (such as WMS, TMS, ERP etc.) would be much cheaper and easier to do than is currently the case with static systems. According to a current study by the Fraunhofer Institute for Material Flow and Logistics IML, a cost reduction in warehouse management can be reduced by up to 56 percent in the first year and 48 percent in the following years. ^[18] Concepts for practical implementation exist and are already in use. ^[19] Further cost advantages result for the service user with public cloud offers, for example in IT governance (for example through (partial) outsourcing of the IT audit to the service provider), through the lower investment requirements and the (tax and commercial law) approach of the monthly fees in full. ^[20]

• Eines der Grundprobleme, nämlich die Absicherung des Zugriffs auf die Anwendungsdaten beim Transfer zwischen lokalem Client und entferntem Server, kann heute befriedigend gelöst werden. Es existieren zahlreiche Entwicklungen im Bereich der sicheren Übertragung, wie beispielsweise SSL/TLS-Verschlüsselung. Ein weiteres Grundproblem ist die Verschlüsselung der Daten, die in Datenbanken und Datei-Systemen der Cloud gespeichert werden. Auch dieses Problem ist grundsätzlich technisch gelöst und wird von State-of-the-Art-Cloud-Anbietern angewandt (Kryptographie). Jedoch findet man (Stand 2012) hierauf noch keine Hinweise in den Datenschutzerklärungen der großen Cloud-Anbieter.

Data security is problematic in cloud computing:

• One of the basic problems, namely securing access to the application data during the transfer between the local client and the remote server, can be solved satisfactorily today. There are numerous developments in the area of secure transmission, such as SSL / TLS encryption. Another basic problem is the encryption of the data that is stored in cloud databases and file systems. This problem is also fundamentally technically solved and is used by state-of-the-art cloud providers (cryptography). However (as of 2012) there are still no references to this in the data protection declarations of the major cloud providers.

The third basic problem, namely that administrators of the cloud provider and the services have access to the user data during processing, on the other hand, cannot be solved without complex management of distributed authentication and dynamic authorization as well as cryptography.

Critics claim that control of users' private data by market-dominant providers, such as Google, is taking over. ^[21] However, there are now algorithms that can split calculations into individual instances in such a way that even all instances cannot jointly draw conclusions about the processed data. ^[22] This is only possible for the executing agency, since only they know the exact algorithm with which the partial results are brought together again. Another approach that can be used to solve this problem is to use fully homomorphic encryption. In the cloud, only encrypted data is used, which can then be decrypted in the private area. The challenge is here however, in finding encryption algorithms that work efficiently enough for massive, large-scale use in cloud computing.

An alternative approach that also makes the data in the cloud inaccessible is the concept of the sealed cloud. A key distribution is used, which allows the data to be encrypted but not decrypted by the keys that are accessible to the administrators, and there is an orderly backup and subsequent deletion of unencrypted data before an administrator, for example for maintenance purposes, Get access to the computing infrastructure.

Another challenge in the cloud is the dependency (lock-in effect) on the respective cloud provider, since the interfaces offered are usually very manufacturer-specific. Home users are also faced with the hypothetical question of what happens to their data in the cloud when the provider of a cloud service files for bankruptcy. ^[23] Therefore, new providers offer the restore of the data on your own computer. ^[24]

costs

There are various studies on the costs of cloud computing. According to a study by Dachyuk (2018), colocationing is cheaper than cloud computing from around 150 large AWS instances (m4.2xlarge). ^[25]

Replacement solutions

As many home users are increasingly concerned about storing their data with large companies, for example if they could change their terms and conditions at any time, many NAS systems provide home functions that are familiar from cloud storage operators. In this case, one speaks of a personal cloud, since the data storage infrastructure is operated entirely by the user. However, NAS solutions do not process data.

Differentiation from other forms of service

Cloud computing is related in some elements to classic online outsourcing. However, it differs from this in essential points. In the area of infrastructure as a service providers, the IT infrastructure is generally used by several customers, so that peak capacity can be distributed more easily and reserves can be shared. In this way, cloud services can be adapted at short notice and differ from the classic model in which customers use the computer infrastructure “exclusively”. Furthermore, the user controls and administers the services via the web interface itself. ^[2]

Legal issues

Legally, the relationships between cloud providers and their customers as well as the rights of affected third parties must be considered.

Data security

It must be taken into account that the legally required data protection cannot be achieved without technical data security. Data security is determined by the technology used by the provider and the applications used by the provider.

privacy

According to the judgment of the European Court of Justice, only limited data can reach the USA, where over 90% of the cloud computing infrastructure is located. ^[26] National data protection agencies rely on the work of ENISA when they explain why cloud computing is illegal for schools, for example, despite Safe Harbor. ^[27] The data protection officers in Switzerland also warn against the violation of data protection law when using data centers abroad. ^[28]

If personal data of third parties are stored online, German clients, for example, must convince themselves beforehand and then regularly, on site, that the The requirements of the Federal Data Protection Act are observed. ^[29] Because well-known cloud providers share their customers' databases, customers face fines. ^[30] Cloud operators based in the United States are subject to US law and therefore the Patriot Act. Companies based in the USA are therefore forced to supply data to American authorities that are located on servers in a foreign jurisdiction. This has been confirmed by Amazon, Microsoft and Google, for example. ^[31]

Not least because of these data protection problems and to what extent individuals actually retain control over their data, cloud and cloud computing technology received the 2012 Big Brother Award negative in the "Communication" category, which was laudated by Rena Tangens from FoeBuD

Performance liability

For cloud-specific services, web or file space, databases, applications and hosting services are usually made available. With web hosting (possibly also for storage management), in which data is stored on the host of the hosting provider, it is believed that this is not a rental contract according to §§ 535 ff. BGB, but a contract for work according to §§ 631 ff. BGB. The hosting provider only owes as a service that the customer's website is stored somewhere with him and that it can be accessed on the Internet. The actual service is therefore the storage of the information and its availability for retrieval on the Internet. It is particularly important for the customer that the content is permanently available. The customer is indifferent to how the hosting provider or cloud provider provides this service. This does not primarily leave storage space, but primarily a success, namely accessibility on the Internet. Saving the website is only a technical requirement for the success owed.

When making applications available, a software-as-a-service (SaaS) or “application service providing” (ASP) model is usually selected. The ASP provider makes the temporary use of applications available to a customer. The Federal Court of Justice has ruled ^[33] that the tenancy law provisions generally apply to application service providing contracts. Even if this decision was certainly significant, a considerable contractual arrangement is required, especially when designing the service levels, since the tenancy law provisions of §§ 535 ff. BGB alone should not be sufficient here.

The classification of hosting contracts for databases in the contract typological classification of the BGB is based on the contractually owed service. It is important to distinguish whether Filespace is provided by the provider for storing the database (so-called database hosting) or an application such as an Oracle database (for temporary use) as described above. Does the cloud IT provider owe services beyond the hosting service, such as B. when designing the databases, the regulations of §§ 87a to 87e UrhG may have to be considered.

copyright

Copyright issues should also be taken into account when data protected by copyright are stored online. From a legal point of view, the upload of data is nothing more than a reproduction according to 16 UrhG, which requires the consent of the author. Only if the upload is for purely private purposes and the file is not made publicly available can the upload be made as a private copy. 53 UrhG may be permissible. However, making files of the cloud publicly available (Section 19a Copyright Act) is always illegal without the author's consent.

In addition, according to Marcel Bisges, cloud computing can undermine the current system of copyright remuneration by reducing the author's right to reasonable remuneration (for private copies). ^[34] From a copyright perspective, cloud computing, on the other hand, is, according to Bisges, advantageous for software manufacturers because, in contrast to conventional software leasing, the damage caused by illegal copies is avoided. ^[35]

Cloud services made in Germany

• • Das Unternehmen des Cloud-Service-Betreibers wurde in Deutschland gegründet und hat dort seinen Hauptsitz.
• • Das Unternehmen schließt mit seinen Cloud-Service-Kunden Verträge mit Service-Level-Agreement (SLA) nach deutschem Recht.
• • Der Gerichtsstand für alle vertraglichen und juristischen Angelegenheiten liegt in Deutschland.
• • Das Unternehmen stellt für Kundenanfragen einen lokal ansässigen, deutschsprachigen Service und Support zur Verfügung.

The Cloud Services Made in Germany initiative was launched in Germany in 2010. This is about legal security when using cloud computing solutions. Because with the companies The customers involved are located exclusively in Germany and are therefore subject to German law and data protection. The following aspects are important for the initiative: ^[36]

• • The company of the cloud service operator was founded in Germany and has its headquarters there.
• • The company concludes contracts with its cloud service customers with a service level agreement (SLA) under German law.
• • The place of jurisdiction for all contractual and legal matters is Germany.
• • The company provides local, German-language service and support for customer inquiries.

Cloud commerce

Cloud commerce is a connection between the areas of e-commerce and cloud computing. Specifically, the topic of cloud commerce only deals with the sub-area software as a service of cloud computing, or SaaS for short. In this case, the software offered in the SaaS model is an eCommerce system (primarily a shop system).

Analogous to the SaaS model, cloud commerce is based on the principle that the eCommerce system and the IT infrastructure are operated by an external IT service provider, the manufacturer of the software, and used by the customer as a service. The service provider takes over the complete IT administration and other services such as maintenance work and updates. For this purpose, the entire IT infrastructure, including all administrative tasks, is outsourced, and the service recipient can concentrate on his core business. ^[1] SaaS models, such as cloud commerce, are becoming increasingly important. Market research company Gartner forecast sales of $ 12.1 billion in 2011. This means an increase of 20.7 percent compared to the previous year (2010: $ 10 billion). The North American market represents the largest aggregate of demand (2011: $ 7.7 billion). ^[2] Cloud commerce offers small and medium-sized companies a variety of advantages over traditional license purchases and the own operation of an IT infrastructure.

advantages

• • Low investment risk
• • Transparent IT costs
• • Accelerated implementation
• • Reduction of IT process complexity
• • Mobility
• • Concentration on the core business

The service recipient has a lower investment risk because he does not need any IT hardware for the software implementation. Two studies by McKinsey Consulting and Yankee Group state that the investment costs of a SaaS solution such as cloud commerce can be reduced by 30 percent compared to an on-premise solution, regardless of the number of users. ^[3] Another advantage is the outsourcing of process complexity, as maintenance work, updates and other IT tasks are carried out by the service provider. Software access via the Internet ensures a high degree of mobility, since the service recipient can access the system regardless of time and location. ^[4] With an outsourced IT infrastructure, companies can concentrate on their core business or value creation and thus avoid the annoying IT tasks. This makes IT an easy-to-use commodity to secure growth, flexibility, competitiveness and thus the existence of the company. ^[5]

disadvantage

• • Dependence on the service provider
• • Less customization options
• • Data and transaction security

A disadvantage of cloud commerce software is that the service users are in a dependency relationship because the customer is not the owner of the software. There is a risk that the service provider will shut down the system for a specific reason (e.g. in the event of bankruptcy). ^[4] The SaaS solutions are mostly standardized, so that there are few options for adapting the range of functions. ^[4]

From the perspective of the service provider

For the service provider, there are advantages and disadvantages through cloud commerce, which are described below:

• • Erweiterung des IT-Leistungsangebots und Erzielung zusätzlicher Umsatzerlöse
• • Längerfristig gesicherte Einnahmen und bessere Liquiditätsplanungsoption
• • Geringere Wahrscheinlichkeit des Auftretens von Softwarepiraterie

advantages

• • Expansion of the IT service offering and generation of additional sales
• • Long-term secured income and better liquidity planning option
• • Software piracy is less likely to occur

The service provider has the opportunity to expand its range of IT services and thus generate additional revenue. Since the service recipient usually pays monthly fees for the use of the software, longer-term income can be secured and thus the liquidity can be better planned. In addition, fewer losses are achieved through software piracy, since the software is managed centrally by the service provider. ^[6]

• • Investitionsrisiko
• • Akzeptanzprobleme auf dem IT-Markt
• • Möglicher Imageschaden und Umsatzverluste

disadvantage

• • Investment risk
• • Acceptance problems in the IT market
• • Possible damage to image and loss of sales

The cloud commerce provider has the problem of high investment risk if the software is not accepted by the customer as expected. In addition, he has to convince the customer, because current acceptance problems are often justified with the disadvantages.

privacy

In cloud commerce, the customer or sales data of the customer are no longer on their own computers, but with the respective system provider. There is regularly a case of order data processing between the provider and his customer in accordance with Section 11 of the Federal Data Protection Act (BDSG). The customer is obliged to select the provider carefully, to check it regularly and to document the result of the checks. The customer remains responsible for the legality of the data processing.

Cloud commerce company

Examples of cloud commerce offerings are e.g. B. Magento Go, Amazon Webstore and Shopify in the United States; Big Cartel in the UK; Big Commerce in Australia; Supr.com as well as XSITE, Jimdo and Onshop.de in Germany.

Online data backup

Online data backup, online backup or web backup means data backup over the Internet. This takes place on data storage devices of an Internet service provider in a data center.

The procedure relieves the user of procuring reliable data storage himself, regularly checking it, managing it and securing it against loss.

method

After registration, the customer receives a user name and a password for access to the data backup. Internet access is a technical requirement. The software for data backup or Uploading via a website should also ensure secure encryption in order to protect the transmitted data from unauthorized access.

Because the data transfer rate of Internet access is usually only a fraction of that of drives and local area networks, the software can perform data compression as far as possible. Already compressed data - for example in the file formats ZIP, JPEG, MPEG or MP3 - can hardly be compressed any further.

Internet access with a data transfer rate of 1 Mbit / s can theoretically transfer 450 MB per hour or 10.5 GB per day. For example, this is a possible data transfer rate when uploading via ADSL 6000 in Germany. With faster internet access such as B. via VDSL, even higher data transmission speeds are possible. Some service providers offer to exchange large amounts of data by hard drive or DVDs by post, which is particularly useful for a larger initial backup.

Because of the relatively low data transfer rate, the method of incremental data backup, in which only new and changed data is copied, is of particular importance. Some providers use their software to search files for changed parts and only transfer the changed data blocks to the data store (block level). Some recognize that files have only been renamed and do not retransmit them. Renamed file folders and moved files cannot always be recognized, which can lead to new file transfers.

Some solutions such as B. Netzdrive, Novell iFolder, Dropbox, Fabasoft Folio Cloud or Recovery Guard offer features such as encryption of data on the server, assignment of file access rights to certain other users or user groups, replication of data to multiple servers and version control of Changes to which result in properties similar to those of so-called distributed file systems. If access can be restricted, the functionality of this software partially overlaps with that for file sharing.

Some solutions maintain their server structure exclusively in Germany, which is why all data traffic is subject to the strict German data protection laws, with the result that additional protection against unauthorized access is required. Few solutions also offer end-to-end encryption, through which the data is already encrypted locally on your own computer and is therefore securely encrypted on the way to the server.

Modern providers not only offer online backup in their software, but also parallel backup to local media, such as a tape drive or USB peripherals. Companies should make sure that SQL databases such as B. Microsoft SQL Server are supported and a complete system disaster recovery is included in the event of a server failure. A direct virus scanner integrated in the online backup software is also useful, which checks the data to be backed up or restored and thus increases the security of the backup.

Blockchain

A blockchain is a decentralized database that maintains a constantly growing list of transaction records. The database is expanded in a chronologically linear manner, comparable to a chain, to which new elements are constantly added at the lower end (hence the term "blockchain" = "blockchain"). If one block is complete, the next is created. Each block contains a checksum of the previous block.

The technical model of the blockchain was developed as part of the cryptocurrency Bitcoin - as a web-based, decentralized, public accounting system for all Bitcoin transactions that have ever been made. The Bitcoin blockchain is growing steadily as new blocks with newly completed Bitcoin transactions are added. Each computer that is connected to the Bitcoin network, generates new Bitcoins and / or manages the ones generated so far, manages a 1: 1 copy of the complete blockchain, which was already around 50 gigabytes in size at the end of 2015. Wikipedia has even more detailed technical information on the Bitcoin blockchain.

What is what with blockchain, bitcoin and Co.?

Ethereum

Another cryptocurrency based on the blockchain principle. Offers a platform for programmable smart contracts. The "Ether" are viewed by fans as the legitimate successor to the Bitcoins (see also picture above).
Ethereum.org
Photo: Anastasiia Bakay - shutterstock.com

What is Bitcoin?

Bitcoin is a purely digital currency - founded in 2009 - which is based on a decentralized payment network and which needs a blockchain as the backbone. If you pay with Bitcoins on the web, you pay lower transaction fees than with traditional online payment providers. Another possible advantage of Bitcoin is that the currency is not controlled by a central state bank or similar institution. Disadvantages are the manageable number of acceptance points and the now very high effort to calculate new bitcoins - their value increases accordingly.

There are no physical bitcoins, only account balances that are linked to public and private keys. These account balances are stored in a public accounting system - the blockchain - along with all Bitcoin transactions ever made. The computing power required to manage this massive amount of data is provided by a large network of computers.

What makes the blockchain so special?

Blockchain is arguably the greatest technological invention in the Bitcoin universe. Without blockchain, the Bitcoin system would not work because new bitcoins can only be calculated on the basis of the bitcoins previously generated and therefore it has to be tracked what has happened in the past. Nevertheless, the blockchain principle must be viewed separately from Bitcoin. Think of the blockchain as a pipe and Bitcoin as the water that flows through it. Or blockchain as a street and Bitcoin as a car. The following clou: On the basis of blockchain technology, new applications can be developed and completely new ecosystems established.

What are the advantages and disadvantages of decentralized technology such as blockchain?

• • Schutz großer Datenmengen mittels Verschlüsselung und Zugriffsverwaltung;
• • Möglichkeit, große Datenmengen unternehmensübergreifend zu sammeln und analysieren;
• • einfachere Verifzierung von Datenbezugspunkten;
• • automatische Aufspüren von Schwachstellen in der Lieferkette, im Zahlungsverkehr und anderen Geschäftsprozessen;
• • Reduktion oder Vermeidung von unnötigen Kosten für die IT-Infrastrukur;
• • Reduktion der Kosten für interne und externe Finanztransaktionen, Finanzreporting und Verwaltung;
• • Schaffung eines Mechanismus zur Verbesserung des Vorstandsreportings und des regulatorischen Reportings;
• • Beschleunigung des Jahresabschlusses.

The decentralization of IT in general and blockchain in particular has several advantages and disadvantages. The following can be mentioned as advantages:

• • Protection of large amounts of data using encryption and access management;
• • Ability to collect and analyze large amounts of data across companies;
• • easier verification of data reference points;
• • automatic detection of weaknesses in the supply chain, in payment transactions and other business processes;
• • Reduction or avoidance of unnecessary IT infrastructure costs;
• • Reduction of costs for internal and external financial transactions, financial reporting and administration;
• • Creation of a mechanism to improve board reporting and regulatory reporting;
• • Accelerate annual accounts.

• • noch wenig individuelle Skalierbarkeit;
• • geringer Datendurchsatz;
• • Einschränkungen beim Speicherplatz;
• • schwer zu verwaltende Berechtigungen;
• • schwierige Integration mit bestehender Legacy im Unternehmen.

Disadvantages include:

• • still little individual scalability;
• • low data throughput;
• • Space restrictions;
• • difficult to manage permissions;
• • Difficult integration with existing legacy in the company.

How is blockchain used in the financial industry?

Many things are already decentralized in IT - thanks to the Internet and the cloud. With applications that are based on the blockchain principle, new developments are added that will ensure that the disadvantages listed are gradually eliminated. The cryptocurrency Ethereum is based on the blockchain principle of decentralized computing power and can be seen as a kind of bridge between blockchain and corporate systems.

The "scalable blockchain database" BigchainDB can manage up to one million write operations per second, store petabytes of data and still comes up with a latency of less than one second - all managed decentrally and with the highest data integrity.

Blockchain application platforms for the financial industry that are still in development - such as ERIS or R3CEV - are supposed to set up the "business rules" of blockchain technology and bring new transparent, secure and verifiable business models to IT, especially the financial sector. For the CIO, such a new decentralized technology stack and growing ecosystem means that it can do its job better: faster completion for business operations, safer transaction processing, cost reduction and closer orientation to regulatory requirements.

Integration with existing systems is still a challenge, but it is not insurmountable and can be justified with the advantages to be expected from blockchain for both IT and business.

Why can other industries also benefit from the blockchain?

IT is increasingly developing decentralized structures because users want to keep an eye on their digital data themselves. Decentralized systems allow information to be stored in a network of several computers that can be accessed via the Internet. The decentralization of communication began with the Internet and everyone was given more control over the information they consume. In the next step, computing power and storage will be decentralized in addition to communication (cloud computing), and with the blockchain there is now another element. The blockchain fires ideas not only to control cryptocurrencies such as Bitcoin via decentralized networks, but also other digital content such as art, music, texts or photos.

We have compiled the first concrete practical examples for the use of blockchains in various industries in the article "Blockchain in use".

What do the blockchain offerings of the large IT companies look like?

Large IT companies jump on the blockchain train and are currently tinkering with software and service ecosystems around the technology. For example, IBMsowieso has long been actively involved in the Linux Foundation's Bitcoin initiative - within its cloud developers the opportunity to set up their own blockchains. Big Blue has made the Hyperledger code on which the Bitcoin blockchain is based available on its developer platform Bluemix.

Through the simultaneous integration of the Docker container service, it is "now possible for developers to get their own mini-blockchain up and running within a sandbox in twelve seconds," as Jerry Cuomo, responsible for blockchain offers at IBM, as part of the Presentation of the services in February 2016 underlined. "And just a minute later, the first complete blockchain application is live."

Microsoft has also recognized the benefits of blockchain and launched the "Project Bletchley" in the Azure Cloud under the umbrella of "Ethereum Blockchain as a Service". In the near future, various middleware tools will be launched that expand the business benefits of blockchain. For example, "Blockchain as a Service" primarily addresses developers. So-called “cryptlets” serve as the technical tools of the solutions, with the help of which users can insert external data into a blockchain without destroying their security and integrity.

These cryptlets can be developed in any programming language and run analogous to the IBM offer within a secure container. Microsoft plans to use blockchain technology all in security-relevant topics such as identity management and encryption and has already integrated corresponding services in Project Bletchley.

Other large IT players such as SAP or HPE have also been keeping an eye on the technology for some time and, according to their own statements, are still evaluating the possibilities of developing offers around blockchain.

A blockchain ^{[1] [2] [3]} (also block chain, ^{[4] [5]} English for blockchain) is a continuously expandable list of data records, called "blocks", which are linked together using cryptographic methods. ^{[1] [6]} Each block typically contains a cryptographically secure hash (scatter value) of the previous block, ^[6] a time stamp and transaction data. ^[7]

The term blockchain is also used when an accounting system is managed decentrally and the correct state must be documented because many participants are involved in the accounting. This concept is referred to as distributed ledger technology (decentralized account technology) or DLT. ^[8] What is to be documented is irrelevant to the term blockchain. It is crucial that later transactions build on previous transactions and confirm these as correct by proving knowledge of the previous transactions. This makes it impossible to manipulate or redeem the existence or content of previous transactions without also destroying all later transactions. Other participants in decentralized accounting who still have knowledge of the subsequent transactions would recognize a manipulated copy of the blockchain by the fact that it has inconsistencies in the calculations.

The process of cryptographic chaining in a decentralized accounting system is the technical basis for cryptocurrencies, but can also help to improve or simplify transaction security in distributed systems compared to central systems. One of the first uses of blockchain is the cryptocurrency Bitcoin.

The way it works is similar to the journal of accounting. It is therefore also referred to as the “Internet of values”. A blockchain enables unity to be achieved between the nodes in a decentralized network. (See also: Byzantine error.)

history

The first basics of cryptographically secured chaining of individual blocks were described in 1991 by Stuart Haber and W. Scott Stornetta, in 1996 by Ross J. Anderson and in 1998 by Bruce Schneier & John Kelsey. ^In 1998 Nick Szabo also worked on a mechanism for a decentralized digital currency, which he called "Bit Gold". ^[10] In 2000, developed Stefan Constitution a general theory to cryptographically secured chains and derived from different solutions to implement from. ^{[9] [11]}

The concept of blockchain as a distributed database management system was first described in 2008 by Satoshi Nakamoto in the white paper on Bitcoin. ^[12] The following year, he published the first implementation of the Bitcoin software and thus launched the first publicly distributed block chain.

properties

• • Verkettungsprinzip: Eine Blockchain ist eine verkettete Folge von Datenblöcken, die über die Zeit weiter fortgeschrieben wird.
• • Dezentrale Speicherung: Eine Blockchain wird nicht zentral gespeichert, sondern als verteiltes Register geführt. Alle Beteiligten speichern eine eigene Kopie und schreiben diese fort.
• • Konsensmechanismus: Es muss sichergestellt werden, dass eine bei allen Beteiligten identische Kette entsteht. Hierfür müssen zuerst Vorschläge für neue Blöcke erarbeitet werden. Dies geschieht durch Validatoren (die bei Bitcoin „Miner“ genannt werden). Dann müssen sich die Beteiligten einigen, welcher vorgeschlagene Block tatsächlich in die Kette eingefügt wird. Dies erfolgt durch ein sogenanntes Konsensprotokoll, ein algorithmisches Verfahren zur Abstimmung.
• • Manipulationssicherheit: Durch kryptographische Verfahren wird sichergestellt, dass die Blockchain nicht nachträglich geändert werden kann. Die Kette der Blöcke ist somit unveränderbar, fälschungs- und manipulationssicher.
• • Transparenz / Vertraulichkeit: Die auf der Blockchain gespeicherten Daten sind von allen Beteiligten einsehbar. Sie sind deshalb aber nicht unbedingt auch für alle sinnvoll lesbar, denn Inhalte können verschlüsselt abgespeichert werden. Blockchains erlauben so eine flexible Ausgestaltung des Vertraulichkeitsgrads.
• • Nichtabstreitbarkeit: Durch die Nutzung digitaler Signaturen sind Informationen in der Blockchain speicherbar, die fälschungssicher nachweisen, dass Teilnehmende unabstreitbar bestimmte Daten hinterlegt haben, etwa Transaktionen angestoßen haben.^[15]

New blocks are created using a consensus process and then attached to the blockchain. ^[13] The most popular consensus procedure is the proof-of-work method; However, there are numerous other forms of establishing consensus (proof of stake, proof of capacity, proof of burn, proof of activity). Due to the sequential storage of data in a blockchain, it cannot be changed afterwards without damaging the integrity of the overall system. This makes data manipulation considerably more difficult. The decentralized consensus mechanism replaces the need for a trusted third party to confirm transaction integrity. ^[14]

• • Chaining principle: A blockchain is a chained sequence of data blocks that is continued over time.
• • Decentralized storage: A blockchain is not stored centrally, but is kept as a distributed register. All participants save their own copy and continue to update it.
• • Consensus mechanism: It must be ensured that an identical chain is created for all involved. For this, suggestions for new blocks must first be worked out. This happens through Validators (called “miners” at Bitcoin). Then the participants have to agree on which proposed block will actually be added to the chain. This is done through a so-called consensus protocol, an algorithmic procedure for voting.
• • Tamper-proof: Cryptographic procedures ensure that the blockchain cannot be changed afterwards. The chain of blocks is therefore immutable, tamper-proof and tamper-proof.
• • Transparency / Confidentiality: The data stored on the blockchain is visible to everyone involved. However, they are not necessarily meaningfully legible for everyone, because content can be saved in encrypted form. Blockchains allow a flexible configuration of the level of confidentiality.
• • Non-contestability: By using digital signatures, information can be stored in the blockchain that can be tamper-proof that participants have undeniably stored certain data, such as initiating transactions. ^[15]

At Bitcoin, a blockchain consists of a series of data blocks, in each of which one or more transactions are combined and provided with a checksum, i.e. they are combined in pairs to form a hash tree. The root of the tree (also called Merkle root, or top hash) is then saved in the associated header. The entire header is then also hashed; this value is saved in the header below. This ensures that no transaction can be changed without also changing the associated header and all subsequent blocks. ^[16]

Bitcoin's blockchain is the oldest blockchain. It started in January 2009, had a size of approx. 144.5 GB ^[17] at the beginning of December 2017 and was redundant and publicly accessible on December 9, 2017 at approx. 11,900 nodes ^[18] .

Application example auditing

Auditing in information technology is about recording security-critical operations of software processes. This applies in particular to accessing and changing confidential or critical information. Auditing is suitable for a blockchain because it produces relatively small amounts of data and at the same time has high security requirements.

A blockchain can protect the audit log (also known as the audit trail) from changes. In addition, the individual entries should be provided with a digital signature to ensure authenticity. A decentralized consensus mechanism, like Bitcoin, is not absolutely necessary. ^[19]

Since on the one hand confidential information is stored and on the other hand no element of the blockchain can be deleted without invalidating it, the individual entries can also be encrypted. ^[19] Since the implementation of blockchains is currently (as of May 2017) very complex due to the lack of easy-to-use implementations, the use is only recommended for particularly sensitive information.

Examples of use include auditing systems for medical information (e.g. electronic health records), contracts and monetary transactions with high financial value, military secrets, legislation and electronic voting, security management of critical systems or data from large companies that are classified as Sarbanes- Oxley Act or similar guidelines fall.

As it became known in July 2018, the four accounting firms Deloitte, KPMG, PricewaterhouseCoopers International and Ernst & Young are testing a blockchain service for checking the interim reports of stock corporations. The aim is to give auditing companies the opportunity to track business transactions in a decentralized manner using a traceable and tamper-proof data chain, which optimizes and automates the confirmation process. ^{[20] [21]}

Application example capital markets

The blockchain is also being considered as an application in the capital markets. The R3 consortium has published the platform Corda with several financial institutions, which is supposed to be a substructure for blockchain applications for capital markets.

The main areas of application for capital markets are in the area of the settlement of stocks and other financial instruments, the issuance of syndicated loans and the financing of companies with equity.

Application example supply chains for food

The use of a blockchain, in which the parties involved jointly document the transactions in the supply chain, can result in significant cost and time savings. A blockchain could put an end to distrust of a central register-keeping actor, since a blockchain register is accessible to all participants. The accounting and reading rights can be distributed in stages, adapted to the different user groups and their needs, such as manufacturers, freight forwarders, customs and various consumers. This means that there is no complete transparency that competitors can exploit. For end users, for example, only reading rights can be granted, based on which the origin and the entire supply chain from harvest to processing, logistics, customs clearance, certification, food monitoring, wholesalers to retailers can be transparently and verifiably verified.

There is also automation potential for the documentation requirements to be complied with: For example, a sensor installed in the container could measure the temperature of food, write the measurement data into the blockchain and thus document complete compliance with the cold chain. If it was not adhered to, a smart contract set up accordingly could automatically raise the alarm. ^[22]

Informational self-determination

In Germany's right, the right to informational self-determination is the right of the individual to determine, in principle, himself about the disclosure and use of his personal data. According to the case law of the Federal Constitutional Court, it is a basic data protection right that is not expressly mentioned in the Basic Law for the Federal Republic of Germany. The proposal to insert a basic data protection right into the Basic Law has so far not found the required majority. However, personal data are protected according to the General Data Protection Regulation and Art. 8 of the EU Charter of Fundamental Rights.

General

The concept of the right to informational self-determination goes back to an expert opinion by Wilhelm Steinmüller and Bernd Lutterbeck from 1971. The right to informational self-determination is an expression of the general right of personality and was recognized by the Federal Constitutional Court in 1983 in the so-called census ruling ^[1] as a fundamental right. The starting point for the Federal Constitutional Court is the so-called general right of personality (APR), ie Art. 2 Para. 1 GG in conjunction with Art. 1 Para. 1 GG. ^[2]

Self-determination in the free development of the personality is endangered by the conditions of modern data processing. Those who do not know or cannot influence which information regarding their behavior are stored and kept in stock will adjust their behavior out of caution (see also: Panoptism). This affects not only individual freedom of action, but also the common good, since a freely democratic community needs the self-determined participation of its citizens. "The right to informational self-determination would not be compatible with a social order and a legal order that enables it, in which citizens can no longer know who knows what, when and on what occasion." ^{[Reference required]}

• „Jede Person hat das Recht auf Achtung ihres Privat- und Familienlebens, ihrer Wohnung und ihrer Korrespondenz.“

The European Parliament believes that the right to informational self-determination also derives from Article 8 (1) of the European Convention on Human Rights:

• "Everyone has the right to respect for their private and family life, their home and their correspondence."

- ECHR Art. 8 para. 1

Based on this reasoning, the EU Parliament had brought an action against the EU Commission because the binding storage of traffic data for EU citizens violated this regulation.

Protected area

The right to informational self-determination is broad. No distinction is made between whether more or less sensitive data of the individual are affected. The Federal Constitutional Court found that among the processing and linking options of information technology, even an irrelevant date can take on a new significance and there is no irrelevant data in this regard.

Interventions

Limitations to the fundamental right are possible, but they require a legal basis. In doing so, the legislator has to weigh up the confidentiality interest of the person concerned and the public information interest of the processing body.

Restrictions are only permitted in the overriding general interest. They require a legal basis that must comply with the standard of clarity.

A distinction is made between measures that are taken without or against the will of the person concerned and those that are voluntary. For the former, the legal authorization must also be "area-specific, precise and official help-proof" (census ruling, BVerfGE 65, 1 [46]).

In addition, a distinction can be made between anonymized data that do not allow any conclusions to be drawn about the person concerned (e.g. for statistical surveys) and data that can be personalized. In the case of anonymized data, the earmarking is loosened, for data that can be personalized, there is a strict earmarking. Legislators must take measures to prevent data misuse (procedural regulations, data protection officers, ...).

Impact

The right to informational self-determination became the basis for the existing data protection laws such as the Federal Data Protection Act or the state data protection laws and also influenced the development of Directive 95/46 / EC (Data Protection Directive).

The right to informational self-determination has also played a major role in constitutional jurisprudence. So the grid search in North Rhine-Westphalia was declared unconstitutional, provided that it only happens on the basis of a "general threat situation"; ^[3] § 100c and § 100d StPO (the so-called big eavesdropping) had to be supplemented by a catalog of offenses and explicit deletion regulations (BVerfGE 109, 279).

The right not to know is considered a “negative variant of the right to informational self-determination”.

spy

The spying of private data out of a state interest is subject to strict restrictions. According to the principle of legality, there is generally a need for legal regulation and, according to the principles of separation of powers, a judicial order. After a certain period of time, the spied on must also be informed of the process. An intended spying on stock will hardly come into law rank.

Most recently, the Federal Constitutional Court overturned the legal regulations of the State of North Rhine-Westphalia as unconstitutional. ^[5] Clarifications from the Federal Ministry of the Interior are expected for the corresponding federal regulations.

See also: spying on data

agreement

In accordance with the current case law (see above), any linking of personal data for the purposes of third parties requires consent if the legal claim of the parties is not to be restricted. For this purpose, agreements are possible that are made between the parties involved and thus the Document the express consent of those involved. A validity for third parties cannot be achieved by agreement between two parties. Conversely, an agreement between two parties cannot be canceled or rendered ineffective by an agreement with third parties.

In this respect, in connection with new techniques and procedures (technologies), it can be assumed that a violation of the rights of informational self-determination, for example by means of location determination, is technically possible. ^[6] However, to rule out this technical possibility as illegal is not a sustainable position. This is confirmed only by the known facilities of mobile radio technology. ^[7]

Violations

If a company uses recognizable personal data for the person concerned, the person concerned generally has a legal right to information about the storage of this data and the purpose of use of this data. If the storage goes beyond simple address data, the data subject generally has a legal right to have the data stored deleted if he has no contractual relationships with the company (see also: Federal Data Protection Act: Rights of the Data Subject).

If a company becomes a nuisance, for example, through promotions, the person concerned can obtain information in each individual case by means of a letter stating the address. If the company does not provide any information, the person concerned can use legal means to enforce information and deletion by warning from a lawyer or by complaint to the court. The person concerned initially bears the costs.

Information security

• • Allgemeine Schutzziele:
  • ◯ Vertraulichkeit (englisch: confidentiality): Daten dürfen lediglich von autorisierten Benutzern gelesen bzw. modifiziert werden, dies gilt sowohl beim Zugriff auf gespeicherte Daten, wie auch während der Datenübertragung.
  • ◯ Integrität (englisch: integrity): Daten dürfen nicht unbemerkt verändert werden. Alle Änderungen müssen nachvollziehbar sein.
  • ◯ Verfügbarkeit (englisch: availability): Verhinderung von Systemausfällen; der Zugriff auf Daten muss innerhalb eines vereinbarten Zeitrahmens gewährleistet sein.
• • Weitere Schutzziele der Informationssicherheit:
  • ◯ Authentizität (englisch: authenticity) bezeichnet die Eigenschaften der Echtheit, Überprüfbarkeit und Vertrauenswürdigkeit eines Objekts.
  • ◯ Verbindlichkeit/Nichtabstreitbarkeit (englisch: non repudiation): Sie erfordert, dass „kein unzulässiges Abstreiten durchgeführter Handlungen“ möglich ist.^[4] Sie ist unter anderem wichtig beim elektronischen Abschluss von Verträgen. Erreichbar ist sie beispielsweise durch elektronische Signaturen.
  • ◯ Zurechenbarkeit (englisch: accountability): „Eine durchgeführte Handlung kann einem Kommunikationspartner eindeutig zugeordnetwerden.
  • ◯ in bestimmtem Kontext (zum Beispiel im Internet) auch Anonymität

Information (or data) is a valuable asset. Access to these should be restricted and controlled. Only authorized users or programs can access the information. Protection goals are defined to achieve or comply with information security and thus to protect data from intended attacks by IT systems: ^{[1]: 6-11}

• • General protection goals:
  • ◯ Confidentiality: Data may only be read or modified by authorized users, this applies both to access to stored data and during data transfer.
  • ◯ Integrity: Data must not be changed without being noticed. All changes must be traceable.
  • ◯ availability: prevention of system failures; Access to data must be guaranteed within an agreed time frame.
• • Further protection goals of information security:
  • ◯ Authenticity (English: authenticity) describes the properties of authenticity, verifiability and trustworthiness of an object.
  • ◯ Liability / non-deniability (English: non repudiation): It requires that "no illegal denial of actions performed" is possible. ^[4] It is important, among other things, when concluding contracts electronically. It can be reached, for example, using electronic signatures.
  • ◯ Accountability: "An action performed can be clearly assigned to a communication partner.
  • ◯ anonymity in a certain context (e.g. on the Internet)

Every well-planned and implemented IT system can have weak points. The system is vulnerable if certain attacks are possible to circumvent the existing security measures. If an attacker uses a weak point or a vulnerability to penetrate an IT system, confidentiality, data integrity and availability are threatened. For companies, attacks on protection goals mean attacks on real company values, as a rule the tapping or changing of internal company information. Every possible threat is a risk for the company. Companies try to use risk management to determine the probability of damage occurring and the resulting amount of damage.

After a risk analysis and evaluation of the company-specific IT systems, appropriate protection goals can be defined. This is followed by the selection of IT security measures for the respective business processes of a company. This process is one of the activities of IT security management. A standardized procedure is made possible by using IT standards.

As part of IT security management, the selection and implementation of appropriate IT security standards takes place. For this purpose, various standards exist in the area of IT security management. With the help of ISO / IEC 27001 or the IT-Grundschutz standard, recognized rules are used to try to reduce the complexity of sociotechnical systems for the area of IT security management and to find a suitable level of information security.

Importance of information security

In the early childhood of the (personal) computer, computer security meant ensuring the correct functionality of hardware (failure of, for example, tape drives or other mechanical components) and software (correct installation and maintenance of programs). Over time, the demands on computers (Internet, storage media) changed; Computer security tasks had to be organized differently. Thus, the concept of computer security remains changeable.

International and supranational data protection law

United Nations

• „Niemand darf willkürlichen Eingriffen in sein Privatleben, seine Familie, seine Wohnung und seinen Schriftverkehr [...] ausgesetzt werden. Jeder hat Anspruch auf rechtlichen Schutz gegen solche Eingriffe oder Beeinträchtigungen. “

Already the General Declaration of Human Rights, announced on December 10, 1948 by the General Assembly of the United Nations, attached importance to the privacy of people. Article 12 of the human rights declaration states:

• "Nobody may be subjected to arbitrary interference in his private life, his family, his home and his correspondence [...]. Everyone is entitled to legal protection against such interference or impairment. "

Although the declaration was not and is not legally binding and the rights set out in it are exclusively declaratory, it can nevertheless be counted among the forerunners or even the cornerstones of supranational data protection law.

In September 2005, the 27th International Conference of Data Protection and Privacy Officers called on the United Nations to further develop the rights to privacy and data protection as human rights.

Council of Europe

Not least with regard to the recently announced UN human rights declaration, the Council of Europe's European Convention on Human Rights, signed in 1950 and coming into force in 1953, also contained a regulation on data protection - even if the term was not yet in use at that time. According to Art. 8 Para. 1 of the European Convention on Human Rights "everyone has the right to respect for his private and family life, his home and his correspondence". This sentence, which is to be understood in a more declarative and programmatic way, is still valid today; in Germany it has the same rank as a federal law.

After electronic data processing and thus data protection became more and more important in the 1970s, the Council of Europe prepared its own convention on data protection, which was agreed in 1981 as a convention for the protection of people in the automatic processing of personal data. The European Data Protection Convention, as the convention was called colloquially, came into force in 1985. Through the convention, the states that have acceded to it undertake to observe certain elementary data protection principles in automated data processing and to enforce them on their own territory also against third parties.

OECD

In 1980, the Organization for Economic Cooperation and Development (OECD) formulated guidelines for the protection of personal privacy and the cross-border movement of personal data. The guidelines are intended in particular to facilitate cross-border data exchange. they provide However, these are only non-binding recommendations and can now be considered outdated. The OECD recommendations are not of practical importance.

European Union

Until 2000, the data protection law of the European Union was primarily concerned with the creation and strengthening of the common European internal market. Different national data protection laws are seen as possible barriers to trade. Only with the adoption of the Charter of Fundamental Rights of the European Union was data protection recognized as a fundamental right.

Charter of Fundamental Rights

In 2000, the heads of state and government of the EU member states proclaimed the Charter of Fundamental Rights of the European Union. Article 7 of the Charter guarantees everyone "the right to respect for their private and family life, their home and their communication". Art. 8 of the Charter also stipulates a right to protection of personal data. Data protection was thus expressly recognized as a fundamental right at the level of the European Union. The Lisbon Treaty made the Charter of Fundamental Rights binding law for the EU and its member states.

Article 16 (1) of the Treaty on the Functioning of the European Union stipulates that every person has the right to the protection of their personal data.

Today, private and public companies are dependent on IT systems in all areas of their business activities, private individuals in most matters of everyday life. Since, in addition to dependency, the risks for IT systems in companies are generally greater than for computers and networks in private households, information security is primarily the responsibility of companies.

Corresponding obligations can be derived in the entire German-speaking area from the various laws on company law, liability law, data protection, banking law, etc. There, information security is a building block of risk management. Internationally, regulations such as Basel II and the Sarbanes-Oxley Act play an important role.

Criticism of data protection law

The current data protection law can only fulfill its purpose incompletely. Its basic structure is based on the data protection concept of the 1970s, which in turn is based on the electronic data processing of the time. This was characterized by the central data storage on mainframes, limited storage capacities and a relatively small group of - mostly governmental - data processors.

State-of-the-art data protection law has only partially taken into account the technical development of the past 30 years and with considerable delay. Technical innovations that can impair data protection - for example the Internet, video surveillance, biometrics, RFID - are not regulated by law or are only insufficiently regulated. Numerous amendments to the law have been unable to change this.

In addition, German data protection law is considered to be "over-regulated, fragmented, confusing and contradictory" (Alexander Roßnagel). Today, even experts can no longer see data protection law in its entirety. In addition, there is a "massive enforcement deficit in data protection" (Johann Bizer): Violations of data protection regulations usually have no consequences because the data subjects generally have no knowledge of improper data processing and the state data protection authorities do not have the necessary human resources to deal with them Control data processors effectively.

Cybercrime

Cybercrimes are crimes that are based on the Internet or are done using the techniques of the Internet. This should not be confused with computer crime, where primarily the computer is used as a weapon, even without using the Internet. Protection against cybercrime is also called online security. This term is to be distinguished from internet security, which also includes the protection of the infrastructure belongs itself, including protection against criminal offenses against the Internet itself, online or material, but also against other dangers, as part of IT security.

Manifestations

The manifestations are very diverse; Examples include Internet fraud, spying on data, violations of the distribution ban or the protection of minors in the media, identity theft, copyright infringement, cyber terrorism, cyberbullying, sedition and the spread of child pornography.

The transition to cyberwar methods and procedures (“net war”) has become fluid; in individual cases it is by no means easy to determine whether an attack on the Internet serves relevant criminal purposes or is intended militarily or politically (e.g. in the event of extensive sabotage of the highly ITC-dependent financial system or the websites of public institutions in the broadest sense). According to the observations, the “malware industry” is becoming increasingly professional, and attacks on computers and computer networks are becoming increasingly sophisticated. ^[1]

According to antivirus software developers, z. For example, the infection of computers with malware used for identity theft (such as spying on bank account data) by 800 percent from the first to the second half of 2008. ^{[2] [3]}

In the banking sector, in addition to online attacks on the accounts of private customers, attacks on interbank business with the help of counterfeit versions of payment orders are increasing. The malware used thereby penetrates the network of connected institutes and causes damage of tens of millions of dollars annually. ^[4]

The CEO Fraud's target is companies that were cheated by over $ 740 million according to a 2015 FBI statement. ^[5]

Technical progress

Almost since the general establishment of the Internet since the 1990s and the increasing electronization of further fields of public life, especially in the economic field, criminals and security experts have been competing in rabbits and hedgehogs in a wide variety of fields, most of which so far a "positive stalemate" for security. In recent times (2010s) the methods of cyber criminals have become increasingly sophisticated and elaborate (which also applies to many virus programmers, for example, whose products have meanwhile reached an astonishing, frightening technical level in individual cases ^{[6] [7]} ).

According to the US telecommunications service provider Verizon Business, criminals in the United States have managed to crack the encryption when transmitting PIN codes. The hackers were able to get both encrypted and unencrypted PINs. According to media reports, experts believe that the problem can only be solved if the financial industry overtakes electronic payment transactions as a whole. ^[8th]

Situation in Germany

For its 2014 report on the cost of cybercrime sponsored by HP Enterprise Security, the Ponemon Institute surveyed a representative cross-industry sample of 46 companies in Germany. The survey showed an average loss of € 6.1 million, with a range of € 425 thousand to € 20.2 million per year. Phishing, social engineering and web attacks accounted for more than 35% of the costs. ^[9]

The Federal Criminal Police Office (BKA) opened in 2012 Germany 229,408 Criminal offenses to which the characteristic “Internet crime scene” applied. ^[10]

According to the BKA, "phishing" continues to be a focal point in the area of cybercrime in view of the existing damage potential and the lucrativity for the perpetrators, despite a 46% drop in the number of cases. "The BKA claims to have identified almost 3,500 cases in 2012, with an average amount of damage of approximately 4,000 euros per case. User awareness, increased protective measures and effective IT management are held responsible for the decline. ^[11]

Smartphones are still an interesting target for criminals. Users are increasingly using these, such as B. for online banking, authorization of transactions, direct access to e-mail accounts and accounts of social networks or even for the use of business data and are insufficiently aware of the mobile operating systems. ^[12]

The number of crimes committed using the Internet as a crime tool increased slightly in 2016. In 2016, a total of 253,290 cases were recorded compared to the previous year (244,528 cases). These include crimes such as commodity and merchandise credit fraud, computer fraud, performance and performance credit fraud, the spread of pornography and criminal offenses against copyright regulations. As the police infographic shows, fraud alone accounted for 27.8 percent of cases; The 20.7 percent share in commercial credit fraud is also noteworthy. Merchandise and merchandise credit fraud make up almost half of all cases. Of the 101,654 suspects, 68.7 percent were male and 31.4 percent female. The clearance rate was 65 percent. ^[13] Police crime statistics also showed a significant increase in copyright infringements in 2007: by 54.6 percent to 32,374 cases. Above all, the tightening of the music industry's action against illegal downloading of copyrighted data was held responsible. ^[14]

There is an increase in fraudulent faceshops on online platforms where paid goods are not delivered or are not delivered in the quality ordered. The police crime statistics for 2015 show almost 75,000 cases of goods fraud on the Internet for Germany. The German Federal Criminal Police Office calls this a "mass phenomenon that presents law enforcement authorities with major challenges". ^[15]

According to a BITKOM study, almost four million Germans had been victims of computer or internet crime by mid-2008. Seven percent of all computer users aged 14 and over have already suffered financial damage from viruses, online auctions or data misuse during online banking. The low level of security awareness among users was nevertheless complained about. ^[16] In its report presented at CeBIT The Situation of IT Security in Germany in 2009, the Federal Office for Information Security (BSI) expressed its concern about the growing cybercrime; the situation was assessed as "extremely serious" and "worse than feared". ^[17]

The worry-free handling of data in the "interactive" applications of the web, especially in the increasingly popular social networks, is particularly alarming for security experts. “Without hesitation, users reveal detailed private information in their user profiles. They often forget that information on the Internet is accessible to practically everyone and will remain so, ”says the BSI study.

Botnets, by means of which cyber criminals often network and abuse hundreds of thousands of hijacked private and office computers without user knowledge, according to the BSI "part of a professional and international shadow economy", have meanwhile become an outstanding threat. A number of prominent discoveries have been made since 2007 (see GhostNet; Trojans). ^[18]

In a recent Forsa survey published on behalf of Schufa in 2018, 39 percent of those surveyed stated that they themselves had been victims of cybercrime before, 12 percent specifically suffered abuse of identity on the Internet. ^[19]

Combating cybercrime

Due to the significantly increased dangers, the European Commission therefore presented a five-point plan for protecting critical information infrastructures in the member states of the European Union at the end of March 2009. ^[20]

• • Prävention und Abwehrbereitschaft
• • Erkennung und Reaktion; Einrichtung eines Frühwarn- und Informationsnetzes
• • Folgenminderung und Wiederherstellung
• • Internationale Zusammenarbeit
• • Aufstellung von einheitlichen Kriterien für europäische kritische IKT-Infrastrukturen

In addition to forced coordination between the member states, it provides:

• • Prevention and preparedness
• • detection and response; Establishment of an early warning and information network
• • Mitigation and recovery
• • International cooperation
• • Establishment of uniform criteria for European critical ICT infrastructures

According to the EU Commission, the European Network and Information Security Agency (ENISA) is to push ahead with the initiative. The Commission would also work with Member States to “develop a roadmap to promote principles and guidelines at global level. Strategic cooperation with third countries is promoted as a means of building global consensus, especially in the dialogues on information society issues. " ^[21]

Convention on Cybercrime (Cybercrime Convention)

Already on November 23, 2001, the 26 countries of the Council of Europe signed the "Convention on Cybercrime" in addition to the USA, Canada, Japan and South Africa, also called "Budapest Convention against Data Network Crime" or Cybercrime Convention ^[22] for short, in order to harmonize the country-specific computer criminal law regulations . Among other things, internet users or domain owners are to be identified across borders, or websites whose content violates the convention can be removed from the network across borders. Rights of unsuspecting third parties are not separately protected. Racist or xenophobic content is not taken into account at the US request with reference to freedom of expression. The agreement also represents "a landmark in the Council of Europe's treaty system to combat terrorism and organized crime" (Hans Christian Krüger, then Deputy Secretary General of the Council of Europe).

An around the clock international contact network for quick administrative assistance has been set up.

Germany

In order to combat cyber crime, the Technical Service Center for Information and Communication Technologies (TeSIT) was set up at the Federal Criminal Police Office in Germany, whose primary task, according to the Interior Ministry, is to "provide technical support for executive measures and investigations in data networks". The TeSIT is also assigned to the central office for start-up research in data networks (ZaRD) set up in early 1999. According to the Federal Criminal Police Office, it evaluates the Internet "around the clock, systematically and independently of police-relevant content - especially child pornography - and carries out the gathering, securing and documenting of evidence if necessary". Reference is made to "a considerable number" of search results. It is also emphasized that "the police have to keep up with the rapid technical development". ^[23] In the persecution, however, it is a major problem that perpetrators can act globally, but authorities are only limited nationally and regionally. ^[24]

The police in the individual federal states are also involved in the fight against cybercrime. For example, there has been a “Central Office for Internet Crime” with 20 employees at the Lower Saxony State Criminal Police Office since 2009.

The Bund Deutscher Kriminalbeamter (BDK) and the Stiftung Deutsches Forum für Kriminalprävention (DFK), with the support of representatives from research and business, presented the Federal Government with a ready-made and immediately implementable concept for more security on the Internet in June 2009. ^[25] It is the online offer Web Patrol under the motto The 8th sense on the net. The reason for this is unfiltered Internet access with content such as pornography, pedophilia, Islamism, right and left-wing extremism, terrorism, which are freely available for children and adolescents. Web Patrol includes an information portal that is intended to provide target-group-oriented information on questions of security and behavior and a program that is able to report suspicious content directly. By simply clicking an additional button in the browser, Internet users should use an automatically generated message to send knowledge about suspicious content, questionable activities, data theft, attacks in chat rooms and criminally relevant material to an independent clearing house, which is made up of an interdisciplinary team of criminalists, psychologists and sociologists composed, can transmit. This evaluates incoming reports, provides initial feedback and forwards the process to the responsible institutions. ^[26] As the Internet increasingly as a medium The BDK demands that the model be used before the next legislative period, for the preparation and execution of deviant behavior up to the execution of criminal acts, and non-sensitized persons become an easy victim for cybercriminals or even stimulated by the possibilities of the internet for criminal acts to implement. ^[27]

Computer crime

The term "computer crime" or "cyber crime" encompasses "all crimes that are committed using or against the information and communication technology (ICT)". ^[1]

definition

There is no generally applicable definition of the term computer crime. Usually all criminal offenses are summarized, which are committed using or against the information and communication technology. In the police field, a distinction is also made between computer crime in the narrower sense and computer crime in the broader sense. ^[2]

• • Computerkriminalität im engeren Sinne, für diese Straftaten wird lediglich ein Computer mit oder ohne Internetnutzung als Tatwaffe eingesetzt
• • Internetkriminalität, diese Straftaten basieren auf dem Internet oder geschehen mit den Techniken des Internets

Cybercrime can be divided into:

• • Computer crime in the narrower sense, for these crimes only a computer with or without internet use is used as a weapon
• • Internet crime, these offenses are based on the Internet or are done using the techniques of the Internet

The distinction is that cybercrime also includes many crimes and crimes that would be possible without the Internet (including the distribution of prohibited content, harassment), while cybercrime in this sense specifically refers to the context of electronic data.

According to the German Federal Criminal Police Office (BKA), cybercrime in the narrower sense refers to “special phenomena and forms of this form of crime in which elements of electronic data processing (EDP) are essential for the execution of the crime”. ^[3]

The term computer crime in a broader sense is used colloquially in Germany for acts related to computers, which are not criminal offenses, but are illegal acts. The assignment to the respective areas depends in particular on whether there are relevant penal regulations at the relevant crime scene.

to form

• • Ausspähen, Abfangen von Daten einschließlich Vorbereitungshandlungen
• • Computerbetrug, Betrug mit Zugangsberechtigungen zu Kommunikationsdiensten
• • Computersabotage
• • Datenveränderung
• • Fälschung beweiserheblicher Daten
• • Täuschung im Rechtsverkehr bei Datenverarbeitung (§ 270 )

Cybercrime in the narrower sense includes the Cybercrime Federal Situation Report 2011 of the German Federal Criminal Police Office: ^[4]

• • Spying on, intercepting data including preparatory actions
• • Computer fraud, fraud with access rights to communication services
• • Computer sabotage
• • Data change
• • Falsification of evidence-relevant data
• • Deception in legal transactions in data processing (§ 270)

The Austrian Federal Criminal Police Office almost also includes crimes in which attacks on data or computer systems are carried out using information and communication technology (e.g. data corruption, hacking, DDoS attacks).

• • alle Ausprägungen digitaler Erpressung
• • Urheber- und Markenrechtsverletzung
• • unerlaubte Veranstaltung eines Glücksspiels
• • der Vertrieb verbotener Substanzen
• • der Austausch von kinderpornographischen Darstellungen oder Gewalt verherrlichender Propaganda oder
• • die Verletzung des höchstpersönlichen Lebensbereichs durch Bildaufnahmen
• • die onlinebasierte Anbahnung eines sexuellen Missbrauches von Kindern - dem sog. Cyber-Grooming

In Germany, computer crime in the broader sense includes all crimes where IT is used for planning, preparation or execution. These now extend to almost all areas of crime in which the internet is used. For example:

• • all forms of digital extortion
• • Copyright and trademark infringement
• • unauthorized organization of a game of chance
• • the distribution of banned substances
• • the exchange of child pornography or violence glorifying propaganda or
• • the violation of the very personal area of life by taking pictures
• • the online-based initiation of child sexual abuse - so-called cyber grooming

These crimes are not registered under the term cybercrime in police crime statistics (PKS), but with special PKS key numbers. ^[5]

In Austria, crimes of computer crime are understood in a broader sense, crimes in which information and communication technology is used to plan, prepare and execute conventional criminal offenses, such as fraud, child pornography and cyberbullying.

Case numbers in Germany

According to the BKA situation report, a total of 63,959 cases of cybercrime in the narrower sense were recorded in 2012.

Cases of computer fraud (24,817) fell 7.13% compared to 2011, and “fraud with access to communication services” (2,952) decreased by around 38% in 2012. There has been an increase of around 11% in the offenses "falsification of evidence-relevant data, deception in legal transactions in data processing" (8,539). While the "crimes by spying on, intercepting data, including preparatory actions" accounted for 16,794 cases. Offenses "data changes / computer sabotage" (10,857) increased by almost 140% compared to 2011.

With a share of around 39%, computer fraud is the largest crime group of all cases shown in the situation picture. ^[6]

Computer crime in a broader sense also includes cybercrime, in addition to the criminal cases subsumed under cybercrime. The importance of the Internet as a tool is shown by the fact that, with 229,408 cases, cybercrime has almost 10 times as many cases as cybercrime in the narrower sense. Phishing in connection with online banking alone caused a total loss of € 13.8 million in 2012. ^[7]

Cybercrime has already lost 2/3 of German companies' company secrets. This puts Germany in second place behind the USA and ahead of France. ^[8th]

Situation in Switzerland

With the ratification of the Council of Europe Convention on Cybercrime, Switzerland is participating in the increased international fight against computer and cybercrime. The convention entered into force for Switzerland on January 1, 2012. At the same time, the Federal Council enacted the necessary legislative changes. The offense of unauthorized intrusion into an electronic data processing system (EDP) ("hacking", Art. 143 to 147 Swiss Criminal Code) now lies in the area of criminal liability. Also making the access and circulation of passwords, programs and other data punishable if the person concerned knows or has to assume in good faith that they can be used for the illegal intrusion into a protected computer system (see hacker paragraph , based on Germany § 202c German Penal Code).

In Switzerland, it is the Swiss Coordination Center for Combating Internet Crime (KOBIK) which keeps statistics on prosecuted computer crimes and publishes them in an annual report. The latest statistics for the 2012 financial year were published in May 2013. ^[9] 8242 reports were submitted via the online form on the website, an increase of 55% compared to the previous year. For the first time in the history of KOBIK, the number of Reports of offenses against the property (3260 reports) those of reports of criminal acts against sexual integrity (3083 reports). Offenses against life and limb (99 reports) and offenses against public peace (85 reports) were committed to a much lesser extent. It should be noted that the reports received are of good quality with 80% criminal relevance.

Situation in Austria

In 2013, the Austrian Federal Criminal Police Office recorded 11,199 reported cybercrime cases. 17.8% were resolved. 421 cases of this concern misuse of data processing with the intention of enrichment, including commercial fraudulent misuse of data, in which data is entered, changed, deleted, suppressed or otherwise disturbed in the data processing process (§ 148a StGB). These paragraphs also include phishing and malware attacks. The functionality of a computer system in accordance with Section 126b of the Criminal Code was disrupted and reported in Austria in 470 cases in 2013. DDoS attacks also fall under these paragraphs. The illegal access to computer systems is regulated in Austria in § 118a StGB. In 2013, 391 cases were reported. ^[10]

45.6 percent of the suspects are between 26 and 40 years old, 26.9% of the suspects are over 40. 58.3 percent of the perpetrators were from Austria. 468 suspects were found in Germany, 373 in Serbia, 176 in Nigeria.

Attempts are being made to professionalize the work on combating computer crime in Austria in order to counter the increasing professionalization of the perpetrators. Therefore, a Cybercrime Competence Center ( C4 ) set up. Investigators and IT forensics are sent on international training courses, such as the International Association for Computer Information Systems (IACIS) and the European Cybercrime Training and Education Group (ECTEG). In summer 2013, the FBI arrested 19 suspected hackers as part of Europol's BlackShades operation. ^[11]

Damage

According to the situation picture, only the damage amounts for the crimes "computer fraud" and "fraud with access rights to communication services" are recorded in the German crime statistics (PKS).

This damage rose by around 16% in 2011 to around EUR 71.2 million (2010: EUR 61.5 million). In 2011, around EUR 50 million of this related to computer fraud and around EUR 21.2 million to fraud involving access data to communication services. ^[5]

The BKA has calculated an average damage amount for phishing in the online banking area: for 2011 around 4,000 euros per case and a total of 25.7 million euros. If one compares the calculated (approximate) damage sum with that of 15.7 million euros for 2007, there is an increase of 35%. In view of the "existing damage potential and the lucrativity for the perpetrator side", phishing "continues to be a focus in the field of cybercrime" ^[12] (meaning: computer crime in a broader sense - the author).

The creation of a Europe-wide "European cybercrime platform" is one of the fields of action of the "Digital Agenda". ^[13]

According to Symantec, Germany (2012) is “No. 1 in Europe with damage caused by malicious software of EUR 24 billion”; “Damage of 284 billion euros was incurred worldwide,” says security manager Orla Cox from Symantec, Dublin. ^[8th]

Countermeasures

In various countries, special police units have been commissioned to combat computer crime. Europol has set up its own department for coordinating cooperation since 2013, the European Center for Combating Cybercrime (EC3). ^[14] In Germany, so-called Central Contact Points Cybercrime (ZAC) have been set up at the State Criminal Police Offices and at the Federal Criminal Police Office since 2014. ^[15]

Darknet

Darknet (English for "dark network") describes in computer science a peer-to-peer overlay network, the participants of which manually establish their connections with each other. This concept is in contrast to conventional peer-to-peer networks, in which the connections to the clients of strangers are usually initiated automatically and arbitrarily. As a result, a darknet offers a higher level of security, since an attacker cannot easily access the network - or ideally knows nothing about the existence of the network. In order to integrate new people into a darknet, they usually have to be invited or accepted by participants. In places, this is only possible for participants who have privileges.

overview

The data is often encrypted and transmitted. Their application ranges from normal data exchange between private individuals via small exchange networks for music and films to networking with regime critics. ^{[1] [2]} To the charge of use to counter example for copyright infringement through music exchange, is emphasized by darknet operators, that freedom of expression can be strengthened, especially in countries such as China censorship by such networks.

Way of working

The entry into the Darknet with the Tor Browser

If the network is used for file sharing, Darknet refers to a type of friend-to-friend network (F2F). Most file sharing programs are not darknets because the nodes (peers) can communicate with every other node (public, untested peers) in the network.

A friend-to-friend network differs from a darknet in that a friend-to-friend network also supports the forwarding of files to friends of friends, but the friends' IP addresses are not visible to friends. An F2F network must therefore be organized decentrally (you know the IP addresses of the friends, but not their friends), a darknet can also be organized centrally (that is, a hub with all friends could also be a darknet; however, here you know all the IP addresses of all).

Perhaps the best known darknet software is WASTE from Nullsoft. A real F2F network can be set up using the Instant Messenger Turtle F2F, which also allows file sharing via the client giFT. As a participant - unlike WASTE in broadcasting mode - you do not know the friends of the friends. A turtle network is thus founded in Turtle, in which only connections that come from certified friends can be established. However, Turtle does not seem to be developing any further, but similar approaches are also being followed by RetroShare, HybridShare, OnShare, ExoSee, GigaTribe or Gazzera.

Freenet, a network for anonymous and censorship-free information exchange, is working from version 0.7 to create a global darknet that can have millions of participants. Such an atypical darknet should be possible through the application of the small world phenomenon.

Conceptual history

Already in the 1970s the term darknet was used to describe networks isolated from ARPANET ^[3] and was further popularized by the article The Darknet and the Future of Content Distribution from 2002. ^[4] Four Microsoft employees argue that the existence of darknets is the main obstacle to the development of working techniques for digital rights management.

reception

Due to the properties of the Darknet, there are considerable opportunities for criminal actions, such as illegal drug or arms trafficking. More recent criminal investigations have been carried out. ^[5] A study published in early February 2016 by the British think tank International Institute for Strategy Studies ^[6] classified 57 percent of 5205 active pages examined in the Darknet as "illegal". However, over a third of the offers would be used legally, including hidden services such as those from Facebook or Mailbox.org. ^{[7] [8]} Constanze Kurz, spokeswoman for Chaos Computer Clubs (CCC) criticized a one-sided view of the mass media on the Darknet on netzpolitik.org; For example, "encrypted networks would be used by journalists, human rights organizations, whistleblowers, or people who need to protect themselves for other reasons." ^[9] CCC spokesman Linus Neumann said: "The darknet is the Internet as it is would actually wish for. A network without censorship and surveillance, with all its advantages and disadvantages ”. The debate in Germany about darknet crime also shows that one lives in a relatively free society. "In a country like China, you land faster in the darknet because you have to protect your communication more." The managing director of the human rights organization Reporter Without Borders (ROG), Christian Mihr, refers to the communication via darknet in countries like Syria or Iran. However, the Darknet would also be relevant for Germany, since "the Internet [...] is also being monitored more and more here". With increasing surveillance, "the number of those who learn to appreciate the anonymity of darknets increases." One has the right to "anonymous communication", and equating crime and darknet is "extremely dangerous". ^[10]

The darknet is also of particular importance for whistleblowers. In this regard, important newspapers such as the New York Times have already set up pages on the darknet in order to be able to receive confidential information anonymously. ^[11] The Telegram Messenger belongs to the Darknet due to its features with encryption ^[12] and after the prohibition of territories in different countries. ^[13] Because of the anonymity it contains encrypted channels for the sale of banned substances, the recruitment of various organizations and the coordination of anti-government activities.

peer to peer

Peer-to-peer model

Peer-to-peer (P2P) (from English peer "equal", "peer") and computer-computer connection are synonymous terms for communication between equals, here related to a computer network. In some contexts one also speaks of cross communication.

In a pure peer-to-peer network, all computers have equal rights and can both use services and make them available. In modern P2P networks, however, the network participants are often divided into different groups depending on their qualifications, which take on specific tasks. The core component of all modern peer-to-peer architectures, which are usually already implemented as an overlay network on the Internet, is therefore a second internal overlay network, which usually consists of the best computers in the network and the organization of the other computers and the Provision of the search function takes over.

With the search function ("lookup") peers in the network can identify those peers who are responsible for a specific object identifier (Object-ID). In this case, responsibility for each individual object is firmly assigned to at least one peer, which is why we speak of structured overlays. Using the search operation, the peers can search for objects in the network that meet certain criteria (e.g. file or buddy name match). In this case there is no assignment structure for the objects in the P2P system, one speaks of unstructured overlays.

As soon as the peers holding the searched objects have been identified in the P2P system, the file (in file exchange networks) is directly, i.e. H. from peer to peer. There are different distribution strategies, which parts of the file should be downloaded by which peer, e.g. B. BitTorrent.

The opposite of the peer-to-peer model is the client-server model. With this, a server offers a service and a client uses this service. This role allocation is removed in peer-to-peer networks. Each participant is a peer because he can use a service equally and offer it himself.

Characterization of peer-to-peer systems

• • Peers weisen eine hohe Heterogenität bezüglich der Bandbreite, Rechenkraft, Online-Zeit, ... auf.
• • Die Verfügbarkeit und Verbindungsqualität der Peers kann nicht vorausgesetzt werden („Churn“).
• • Peers bieten Dienste und Ressourcen an und nehmen Dienste anderer Peers in Anspruch (Client-Server-Funktionalität).
• • Dienste und Ressourcen können zwischen allen teilnehmenden Peers ausgetauscht werden.
• • Peers bilden ein Overlay-Netzwerk und stellen damit zusätzliche Such-Funktionen zur Verfügung.
• • Peers haben eine signifikante Autonomie (über die Ressourcenbereitstellung).
• • Das P2P-System ist selbstorganisierend.
• • Alle übrigen Systeme bleiben konstant intakt und nicht skaliert.

Typical but not necessary characteristics of peer-to-peer systems are:

• • Peers are highly heterogeneous in terms of bandwidth, computing power, online time, ...
• • The availability and connection quality of the peers cannot be assumed ("churn").
• • Peers offer services and resources and use the services of other peers (client-server functionality).
• • Services and resources can be exchanged between all participating peers.
• • Peers form an overlay network and thus provide additional search functions.
• • Peers have significant autonomy (via the provision of resources).
• • The P2P system is self-organizing.
• • All other systems remain intact and not scaled.

(after: Steinmetz, Wehrle 2006)

Types of peer-to-peer systems

P2P systems can be divided into unstructured and structured P2P systems.

• • Zentralisierte P2P-Systeme (Beispiel: Napster), welche einen zentralen Server zur Verwaltung benötigen, um zu funktionieren
• • Reine P2P-Systeme ohne zentrale Instanz (Beispiele: RetroShare, Gnutella 0.4, Freenet) Eine spezielle Art eines reinen, dezentralen Netzwerkes bildet das friend-to-friend- oder Web-of-Trust-Netzwerk, bei dem keinerlei Verbindungen zu unbekannten IP-Adressen unterhalten werden, sondern ausschließlich Verbindungen zu Freunden (trusted friends) etabliert werden.
• • Hybride bzw. Hierarchische P2P-Systeme, welche dynamisch mehrere zentrale Server („Superknoten“) zur Verwaltung bestimmen (Beispiele: Gnutella 0.6, Gnutella2 (G2), JXTA)

Unstructured P2P systems are subdivided according to the type of their construction. One differentiates:

• • Centralized P2P systems (example: Napster), which require a central server for administration in order to function
• • Pure P2P systems without a central instance (Examples: RetroShare, Gnutella 0.4, Freenet) A special type of a pure, decentralized network is the friend-to-friend or web-of-trust network, which has no connection to unknown IP - Addresses are maintained, but only connections to friends (trusted friends) are established.
• • Hybrid or hierarchical P2P systems, which dynamically determine several central servers ("super nodes") for administration (examples: Gnutella 0.6, Gnutella2 (G2), JXTA)

Centralized and pure P2P systems are referred to as first generation systems, while decentralized systems are referred to as second generation systems. Systems that pass files over non-direct connections are third generation systems. See also the term file sharing in detail.

Structured P2P systems often use a distributed hash table (DHT). In structured systems, searches can therefore be answered from a distributed index.

Standardization and the future

The future of peer-to-peer technology will primarily depend on whether it is possible to define a standard - a kind of platform technology that enables further applications to be set up.

JXTA is one such standard that was heavily supported by Sun Microsystems and is open source. Sun manufactured the most extensive and stable reference implementation currently.

Gnutella is another open standard that has been extensively tested, but has so far been used almost exclusively for file distribution and decentralized file searching.

In addition, it is conceivable that the network transmission performance will increase similar to the computing power of the PCs, so that there is the possibility that a peer can still know the "next but one" peer and that the visibility of a peer via databases and other peers can continue to increase.

Overlay mesh

Example of an overlay network

• • (logisches) Netz oberhalb existierender Infrastruktur
• • oftmals eigener Adressraum mit eigener Adressierung (unabhängig vom Underlay)
• • ggf. Einsatz eigener Wegewahlverfahren

An overlay network is a computer network that is based on an existing network (called an underlay). The main features of an overlay network are:

• • (Logical) network above existing infrastructure
• • often own address space with own addressing (independent of the underlay)
• • Use of your own routing procedures if necessary

The overlay network is therefore used to set up an additional topology (physical, logical, structural, ...). With the newly created structure, for example, current technologies such as IPv6 can be tested or alternative routes can be created for the data. Peer-to-peer networks, such as Gnutella and Chord, are also based on an overlay network structure, which, for example, makes efficient searching and a certain network coordination possible. Additional overlays can also be placed on these overlays, e.g. B. for monitoring the P2P overlay, SkyEye is used, which introduces its own address space and brings its own protocols that require the functionality of the P2P overlay.

In the beginning, the Internet was an overlay network over the existing telephone network. This is partly the case today, as there are still users who connect to the Internet via modem. In the meantime, however, the telephone network is increasingly becoming an overlay network that is based on the Internet.

• • Content Addressable Network (CAN)
• • Chord
• • DiffServ (separiert physikalisches Netz in mehrere logische durch Einteilung der Netz-Ressourcen in verschiedene Dienstklassen)
• • Freenet
• • Gnutella, Gnutella2
• • GNUnet
• • I2P
• • Kademlia
• • Lightning Netzwerk (Virtualisiert den Informationsaustausch über verschiedene Blockchain-Netzwerke durch Atomic Swaps)
• • RetroShare
• • MBone, 6Bone, ABone
• • P-Grid
• • Pastry/Tapestry
• • PNRP
• • RON
• • Tor
• • XBone
• • SkyEye

Some examples of overlay networks are:

• • Content Addressable Network (CAN)
• • Chord
• • DiffServ (separates the physical network into several logical ones by dividing the network resources into different service classes)
• • Freenet
• • Gnutella, Gnutella2
• • GNUnet
• • I2P
• • Kademlia
• • Lightning network (virtualizes the exchange of information via various blockchain networks through atomic swaps)
• • RetroShare
• • MBone, 6Bone, ABone
• • P-grid
• • Pastry / tapestry
• • PNRP
• • RON
• • Goal
• • XBone
• • SkyEye

Iris detection

Iris detection is a method of biometrics for the purpose of authenticating or identifying people. For this purpose, images of the iris (iris) of the eye are recorded with algorithms, the characteristic features of the respective iris are identified using algorithmic methods, converted into a set of numerical values (feature vector, “template”) and used for recognition by a classification algorithm such as . B. stored a neural network or compared with one or more templates already stored.

The currently most widespread method and template (as of April 2007) in commercial use is the iris code based on algorithms by the mathematician John Daugman.

Commercial detection methods record around 260 individual optical features of the iris. These characteristics develop from a randomly controlled, morphogenetic process in the first months of a person's life and remain largely unchanged over the remaining lifetime. Even identical twins do not have an identical iris structure. The outstanding property of iris recognition in practical use is its extremely low number of false positives compared to other biometric methods Comparative results (“false matches”), ie the probability of confusing an iris code with that of another person's eye is almost zero. As a result, iris recognition is suitable as a reliable identification procedure even in large databases with millions of personal data records, and for identification in access control situations without a primary identification feature, i.e. without ID cards or RFID tags.

The Irisscan is a scientifically recognized, safe method of identifying a person.

Another characteristic is the low need for computing resources for the iris comparison. Therefore, iris detection and recording is particularly suitable for mobile use in PDA-sized devices.

False negative results (`` false non-matches ''), i.e. cases of a person actually not being recognized, can occur in particular under unfavorable conditions of the eye, for example if the iris is due to the edges of the glasses, reflections on the glasses or those of largely East Asians ( or Far East Asians) typical narrow eyelids is only insufficiently visible.

This would include a record of all people residing in the EU in order to be able to assign them a unique personal identification number for governmental and legal business purposes. The iris recognition would make it possible to identify and avoid multiple or incorrect identities.

Applications already exist in access control to high security areas and in automated border controls (e.g. Frankfurt, Schiphol, Heathrow airports).

In the first mass application in immigration control in the United Arab Emirates in 2002, illegal immigrants tried to avoid being identified by Irisscan. With the help of medical eye drops, the pupil dilates and the iris contracts so that recognition is temporarily prevented. The system was then changed so that an extended iris is automatically recognized as such and the iris scan is repeated on the person after a few hours.

Together with face and fingerprint recognition, iris recognition is one of the biometric forms provided by the ICAO for use in electronic passports (ePassport). In order to ensure worldwide, manufacturer-independent interoperability of the data, the standard ISO / IEC 19794-6 "Exchange format based on iris images" specifies the requirements for iris image acquisition and storage that apply to this.

Iris detection is only suitable for forensic purposes to a limited extent, since its iris structures disintegrate just a few minutes after a person has died.

In mobile phones, iris recognition is used to unlock the phone instead of a PIN code or a fingerprint. This technology was first used in the Fujitsu ARROWS NX F-04G. ^[8] Microsoft's Lumia 950 series mobile phones also use this authentication technology.

In May 2017, the Chaos Computer Club demonstrated how easy it is to overcome iris detection on the Samsung Galaxy S8. First you have to take a photo of the face of the Galaxy S8 owner with a commercially available compact camera. Because the iris scanner works in the infrared range, the camera must be put into night mode. The eye is then digitally enlarged and the photo printed out with a laser printer. Now you put a contact lens on the printout, the fake eye is ready for a few euros. The eye gains plasticity through the contact lens, so the iris scanner can be tricked.

In the upcoming flagship generation around the Galaxy S9, the technology for iris recognition will be greatly improved. Higher resolution and better software for faster detection are the cornerstones for Samsung developers.

Biometric unlocking methods have become a quasi-standard in smartphones in recent years, especially the fingerprint sensor. Samsung has also been offering the recognition of the iris as an alternative method in its top models since this year. This is exactly where the group wants to implement improvements. According to a report by the Korea Herald, Samsung wants to increase the resolution for the iris scanner from 2 megapixels to 3 megapixels in order to be able to reproduce finer details in the eye and the iris.

One reason for the targeted further development is, according to Samsung's own statement, the leading role in the area of biometric authentication for banking transactions.

Faster and more reliable detection of the iris are a goal for the Galaxy S9 Samsung also expects the improved lens to deliver accurate results, even if the user wears glasses that can inevitably lead to reflections. Even movements of the eyeball should be able to cope with the optimized iris detection of the Galaxy S9 (Plus) considerably better than the current generation.

In addition to the resolution of the image for recognizing the iris, the technicians especially want to massively increase the speed. In addition, iris detection in the dark is on the list of things that need to be optimized and improved.

However, the hardware is only part of the big picture - the software also plays a crucial role. Samsung also wants to improve significantly in this regard in order to make detection faster, more accurate and, above all, more secure. The report did not give specific details.

How an iris scanner works: iris scans are used for identification, particularly in medicine and pharmaceuticals. Special cameras record the iris and store the pattern in the system. Samsung uses an extra built-in camera and infrared light for the Galaxy S7 Edge. It is said to be particularly suitable because it can capture the pattern of the iris very clearly. Visible light or RGB images are more susceptible to influences from ambient light. It is easier to lose details. With the Samsung mobile device, the iris information is encrypted and stored on the Knox platform directly on the device.

Detection: In order to log on to the device again, the camera reads the iris information at a specified distance between the device and the eye and compares it with the stored data. The process should go very quickly and work even in poor light, since the radiation from the display is used for data acquisition.

Other access mechanisms and security: Microsoft offers Hello with Windows 10 facial recognition, which the user can use to log on to the system. The method requires a depth camera that also detects the distance to the camera from the pixel. The Realsense camera from Intel and the manufacturer's Kinect system are certified. In contrast to the integrated iris scanner, you have to purchase extra hardware here.

password

A password, password, also passphrase, keyword code word (also code word), slogan, slogan or slogan (from Italian la parola, the word ‘) is used for authentication. For this purpose, a string of characters is agreed and used, through which someone, usually a person, identifies themselves and thereby confirms their own identity.

In addition to the role of identifying people, passwords are also used to prove certain authorizations: Anyone who knows the password (the correct code) is considered authorized. Examples: slogan for the military or an access code to open doors.

The authenticity of those who identify themselves in this way is only maintained for as long as the password remains secret, that is, it is not known to third parties. The relationship between the password and its user must be established and checked separately (for example by the bank using the postal route, which is particularly protected against manipulation).

A personal identification number (PIN) is a password that usually consists of only digits.

Frequent use of passwords takes place in the computer / internet world in connection with a user name. Here the password is a user-selected or an automatically generated, mostly alphanumeric string.

Passwords are used in numerous areas, for example as an element of parental controls to prevent children from accessing televisions, receivers or unsuitable program content.

Disadvantage: Password chaos due to new, changed and forgotten passwords.

One-time passwords can only be used for authentication once and are then invalid. So there is no harm if the password is spied on during authentication. Traditionally, several one-time passwords are set in advance and noted in the form of a list that must be kept safe. Such one-time passwords are used, for example, as transaction numbers (TAN) in online banking. However, they can also be generated just before they are used, including the time and a PIN, and can only be used within a few minutes.

The password should be long enough so that it cannot be determined by trying it out (brute force attack). The system should also use a sufficiently large character set with which the password is formed. Instead of entering passwords manually, keys can also be stored in a key file. In applications such as SSH, in addition to authentication with a password, a public key procedure can also be used. The advantage is that the other party does not see the secret private key. Here, too, the private key is kept in a file and can be protected against unauthorized reading with a password.

The key file is an alternative to entering a password manually. This means that significantly longer and more complex keys can be used and there is no longer any risk of forgetting the password. However, the key file can be lost due to data loss. The attack scenario for a password consists of spying (e.g. through a keylogger) or guessing (e.g. through a dictionary attack); a key file, on the other hand, must be protected against unauthorized access so that it is not copied. Key files are therefore often encrypted with a master password.

The brute force method

The brute force method (from English brute force, brute force ') or method of raw violence, also exhaustion method (short exhaustion from Latin exhaurire, exhaust'), is a method of solving problems in the fields of computer science, cryptology and game theory, based on trying out all possible (or at least many possible) cases. The term exhaustive search is also used.

No efficient algorithms are known for many problems in computer science. The most natural and simplest approach to an algorithmic solution to a problem is to try out all the potential solutions until the right one is found. This method is called "brute force search".

The brute force search is easy to implement and designed to find the correct solution. However, the amount of computing operations increases in proportion to the number of possible solutions to be tried, and the number of these possible solutions often increases exponentially rapidly with increasing problems.

An important area of application is in computer security. A frequently used application example for the brute force method here is breaking or colloquially “cracking” passwords.

For the example of "password cracking", it can be concluded from the above-mentioned relationship between the scope of the problem and the number of required arithmetic operations that with increasing password length or increasing number of characters that may be present in the password (alphabet without numbers, with numbers, with special characters ) the effort of the brute force method increases quickly. The method is often successful in practice, since most users use short and simple, and therefore unsafe, passwords. With the right tools, millions of passwords per second can be tried out on standard mid-range computers.

In practice, brute force attacks are also made more difficult by the fact that the number of attempts is limited and access is blocked after a few unsuccessful password entries or further attempts are only possible after a waiting period. ^[2] Nevertheless, it was announced in September 2014 that, for. B. Apple had not implemented such simple measures in its iCloud for a long time and at least simple brute force attacks would be possible

SIM card

The SIM card (from the English subscriber identity module for "subscriber identity module") is a chip card that is inserted into a mobile phone and is used to identify the user in the network. It is used by mobile operators to provide mobile telephone and data connections to participants.

The SIM is a small processor with memory (usually in ID-000 format that is broken out of an ID-1 format card). It can be protected against unauthorized use by a changeable PIN. With the help of SIM, the mobile equipment (usually the mobile phone) is assigned to a network and authenticated. For this purpose, the IMSI is stored on the SIM, which is transmitted unencrypted when searching for a network and logging into a radio network and allows listening in on mobile phone calls and limiting the location of the mobile phone within a radio cell (IMSI catcher). Other sequences of numbers and algorithms stored on the SIM are used to encrypt the voice and signaling data (ciphering). The SIM is also used to store temporary, network-related data as well as preferred and blocked networks. In addition, a telephone and notebook, memory for short message service messages (SMS) and memory of the last called phone numbers can be integrated. SIM and mobile equipment together form the mobile station in GSM.

In 2012, around 115 million SIM cards were in circulation in Germany.

SIM card reader

The SIM card is often delivered in the large ID-1 format (85.6 mm x 54 mm). The smaller ID-000 part (25 mm x 15 mm) can be broken out. Due to the ever smaller mobile devices, the small ID-000 format was introduced over time for D-Netz devices. There are now a multitude of devices that use the even smaller micro SIM instead. The smallest format, the nano-SIM, is already used in many modern smartphones.

A SIM toolkit makes it possible to store small programs on a SIM card, for example info services, with which current information about politics, sport, weather can be delivered. Mobile operators O ₂ , E-Plus, T-Mobile and Vodafone use this to offer their home zone service. With the help of the SIM toolkit, it is shown whether the mobile phone is in the home zone. Functions such as topping up or checking the credit (with prepaid prepaid cards) are possible. The advantage of applications on the SIM card is that they can be used regardless of the device used (thus the cell phone can be changed without any apparent change in functionality).

Various manufacturers are currently working on the development of a SIM card with a larger storage space, similar to the well-known memory cards such as SD cards. This memory, previously up to 128 GB, can be used freely for MP3 audio or other documents.

A SIM Access Profile is a technique with which, for. B. in the car, the SIM data of a Bluetooth-equipped mobile device can be read from a permanently installed device and this itself establishes the radio connection. The data transmission can be improved by the permanently installed external antenna and the power consumption of the mobile phone can be reduced.

In dual SIM cell phones or with the help of dual SIM adapters, two or more SIM cards can be accommodated in one device, which are either active simultaneously (simultaneously) or alternatively (alternately).

There are eight contact areas on a SIM card. Different cards vary in number and division, but only these eight contacts with the following assignment were specified: V _cc - supply voltage C1 C5 GND - ground Reset - Reset for Sim CPU C2 C6 V _pp - programming voltage CLK clock C3 C7 I / O data reserved C4 C8 reserved

The operating voltage is supplied to the SIM card via Vcc and GND. There are SIM cards with an operating voltage of 1.8 volts, 3 volts and 5 volts for the older card generation (see table types). The voltage in question is printed on the SIM card in some cases. ^[4]

If a SIM card with the wrong voltage is used in a mobile phone, error messages, crashes or unusually fast battery discharge can occur.

If a SIM card no longer responds to requests from the mobile device, it can be restarted using the reset contact. The clock of the mobile device for synchronizing the data transfer taking place via the I / O contact is transmitted via CLK.

The optional programming voltage V _pp is only required during production in order to initialize or delete the internal software of the card. The normal reading and writing processes on the user area of a SIM card (e.g. in the context of use in a mobile device) manage without this voltage.

The two additional contact pins are reserved for currently still rare eight-pin SIM cards, as they will be used in future mobile devices - there are currently several competing designs for what these contacts should be used for. a. SIM cards with very high storage capacities are under discussion, which could be connected via a variant of the USB protocol. Other ideas concern special encryption functions or near field communication (NFC). However, current European mobile phones still use only six-pin SIM cards.

The I / O unit controls access to the SIM card. It is the interface of the CPU to the mobile device. The CPU is mainly used for memory management, but it can run small programs. The memory consists of a ROM, a RAM and an EEPROM. The operating system of the card is stored in the ROM. Brandings of the mobile phone companies are saved there (start logos). The RAM contains the data just used, it is volatile. User data are stored in the EEPROM.

lifespan

SIM cards have a limited lifespan. The memory used ages with each erase-write cycle of the non-volatile card memory, for example during authentication in the network. Originally, the manufacturers of the SIM chips guaranteed 100,000 such cycles. ^[5] In current chips, this value is 500,000 to one million. In order to defuse this process, the SIM manufacturers install protection mechanisms in the operating system. ^[6]

Irrespective of this, some older SIM cards are not recognized by current mobile phones. One reason may be that the SIM card no longer works with the voltage provided by the device. Another reason may be that the device requires a USIM card.

Formats

In the technical world, the hardware of the SIM card is called Universal Integrated Circuit Card or UICC for short.

Since the European Institute for Telecommunications Standards developed the UMTS standard at the end of the 1990s, it has been assumed that mobile devices will be smaller in the future or at least have less space inside and that SIM cards with a small size will therefore be required.

Full-size SIM

The first GSM devices had a slot to insert SIM cards in credit card format. Often these SIM cards were also inserted under the battery, e.g. B. the Sharp TQ-G700. Another example of such a device is the D-Netz mobile phone "Siemens S3com" from 1995. ^{[8] [9] [10]} The design of the devices was correspondingly at least as wide as a check card.

Since the SIM chip did not take up such a large area, the significantly smaller UICC format was already established at the end of the 1990s. That is why only a few devices with full-size SIM came onto the market. In the early days, the UICC SIM card was punched out of the credit card-sized SIM card; later the MINI SIM cards could be broken out of the full-size SIM card. In the opposite case (for a device with a credit card-sized SIM card) i. d. Usually the original card (from which the UICC SIM card was punched out or broken out) can be used as an adapter.

Mini SIM (UICC)

The mini SIM card (abbreviation 2FF for "second form factor") is only 25 mm x 15 mm in size and just as thick as the full-size SIM.

Some SIM cards are still delivered in credit card format, but the mini SIM is already pre-cut so that it only has to be broken out at predetermined breaking points. In the beginning, the mini-SIM was not pre-punched in the delivered full-size SIM, so there were instructions for self-assembly (cutting out with a template and scissors) in addition to punching devices. To save material, the SIM card has often only been supplied in UICC format in a cardboard template since the mid-2010s.

Micro SIM (Mini UICC)

The micro SIM (abbreviation 3FF for "third form factor") is 52% smaller than that of the mini SIM card. The outer lengths of the micro SIM are only 15 mm x 12 mm. As with the full-size SIM or mini-SIM, the thickness is 0.76 mm. There are no differences regarding the technical data of the circuit.

A micro-SIM can be made from a full-size SIM or mini-SIM using a special punching device. ^[11]

One of the first devices to use a micro SIM card was the iPad in 2010, followed by the Apple iPhone 4. Nokia uses this type of card, for example the Nokia N9 or the Nokia Lumia 800. Motorola uses the Motorola Droid Razr Micro SIM cards. Many other manufacturers have followed the trend and are now using micro SIM cards in their smartphones. ^[12]

Nano SIM

With 12.3 mm x 8.8 mm x 0.67 mm, the nano-SIM (short 4FF for "Fourth Form Factor") is another 40% smaller but above all 12% thinner than a micro-SIM and should therefore fit in save on compact devices. Cards in nano SIM format offer the same functionality as larger cards. The standard includes mechanical backward compatibility, which should allow a simplified distribution. ^[13]

Apple and Nokia initially wanted to have their version standardized as better. ^[11] The ETSI finally decided in June 2012 for the design proposal from Apple. This is compatible with the micro SIM cards already in use. ^[14] The nano-SIM card was launched on the market in September 2012 with the iPhone 5. Meanwhile, several modern smartphones offer a nano-SIM slot.

Although a punching, as described for the micro-SIM, is described as not possible for the nano-SIM, ^[11] warned against it or not mentioned at all, ^[15] there are numerous articles with instructions on the World Wide Web ^[16] , Cutting templates, ^[17] punching tools ^[18] and videos. ^[19]

Mobile phone providers warn against punching, and it is usually advisable to order a new SIM card for a fee. ^[20]

embeddedSIM

The embeddedSIM (eSIM) replaces the classic physical SIM card. First devices like Samsung's Smartwatch Gear S2 , Apple Watch Cellular (from Series 3rd ), new Apple iPhones ^[21] use this. ^[22] It is smaller than SIM cards, installed directly in the device and cannot be physically replaced. In the future, manufacturers will no longer need to take up the SIM card mechanism. The eSIM is electrically compatible with 2FF and 3FF cards, it uses the SON-8 format and is designed for M2M (machine to machine) applications. ^[23]

In Germany, the eSIM is supported and offered by the network operators Telekom ^[24] , Vodafone ^[25] and Telefönica Deutschland ^[26] .

NFC SIM

An NFC SIM is required to use the mobile payment functions. This has a second completely separate and encrypted area (Secure Element), to which only the bank has access. The card receives the data for the bank function so that it is retained when the device is changed. It is also possible to save several bank cards on one NFC SIM. ^{[27] [28]} Externally, the cards do not differ from those without NFC. The cards are also available in three sizes: mini, micro and nano.

Austria

The "Digital ATM card" payment system was tested in a field trial in Austria from June 2015 and has been offered by all major banks and the three major mobile operators since early 2016, but only for Android devices. The exchange of the SIM at the mobile network provider is necessary, so far new customers are not yet automatically equipped with NFC SIMs. The digital ATM card can then be ordered from the house bank. ^[29]

Byte does not indicate the number of characters that can be stored on the SIM, e.g. B. only one nibble is used for each digit of the number.

However, one must note that not all mobile phones use the possible number of characters (for the name and number).

The extended memory can be used freely by the operating system of the mobile phone, which means that the information stored there is not interpreted or misinterpreted by another mobile phone. So this memory area was z. B. from some devices (e.g. Siemens A60 ) used to extend the number of characters for the name for the first entries, on other devices this was used to store a second phone number.

Country specifics

On February 13, 2009, the German Federal Council approved a regulation of the Federal Ministry of Economics and Technology, according to which emergency calls ( 110 and 112 ) can no longer be dialed without a SIM card. ^{[36] [37]} Since emergency calls from cell phones without cards had been made more and more without reason, communication participants that could only be identified by SIM cards should now have this option.

safety

New SIM cards have better security features than older SIM cards. For security reasons, all SIM cards older than ten years should be replaced with new SIM cards.

DES encryption
→ Main article: “SIM cards DES-Hack” in the article Karsten Nohl

On the Black Hat 2013 or the OHM 2013 Karsten Nohl demonstrated that many mobile phones still use SIM cards with DES encryption, which has long been considered insecure. ^{[38] [39] [40]} In Germany, the IT industry association Bitkom and the major telecommunications providers Deutsche Telekom, Telefónica, E-Plus Group and Vodafone reacted calmly, as the insecure DES encryption is no longer used. ^[41]

Key theft

Based on published secret documents from whistleblower Edward Snowden, The Intercept reported in February 2015 that the National Security Agency and Government Communications Headquarters had stolen keys from Gemalto, the largest SIM card maker, in 2010. They are thus able to eavesdrop on a large part of the worldwide mobile communication including voice messages and data. ^[42] In one of the documents the German company Giesecke & Devrient is mentioned as the target. ^[43]

USIM application

The USIM application enables the mobile station to better encrypt calls, messages and data transmitted over the mobile network. The mobile station can better secure the authentication of the mobile station with the mobile radio provider thanks to the USIM application. For security reasons, SIM cards with the USIM application should be used in all mobile stations. Mobile stations that do not support the USIM application should be replaced by newer devices for security reasons.

Wireless Local Area Network (WiFi)

Wireless Local Area Network ['waӀәlIs laukl' εәɹIә 'nεtwз: k] (Wireless LAN or W-LAN, mostly WLAN; German wireless local network) denotes a local radio network, usually referring to a standard of the IEEE 802.11 family. In some countries (e.g. the USA, Great Britain, Canada, the Netherlands, Spain, France, Italy), the term Wi-Fi is used widely or synonymously for this narrower meaning. The term is also often used misleadingly as a synonym for WLAN hotspots or wireless Internet access. ^[1]

In contrast to the Wireless Personal Area Network (WPAN), WLANs have greater transmission powers and ranges and generally offer higher data transmission rates. WLANs make adjustments to the layer 1 and 2nd of the OSI reference model, whereas in WPANs e.g. B. a network connection is established via an emulation of the serial interface and PPP or SLIP provided in the network protocol. Today, the OFDM modulation method is mostly used for WLAN.

Operating modes

WLANs can be operated in different modes depending on the hardware configuration and the needs of the operator:

Infrastructure mode

• • Netzwerkname („Service Set Identifier“, SSID),
• • Liste unterstützter Übertragungsraten,
• • Art der Verschlüsselung.

The structure of the infrastructure mode is similar to that of the mobile network: A wireless access point, often in the form of a router, takes over the coordination of all clients and sends small data packets, so-called "beacons" (adjustable "beacons") at adjustable intervals (usually ten times a second). , cf. German "beacon"), to all stations in the reception area. The beacons include the following information:

• • Network name ("Service Set Identifier", SSID),
• • List of supported transfer rates,
• • Type of encryption.

This "beacon" makes connection establishment considerably easier, since the clients only need to know the network name and optionally some parameters for the encryption. At the same time, the constant sending of the beacon packets enables the reception quality to be monitored - even when no user data is being sent or received. Beacons are always sent at the lowest transmission rate (1 Mbit / s), so the successful reception of the "beacon" does not guarantee a stable connection to the network.

SSID transmission (broadcasting) can usually be deactivated, even if this violates the actual standard. This makes the wireless access point itself invisible. In this variant, however, the clients actively establish the connection by actively searching for all saved network names of "hidden" networks at any time if there is no connection. The problem here is that this information can easily be used for an attack on the end devices by the attacker simulating the presence of the access point. ^[2]

Since WLAN on the data link layer (layer 2nd uses the same addressing as Ethernet in the OSI model), a connection to wired networks (in WLAN jargon "Distribution System", DS) can easily be established via a wireless access point with an Ethernet connection. An Ethernet network card cannot distinguish whether it communicates with another Ethernet network card or (via an access point) with a WLAN card. However, you have to convert between 802.11 (WLAN) and 802.3 (Ethernet).

• • Die Frequenzbereiche der Basisstationen überlappen sich und führen zu Störungen.
• • Da - anders als bei Mobilfunknetzen - die gesamte „Intelligenz“ im Client steckt, gibt es kein echtes Handover zwischen verschiedenen Basisstationen. Ein Client wird im Normalfall erst nach einer neuen Basisstation suchen, wenn der Kontakt zur vorherigen bereits abgebrochen ist.

The standard provides for the construction of large WLANs with several base stations and uninterrupted change of clients between the different base stations. In practice, however, problems arise:

• • The frequency ranges of the base stations overlap and lead to interference.
• • Since - unlike with cellular networks - the entire "intelligence" is in the client, there is no real handover between different base stations. A client will normally only search for a new base station if the contact to the previous one has already been broken.

One solution to this problem is to relocate the control functions to the base stations or the network: a central authority can better control frequencies, transmission power, etc. B. also initiate a handover. Since the base stations lose part of their functionality in such a scenario and must be able to communicate directly with the central instance, work is being carried out on corresponding device classes (lightweight access point) and protocols. Proprietary solutions have been around for a few years, but open standards (e.g. the Lightweight Access Point Protocol) are still in the works. Discussions are sparked above all by the question of which device should perform which functions.

Ad hoc mode

In ad hoc mode, no station is particularly distinguished, but all are of equal value. Ad hoc networks can be set up quickly and with little effort, but other technologies, such as Bluetooth, are more common for the spontaneous networking of fewer end devices.

The requirements for ad hoc mode are the same as for infrastructure mode: All stations use the same network name ("Service Set Identifier", SSID) and optionally the same settings for encryption. Since there is no central instance (access point) in an ad hoc network, its coordinating function must be taken over by the end devices. A forwarding of data packets between the stations is not intended and in practice is not possible without further ado, because in ad hoc mode no information is exchanged that could give the individual stations an overview of the network. For these reasons, the ad hoc mode is only suitable for a very small number of stations, which must also be physically close to each other due to the limited range of the transmitters. If this is not the case, it can happen that one station cannot communicate with all other stations, because they simply no longer receive a signal.

To solve this problem, the participating stations can be equipped with routing capabilities so that they are able to forward data between devices that are not within range of each other. The collection and exchange of routing information is part of the upgrading of an ad hoc network to a mobile ad hoc network: software components on each station collect data (e.g. on the "visibility" of other stations, connection quality etc.) and exchange them among themselves and make decisions for the forwarding of user data. Research in this area has not yet been completed and, in addition to a long list of experimental protocols (AODV, OLSR, MIT RoofNet, BATMAN etc.) and standardization proposals (Hybrid Wireless Mesh Protocol, 802.11s), also has some commercial solutions (e.g. Adaptive Wireless Path Protocol from Cisco). See also in this context: Free radio network.

Wireless Distribution System (WDS) and repeating

There are various methods for increasing the range of existing radio networks or connecting wired networks via radio (wireless bridging) → see Wireless Distribution System.

Range and antennas

The permissible equivalent isotropic radiation power (EIRP) of 100 mW (2.4 GHz) or 500 mW (5 GHz) of standard 802.11 end devices suggests a range of 30 to 100 meters in open space. Some WLAN devices allow the connection of an external antenna. Directional antennas can be used to cover several kilometers in the open. In closed rooms, the range is heavily dependent on obstacles and the type and shape of the development.

Lightweight walls reduce the range due to damping and - depending on the (metal) support structure used and the type of bottom film - can be a major obstacle. Stone and concrete outer walls, in particular, dampen, especially due to moisture, as well as metal-vapor-coated glass panes or fire protection constructions. The higher the electrical conductivity of the material, the stronger the damping.

Surfaces can also act as reflectors and thus improve the range.

WLAN according to IEEE 802.11h (maximum 54 Mbit / s gross) works in the 5 GHz band, in which a larger frequency range (455 MHz bandwidth) is available and thus 19 non-overlapping frequencies (in Germany) can be used without a license. (See also, for the USA: U-NII) In normal operation, buildings according to IEEE 802.11h 200 mW equivalent isotropic radiation power (EIRP) are allowed. However, only a small part of the frequency range can be used without further requirements (TPC, Transmitter Power Control and DFS, Dynamic Frequency Selection). Only a small frequency range with TPC and DFS is allowed outdoors. This also allows higher equivalent isotropic radiation powers up to 1 watt EIRP. ^[32] TPC and DFS are designed to ensure that satellite links and radars are not disrupted. As primary licensees, they are privileged to use WLAN.

Special directional antennas can be used to cover several kilometers in the event of visual contact. In some cases, records are set up with connections of up to a hundred kilometers, in which no transmit amplifiers are used, but only antennas with high profits. However, this only works with a quasi-optical view and the first Fresnel zone is as free as possible. However, the permissible equivalent isotropic radiation power (EIRP) is usually significantly exceeded.

Antennas bring both a transmission and a reception gain (antenna gain, specified in dBi) by bundling electromagnetic waves. Therefore, instead of the transmission power, the so-called equivalent isotropic radiation power must be used as a limitation.

In Europe, the equivalent isotropic radiation power of WLAN systems at 2.4 GHz to 100 mW (= 20 dBm) is EIRP, at 5.15-5.35 GHz over 5.25 GHz with TPC and DFS to 200 mW (= 23 dBm) EIRP, or at 5.47-5.725 GHz with TPC and DFS limited to 1000 mW (= 30 dBm) EIRP.

For the EIRP see also: Equivalent isotropic radiation power, section Practical calculation.

safety

Without measures to increase information security, wireless local networks are exposed to attacks, such as snarfing or man-in-the-middle attacks. Therefore, an attempt is made to prevent this, or at least to make it significantly more difficult, using appropriate means, in particular by using encryption and passwords (authentication).

Encryption

Part of the WLAN standard IEEE 802.11 is Wired Equivalent Privacy (WEP), a security standard that contains the RC4 algorithm. The encryption contained therein with a static key that is only 40 bits (called 64 bits) or 104 bits (called 128 bits), for some manufacturers also 232 bits (called 256 bits) is not sufficient to secure the WLAN sufficiently. Known plaintext attacks are possible by collecting key pairs. There are freely available programs that can decrypt the password even without a complete package run, provided a fast computer is required. Every user of the network can also read all traffic. The combination of RC4 and CRC is considered cryptographically insecure.

For these reasons, technical additions have been developed, such as WEPplus, Wi-Fi Protected Access (WPA) in anticipation and subset to 802.11i, Fast Packet Keying, Extensible Authentication Protocol (EAP), Kerberos or High Security Solution, all more or less well reduce the security problem of WLAN.

The successor to WEP is the security standard 802.11i. It offers increased security through the Advanced Encryption Standard (AES) (with WPA2) and is currently not decryptable as long as none trivial passwords are used that can be cracked using a dictionary or even brute-force attack.

WPA2 is the equivalent of the Wi-Fi Alliance to 802.11i, which works with the encryption algorithm AES (Advanced Encryption Standard with key lengths of 256 bits) and is mostly supported in newer devices. Some devices can be retrofitted by replacing the firmware with WPA2 support. However, encryption is usually done without hardware acceleration, so that the gain in security is bought through a strong loss in transmission rate.

An alternative approach is to shift all encryption to the IP level. Data traffic is protected, for example, by using IPsec or a VPN tunnel. In free radio networks in particular, the incompatibilities of different hardware are avoided, central user administration is avoided and the open character of the network is preserved.

For the legal situation, see below.

In so-called "WarWalking" (or when driving through entire areas called Auto Wardriving), open WLANs are searched for with a WLAN-capable notebook or PDA. These can be marked with chalk (WarChalking). The aim is to uncover security gaps and report them to the operator and to investigate the spread of WLAN, or to use them for your own benefit (surfing free of charge and under a different name).

Authentication

Extensible Authentication Protocol is a protocol to authenticate clients. It can use RADIUS servers for user administration. EAP is mainly used within WPA for larger WLAN installations.

Authentication is also possible via the MAC address of the wireless network adapter. The MAC address is a hardware identifier that can be used to identify each connected network adapter. Most access points or routers offer the option of only allowing access for certain MAC addresses. No IP address is assigned to all MAC addresses that are not permitted, or access to the access point is blocked. However, a sole backup via MAC address filtering is not secure, since such addresses can be set without any problems. Valid MAC addresses can e.g. B. can be found by listening to the data traffic of other participants. But encryption can also be cracked in this way.

Basic security measures

• • Aktivierung der Verschlüsselung mit einer sicheren Verschlüsselungsmethode, d. h. mindestens WPA, besser WPA2; dabei spezifische Hinweise zur Sicherheit der gewählten Verschlüsselungsmethode im jeweiligen Artikel beachten
• • Vergabe eines sicheren Netzwerkschlüssels
• • Ersetzen der werkseitig voreingestellten Router- beziehungsweise Access-Point-Passwörter, da diese z. B. bei Arcadyan (einige Easybox- und Speedport-Modelle) anhand der BSSID errechnet werden können^[33][34]
• • Deaktivieren von Wi-Fi Protected Setup, wenn die Funktion nicht (mehr) benötigt wird^[35]
• • Änderung des werkseitig voreingestellten SSID-Namens, so dass keine Rückschlüsse auf verwendete Hardware, Einsatzzweck oder Einsatzort möglich sind (minimaler Sicherheitsgewinn, da anhand der BSSID meist auf die Hardware Rückschlüsse gezogen werden können)
• • Deaktivierung der Fernkonfiguration des Routers, soweit vorhanden (insbesondere bei privaten Haushalten)
• • Konfiguration des Access Point nach Möglichkeit nur über kabelgebundene Verbindungen vornehmen beziehungsweise Konfiguration per WLAN deaktivieren
• • Ausschalten von WLAN-Geräten, solange sie nicht genutzt werden (Zeitmanagement)
• • regelmäßige Firmware-Aktualisierungen des Access Point, um sicherheitsrelevante Verbesserungen zu erhalten
• • Trennung des Access Point vom restlichen (kabelgebundenen) Netzwerkteil mit Hilfe von VLANs und gleichzeitiger Einsatz einer Firewall zwischen den Netzwerkteilen

This includes some basic settings on the router or access point:

• • Enabling encryption with a secure encryption method, ie at least WPA, better WPA2; pay attention to specific information on the security of the selected encryption method in the respective article
• • Allocation of a secure network key
• • Replace the factory-set router or access point passwords, as these z. B. at Arcadyan (some Easybox and Speedport models) can be calculated using the BSSID ^{[33] [34]}
• • Deactivating Wi-Fi Protected Setup when the function is no longer required ^[35]
• • Change of the factory-set SSID name so that no conclusions can be drawn about the hardware, purpose or location used (minimal security gain, since the BSSID can usually be used to draw conclusions about the hardware)
• • Deactivating the remote configuration of the router, if available (especially for private households)
• • If possible, configure the access point only via wired connections or deactivate configuration via WLAN
• • Switch off WLAN devices as long as they are not being used (time management)
• • Regular firmware updates of the access point in order to receive security-relevant improvements
• • Separation of the access point from the rest of the (wired) network part using VLANs and simultaneous use of a firewall between the network parts

Social relevance

The widespread use of wireless networks in recent years underscores the trend towards more mobility and more flexible working conditions. As early as 2005, more notebooks were sold as desktop computers in the European Union, most of them with built-in WLAN chips. Public and commercial WLAN access points with internet connection, so-called "hot spots", enable access to the global data network in many places. The Wifi4EU initiative, for example, with which the EU subsidizes the provision of free WiFi networks in public institutions, shows their social importance.

In any case, private users will find DSL access devices with built-in access points almost everywhere, which telecommunications providers often offer at a discount along with the Internet connection.

More applications

WLAN can also be used as a platform for localization in cities and buildings. Since the beginning of 2008, the Fraunhofer Institute for Integrated Circuits has been operating a test environment on an area of 25 square kilometers in Nuremberg. ^[38] After an initial operating phase, the system is to be extended to other German and European cities such as Berlin, Munich, Frankfurt, London, Paris and Milan. ^[39]

Google and Apple use the data from WLANs to localize users. They thus offer an alternative to localization using GPS. ^[40]

Intensive research is being carried out into the extent to which WLAN can also be used in public road traffic in order to increase traffic safety. ^[41]

See also: WLAN-based location

Legal situation in Germany

The question of the extent to which the connection holder of a WLAN is liable for violations of third parties committed under the IP address of the connection holder was controversial. ^[42] In this context there is also the legal question of which protective measures a subscriber has to take at all and where, where appropriate, reasonable protective measures (so-called "inspection and monitoring obligations") end.

The Hanseatic Higher Regional Court ruled that a custodial parent is also liable as an interferer for copyright violations committed by his children. It was reasonable for the parents to take technical measures to prevent the use of illegal exchanges (decision of October 11, 2006 - 5 W 152/06). The Cologne Higher Regional Court also saw liability for copyright infringements not only as given for a GmbH as a joint owner, but also sentenced the managing director of the GmbH to personal liability from the point of view of liability for interference (decision of May 8, 2007 - 6 U 244/06 ).

The Higher Regional Court of Frankfurt am Main held the opposite view. The judges ruled that the holder of an Internet connection is generally not liable as an interferer for the unauthorized use of a WLAN connection by unauthorized third parties who are not connected to him. ^[43] In the opinion of the district court of Munich I, there is also no liability for a radio station for the violations of rights committed by a volunteer, since no company can comply with unlimited employee monitoring obligations (judgment of October 4, 2007 - 7 O 2827/07).

This inconsistent case law meant that such a case was pending before the Federal Court of Justice. The 1st Civil Senate, which is responsible for copyright, announced on May 12, 2010 a fundamental decision on liability issues. Accordingly, private individuals cannot, on injunctive relief on the other hand, claims for damages are made if your insufficiently secured WLAN connection is used by unauthorized third parties for copyright infringements on the Internet. ^[44] A decision on what the legal situation is for WLANs, which the provider deliberately directs to the public, is still pending.

In addition, the question arises whether anyone who uses an open, foreign WLAN without authorization is punishable by law. This unauthorized use is sometimes referred to as "black surfing" in reference to "illegal driving". The district court of Wuppertal decided in 2007 that a “black surfer” would be punishable for a violation of §§ 89, S. 1, 148 I 1 TKG and §§ 44, 43 II No. 3 BDSG. ^[45] After a decision by the same district court in 2010, "black surfing" should no longer be punishable. ^[46] The district court Wuppertal upheld that decision. Black surfing is not punishable under any legal aspect. ^[47]

With the amendment to the Telemedia Act enacted on July 21, 2016, an amendment to Section 8 (3) made it clear that access providers who provide users with Internet access via a wireless local network are also privileged. This regulates that WLAN operators fall under the so-called provider privilege. However, the actual abolition of interference liability did not initially make it into the legal text. Instead, the justification of the law only contained a note that the legislature would like to see that WLAN operators can no longer be warned of third-party violations and can be claimed for omission.

Real legal security for open radio networks has just not yet been achieved. In contrast to the actual legal text, the reasoning is not binding. Courts can use them for interpretation, but do not necessarily have to share the view presented there. Therefore, the TMG amendment of 2016 did not yet achieve a breakthrough in the adjustment of interference liability. To do this, the legislator should have specifically exempted operators from the law, in particular from injunctive relief.

This only came about through a further change in the law in mid-2017. According to this, the new version of Section 7 (4) sentence 3 TMG clarifies that the access providers are no longer liable for the behavior of WLAN users. Despite this renewal of the legal situation, there are still a number of legal requirements for the operation of public WLAN networks, such as data protection. ^[50]

For the current legal situation, see liability for interference.

Discussion of health effects

The radio frequencies used by WLAN devices are around 2.4 GHz and 5.4 GHz, i.e. in the microwave range. WLAN is therefore discussed in connection with possible health effects in the context of electromagnetic environmental compatibility.

After several studies, u. a. of the Federal Office for Radiation Protection (BfS), there are no indications within the legal exposure limit values according to the current state of science that these high-frequency electromagnetic fields pose health risks.

The only guaranteed biological impact is thermal heating. ^[51] The associated process is called dielectric heating. In order to avoid damage caused by thermal heating, a limit value for the specific absorption rate was defined. In normal operation, this limit is far below in the case of remote operation. ^[52] Only laptop users come close to the limit values when they have their device on their thighs.

Regardless of previous knowledge, the Federal Office for Radiation Protection (BfS) generally recommends minimizing personal radiation exposure in order to keep possible, but as yet unknown, health risks low. ^[53]

There are isolated reports of people complaining about various complaints and tracing them back to WLANs themselves. Various examinations with electrosensitive people could not establish a connection between the complaints and electromagnetic radiation.

Wi-fi

fa ]) bezeichnet sowohl ein Firmenkonsortium, das Geräte mit Funkschnittstellen zertifiziert, als auch den zugehörigen Markenbegriff.Wi-Fi (English [wa

fa]) denotes a company consortium that certifies devices with radio interfaces, as well as the associated brand name.

Wi-Fi is an art term invented for marketing purposes, which was created in analogy to Hi-Fi. Whether it is an abbreviation like this is doubted; the Wi stands for wireless. ^{[1] [2]}

Wi-Fi is often used as a synonym for WLAN. Strictly speaking, however, WLAN and Wi-Fi are not the same: WLAN refers to the radio network, whereas Wi-Fi is certification by the WiFi Alliance based on the IEEE 802.11 standard - all Wi-Fi-certified products are therefore 802.11 compliant.

Wi-Fi Alliance

In 1999 the organization was originally founded under the name Wireless Ethernet Compatibility Alliance (WECA). In 2002, WECA changed its name to the Wi-Fi Alliance. ^[3]

The task of the Wi-Fi Alliance is to certify the products of different manufacturers on the basis of the IEEE 802.11 standard and thus to ensure operation with various wireless devices (interoperability). The background was that in many products the standard was not fully implemented or softened by proprietary extensions. This often resulted in incompatibilities between products from different manufacturers.

The Wi-Fi Alliance tests corresponding components according to its own guidelines. Products that pass the test receive the Wi-Fi certificate and can therefore bear the “Wi-Fi” logo. However, only the products of the Wi-Fi members are tested. In addition to the membership fee, members must pay a fee for each component tested. A missing Wi-Fi logo does not necessarily represent a deviation from the standard.

On October 31, 2002, the consortium announced that it would use Wi-Fi Protected Access (WPA) to establish a subset of the then future IEEE standard 802.11i as a new encryption technology in order to replace the WEP encryption method, which was considered unsafe before the new standard was adopted . After the adoption of 802.11i, Wi-Fi coined the term WPA2.

The Wi-Fi Alliance includes over 300 companies as members. Here is a selection of the members.

Bluetooth

.Bluetooth ['blu: tu: θ] is an industry standard developed by the Bluetooth Special Interest Group (SIG) in the 1990s in accordance with IEEE 802.15.1 for data transmission between devices over short distances using radio technology (WPAN). Connection-free and connection-based transfers from point to point and ad hoc or piconets are possible. The name "Bluetooth" is derived from the Danish King Harald Blauzahn (English Harald Bluetooth), who united enemy parts of Norway and Denmark. ^[1] The logo is a monogram of the Norse runes and *

.

The radio methods for Bluetooth were originally developed in large parts by the Dutch Professor Jaap Haartsen and the Swede Sven Mattisson for Ericsson. Other parts were mainly supplemented by Nokia and Intel. Bluetooth forms an interface through which small mobile devices such as cell phones and PDAs as well as computers and peripheral devices can communicate with each other. The main purpose of Bluetooth is to replace cable connections between devices.

Technical background

Devices according to the Bluetooth SIG standards transmit as Short Range Devices (SRD) in a license-free ISM band (Industrial, Scientific and Medical Band) between 2.402 GHz and 2.480 GHz. They can be operated worldwide without a license. However, interference can be caused, for example, by WLANs, cordless phones (DECT phones in Europe have a different frequency band) or microwave ovens that work in the same frequency band. To achieve robustness against interference, a frequency hopping method is used, in which the frequency band is divided into 79 channels at 1 MHz intervals, which are changed up to 1600 times a second. However, there is also Packet types in which the frequency is not changed as often (multislot packets). At the lower and upper end there is a frequency band as a security band ("guard band") to neighboring frequency ranges. Theoretically, a data transfer rate of 706.25 kbit / s when receiving and simultaneous 57.6 kbit / s when sending can be achieved (asymmetrical data transfer).

From version 2.0 + EDR, data with EDR (Enhanced Data Rate) can be transmitted a maximum of about three times as fast, i.e. at around 2.1 Mbit / s. From version 1.1, a Bluetooth device can maintain up to seven connections at the same time, whereby the devices involved must share the available bandwidth (shared medium).

Bluetooth supports the transmission of voice and data. However, most devices can only manage three participants in one piconet during the necessarily synchronous transmission of voice.

It is also possible to encrypt the transmitted data.

Classes and reach

class Maximum power Range ^[2] (mW) (dBm), general outdoors class 1 100 +20 approx. 100 m approx. 100 m 2nd grade 2.5 +4 approx. 10 m approx. 50 m Class 3 1 0 approx. 1 m about 10m

In addition to the transmission power, the range that can actually be achieved depends on a large number of parameters. These include, for example, the sensitivity of a receiver and the types of transmit and receive antennas used on radio communication links. The properties of the environment can also influence the range, for example walls as obstacles within the radio communication links. The types of data packets can also influence the achievable range due to differences in length and security mechanisms.

To enable higher transmission rates over the 2.45 GHz ISM frequency band available worldwide, the Bluetooth SIG is planning the Alternate MAC / PHY Bluetooth extension; Bluetooth is expanded to include the PHY and MAC layers of the IEEE 802.11 specifications (WLAN standards).

Eavesdropping and intrusion security

Bluetooth transmissions are only bug-proof or secure against unauthorized intrusion if they are operated as a connection with multi-stage dynamic key allocation. Security is restricted when static keys are assigned. When the key is transferred, this part of the communication is particularly at risk, since only the successful key exchange protects a connection.

Bluetooth is only considered safe if the PIN code is too short (about four decimal digits or less). In their spring 2005 article ^{[3], the} Israeli researchers A. Wool and Y. Shaked described a method by which eavesdroppers can interrupt an existing, tap-proof connection and possibly break into a new connection. This data phishing is based on interrupting an existing connection with appropriate interference signals and persuading the participants to re-establish an authenticated connection. The attacked must enter their PIN again in the devices used. The authentication that then takes place with renegotiation of the connection key can then be listened to using easily available special hardware and cracked if the PIN is poorly chosen (for example, because it has an eight-digit number) by trying it out. This brute force attack can be further accelerated by FPGA boards. This is not a purely academic attack, and there is a free program called BTCrack to prove it. ^[4] After a successful attack, the attacker is in possession of the secret connection key and can establish any connection to the attacked devices. However, the attacker must know the Bluetooth address of a connected Bluetooth module. Contrary to popular opinion, this cannot be prevented by the "invisibility mode". ^{[5] [6]}

This attack is possible if the attacker eavesdrops on the communication during the pairing process, the attacker carries out a re-authentication and the PIN is too short. There is therefore no danger for devices that permanently store the keys, since after connection failures or manual re-establishment of a connection, no new PIN authentication is triggered, but instead the keys stored on both devices are used. To protect against such attacks, the authors therefore recommend that remote sites are rarely registered with a PIN. It is safer to permanently save remote stations once they have been recognized in the respective authentication lists and to deactivate re-authentication using a PIN. In addition, users should use PINs longer than eight characters if the software used allows it. The Bluetooth protocol provides up to 16 arbitrary characters (128 bit). In addition, an unexpected prompt to re-authenticate should be heard and cautioned.

Error handling

1. 1. 1/3- und 2/3-FEC-Blockcodierung; ermöglicht Fehlerkorrektur beim Empfänger
2. 2. ARQ (Automatic Repeat Request), ermöglicht Fehlererkennung beim Empfänger. Bei Fehlern wird das entsprechende Paket neu angefordert.

Up to version 2.0, Bluetooth knows two elementary types of error handling (if used):

1. 1. 1/3 and 2/3 FEC block coding; enables error correction at the receiver
2. 2. ARQ (Automatic Repeat Request), enables error detection at the receiver. In the event of errors, the corresponding package is requested again.

System architecture

Scatternet (master = red, slave = green, parked = blue)

A Bluetooth network (Piconet) consists of up to eight active nodes, which can be addressed via a 3-bit address. All inactive devices can keep the synchronization in park mode and can be activated in the network on request. There is an 8-bit address for the parking mode, which can address 255 participants ("slaves"). In addition, the number of passive nodes can be increased again via the 48-bit device address. The "master" controls the communication and assigns transmit time units ("slots") to the "slaves" (time division multiplexing). A Bluetooth device can be registered in several piconets, but only act as a master in one network. Up to ten piconets form a scatternet (from to scatter), whereby the participants can contact each other. Each piconet is identified by a different frequency hopping sequence. However, the data rate usually suffers considerably in this Scatternet ^[7] .

Such self-organizing radio networks - Scatternet - are implemented in a proprietary manner, to date no general solution has been standardized. This is due to the fact that no algorithm can be defined that meets all the requirements of a Scatternet at the same time and is sufficiently lean and therefore fast. ^[8th]

Bluetooth baseband

Two different physical data channels are made available. The synchronous data transmission is intended for the transmission of voice data with a data rate of 64 kbit / s. This procedure is called circuit-switched or synchronous connection (Synchronous Connection-Oriented - SCO). The other form of transmission is packet switching or asynchronous connectionless (ACL), which requires a storage behavior of the transmission device, as in Internet technology. Everything except speech is transmitted via ACL, in addition to all types of data, especially music. The Bluetooth protocol supports an asymmetrical data channel with data rates in version 1.2 of a maximum of 732.2 kbit / s in one direction and 57.6 kbit / s in the opposite direction, or a symmetrical data connection with 433.9 kbit / s in both directions . In the EDR version, higher data rates can be achieved.

Up to version 1.2 there are only HV1, HV2 and HV3 packets with good error correction (HV1) up to none (HV3) for SCO transmission. These packets contain audio data for 1.25 ms, 2.1.25 ms or 3 * 1.25 ms and are accordingly sent every 1.25 ms, 2 * 1.25 ms and 3 * 1.25 ms. HV1 can be used when no other data needs to be sent. However, this operating mode has the highest power consumption, which is why almost all devices use HV3 packages. This has the advantage that you only need a third of the bandwidth for audio and the rest of the bandwidth can be made available for ACL connections to the same or to other devices.

With version 1.2, an extended synchronous transmission mode (enhanced SCO, eSCO) was introduced. To this end, new packet types and a more flexible division of the transmission period were introduced. This also makes it possible to transmit other audio formats such as. B. the SBC codec, which is also to be introduced in HFP version 2.1.

If no synchronous data packets are currently being sent, Bluetooth can offer asynchronous transmission. All services, both the sending of user data packets and the transmission of control information, are processed between two Bluetooth stations.

Bluetooth data packets consist of a 72-bit access code, a 54-bit header and a variable user data field from 0 bit to 2745 bit (packet type DH5). For Bluetooth 2.0 ° + EDR, up to 8168 bit user data per package (3-DH5) are possible.

Establishing a connection

A connection is always established under the protocol architecture according to Bluetooth V2.1 etc. (New is possible as of standard Bluetooth V3.0 and with the protocol Bluetooth V4.0 Low Energy, connectionless operation in the send and receive direction). ^[9] A connection can originate from any device, which rises to the "master" over the answering "slaves".

As soon as Bluetooth devices are put into operation, the individual Bluetooth controllers identify themselves within two seconds using an individual and distinctive 48-bit MAC address. In standby mode, unconnected devices listen for messages at intervals of up to 2.56 seconds (scan mode) and control 32 hop frequencies. The contact to the slaves is established by an inquiry message and then by a page message (from to page = = via loudspeaker), message =. if the hardware address of the devices is unknown. If the address is known, the first step is omitted. In the page state, the master sends 16 identical page telegrams on 16 different hopping frequencies, which are intended for the slaves. The stations are then connected in the status. On average, a connection is established within half the scan interval, e.g. B. 2.56 / 2 seconds (1.28 seconds).

If the master does not find a slave within a set time, page telegrams are sent on another 16 hopping frequencies. This grouping is intended to ensure a speedy connection when the slave clock is known. With adaptive hopping, the frequencies that are already occupied by other masters are omitted.

Since 2005, NFC can optionally be used to establish a connection between two Bluetooth devices. This additional RF protocol supports Bluetooth especially when pairing Bluetooth-OBEX for the first time.

Bluetooth protocol architecture

The Bluetooth specification was developed by the Bluetooth Special Interest Group (SIG). This contains protocols in a hierarchical order (protocol stack), with which interactive services and applications are possible that communicate via mobile radio connections. These are produced with the help of radio modules and are connectionless or connection-oriented.

The Bluetooth Special Interest Group (SIG) has also designed various application models for Bluetooth technology. The specification includes a description of the protocols with which these deployment models can be implemented. Special combinations according to these models are used with the profiles.

Bluetooth Low Energy is not an energy-saving mode, but a special protocol stack that differs from the previously known protocol stack, does not replace it, but opens up new possibilities for low energy consumption.

Energy saving modes

If no data is to be transmitted, a connection between a master and a slave can be put into an energy-saving mode.

• • Der HOLD-Modus wird zur asynchronen Abwesenheit eingesetzt. Zum Beispiel kann ein Slave mitteilen, dass er ab einem gewissen Zeitpunkt für 200 ms nicht zuhört. Der Master adressiert dann den Slave für die angegebene Zeit nicht, und der Slave hört dann auch nicht auf Master-Pakete. Beide Geräte können dann die Zeit für andere Aktivitäten nutzen (scanning, scatternet etc.).
• • Der SNIFF-Modus (von to sniff (engl.) = schnüffeln) wird zur reduzierten periodischen Aktivität eingesetzt. Es kann z. B. ein Slave oder Master mitteilen, dass er nur noch alle 500 ms für einige Zeitfenster („slots“) zuhört. Der SNIFF-Modus wird bei fast allen Geräten, die Energieverbrauch senken sollen, eingesetzt.
• • Der PARK-Modus wird eingesetzt, um ein Gerät synchronisiert zu halten. Das Gerät kann aber nicht aktiv am Datenverkehr teilnehmen. Der Park-Modus wird zwar von fast allen Chipsätzen unterstützt, aber trotzdem kaum angewendet.

There are three energy saving modes:

• • The HOLD mode is used for asynchronous absence. For example, a slave can announce that after a certain point in time it will not listen for 200 ms. The master then does not address the slave for the specified time, and the slave then does not listen to master packets. Both devices can then use the time for other activities (scanning, scatternet etc.).
• • The SNIFF mode (from to sniff) is used for reduced periodic activity. It can e.g. For example, tell a slave or master that it only listens every 500 ms for some time slots. The SNIFF mode is used for almost all devices that are intended to reduce energy consumption.
• • PARK mode is used to keep a device synchronized. However, the device cannot actively participate in data traffic. Park mode is supported by almost all chipsets, but is hardly ever used.

Details on reducing energy consumption in order to reduce the load on small batteries depend on the respective coordination of master and slave in all previous and new modes.

Security modes

• • Modus 1 (Non-Secure Mode): In diesem Modus gibt es keine Sicherheitsmechanismen. Die Geräte wechseln nur fortlaufend die Frequenz, um das Abhören zu erschweren.
• • Modus 2 (Service-Level Enforced Security): In diesem Modus liegt es bei den benutzten Diensten, auf dem Application Layer Sicherheitsmechanismen durchzusetzen. Dienste können für alle Geräte offen sein, nur eine Authentifizierung vorsehen oder noch zusätzlich eine Autorisierung erfordern.^[10]
• • Modus 3 (Link-Level Enforced Security): In diesem Modus findet schon beim Verbindungsaufbau eine Authentifizierung auf dem Link Layer statt. Verschlüsselung ist optional.^[11]

The Bluetooth standard defines the following three security levels, from the least secure to the most secure:

• • Mode 1 (Non-Secure Mode): There are no security mechanisms in this mode. The devices only change the frequency continuously to make listening difficult.
• • Mode 2 (Service-Level Enforced Security): In this mode it is up to the services used to enforce security mechanisms on the application layer. Services can be open to all devices, only provide authentication or additionally require authorization. ^[10]
• • Mode 3 (Link-Level Enforced Security): In this mode, authentication takes place on the link layer when the connection is established. Encryption is optional. ^[11]

Many mobile phones can transmit data via Bluetooth. Malicious attackers can cause high financial damage via Bluetooth through carelessly configured devices or incorrect implementations of the Bluetooth protocol in the devices by calling paid telephone and SMS services, read private user data, write phone book entries and manipulate the list of called numbers for cover-up . General, device-independent DoS attacks at the network protocol level are possible with simple means (eg "ping" requests with large packets). ^[12]

Bluetooth protocol stack

Bluetooth protocol stacks are software packages with drivers that enable connection to Bluetooth devices and contain services for using different Bluetooth profiles. Which stack you can use depends on the driver and the chip installed.

• • Affix
• • BlueFRITZ! von AVM (Entwicklung eingestellt)
• • BlueSoleil von IVT
• • BlueZ (Standard unter Linux)
• • In The Hand
• • IwBT
• • Microsoft
• • Stollmann
• • Toshiba^[13]
• • Widcomm von Broadcom

The best known protocol stacks and their manufacturers are:

• • Affix
• • BlueFRITZ! by AVM (development discontinued)
• • BlueSoleil from IVT
• • BlueZ (standard under Linux)
• • In The Hand
• • IwBT
• • Microsoft
• • Stollmann
• • Toshiba ^[13]
• • Broadcom Widcomm

• • Avetana
• • BlueCove

Bluetooth stack is also a term for software packages that are required for the development of Java applications with Bluetooth functionality. For example, if a J2ME application should be able to communicate with a J2SE server, a Bluetooth stack (see above) and a Bluetooth stack are required as an interface between the driver (e.g. Widcomm) and Java. Examples of Bluetooth stacks for Java are:

• • Avetana
• • BlueCove

Bluetooth profiles
→ Main article: Bluetooth profiles

Data is exchanged between Bluetooth devices according to so-called profiles, which are defined as a layer above the protocol layer for the control of certain services. As soon as a Bluetooth connection is established, the devices select the respective profile used and thus determine which services they have to provide for the respective other partners and which data or commands they require. For example, a headset requests an audio channel from a Bluetooth-compatible mobile phone and controls the volume setting or control via additional data channels.

history

Since the late 1980s, there have been various efforts to avoid the tangle of cables surrounding a computer installation using radio peripherals (e.g. radio keyboards, printers with an infrared interface, etc.). Various shortcomings (high power consumption, mutual interference, etc.) and above all the lack of standards prevented these beginnings from breaking through.

At that time, infrared technology was very popular in addition to radio technology, and it looked as if the latter would prevail. In August 1993, around 30 companies (including HP, IBM, Digital) merged to develop a cross-vendor protocol and founded the Infrared Data Association (IrDA). The aim was to create a uniform protocol for data transmission via infrared. Numerous insights from the IrDA development later flowed into the newly acquired Bluetooth radio standard.

However, the IrDA technology had to struggle with a central disadvantage: the necessary visual contact between the transmitter and the receiver. Therefore, in 1994 the company Ericsson was commissioned to carry out a feasibility study to find a radio-based replacement for cable connections. The study produced a positive result, and in 1998 Ericsson, Nokia, IBM, Toshiba and Intel founded the Bluetooth Special Interest Group (SIG) to develop a standard that laid down binding specifications. As the first final specification, SIG released version 1.0a in July 1999, version 1.0b followed in December of the same year. Only in February 2001, version 1.1 of the standard was presented. This was considered to be the first solid basis for marketable products because the previous versions had a number of inaccuracies and errors.

The name "Bluetooth" pays homage to the Danish Viking king Harald Blauzahn, who was known for his communication skills. He succeeded in largely unifying and Christianizing Denmark in the 10th century. ^[14] The name "Bluetooth" was originally a code name for the developed technology, which was later due to lack of good alternatives used as a brand name. The Scandinavian namesake was chosen because of the high level of participation by Ericsson and Nokia in Bluetooth development.

Older Bluetooth versions

• • Bluetooth 1.0 und 1.0B (Juli 1999) Enthielt Sicherheitsprobleme durch Bluetooth Hardware Device Address Transmission (BD_ADDR); maximale Datenübertragungsrate von 732,2 kbit/s
• • Bluetooth 1.1 (Februar 2001) Indikator für die Signalstärke hinzugefügt Received Signal Strength Indication (RSSI); maximale Datenübertragungsrate von 732,2 kbit/s
• • Bluetooth 1.2 (November 2003) Weniger empfindlich gegen statische Störer (zum Beispiel WLAN) durch Adaptive Frequency-Hopping spread spectrum (AFH); neue Pakettypen für synchrone Übertragung (eSCO); maximale Datenübertragungsrate von 1 Mbit/s
• • Bluetooth 2.0 + EDR (November 2004) Etwa dreifache Datenübertragungsgeschwindigkeit durch Enhanced Data Rate (EDR) mit maximal 2,1 Mbit/s; abwärtskompatibel, d. h., es können gleichzeitig EDR- und Nicht-EDR-Verbindungen bedient werden.
• • Bluetooth 2.1 + EDR (auch Lisbon Release genannt, August 2007) Neue Funktionen wie Secure Simple Pairing, Quality of Service.
• • Bluetooth 3.0 + HS (auch Seattle Release genannt, April 2009) Für diese Version ist die Unterstützung eines zusätzlichen Highspeed (HS)-Kanals auf Basis von WLAN und UWB verfügbar. Die Nutzung von WLAN ist dabei lokal deutlich eingeschränkt. Die Kommunikation funktioniert zwischen einzelnen Geräten (Peer-to-Peer) und nicht durch Verteilung (Multicast). Dafür braucht sich der Nutzer auch nicht anzumelden, die L2CAP-Protokollschicht wurde erweitert, um neben dem Standard-Bluetooth-Kanal zusätzlich diesen Highspeed-Kanal zu unterstützen. Damit kann eine theoretische Übertragungsrate von 24 Mbit/s erreicht werden. Bei UWB (Ultrabreitband) als physikalische Übertragungsart (basierend auf der Spezifikation ECMA-368) und WiMedia MAC als Protokollschicht waren bis zu 480 Mbit/s geplant. Auf dieser Spezifikation hätten auch andere Protokolle wie WUSB und IP aufgesetzt werden sollen. Die Spezifikation wurde im Oktober 2009 aufgegeben.^[15]
• • Bluetooth 3.0 + EDR „EDR“ steht für „Enhanced Data rate“.^[16]

A selection of important properties of the previous Bluetooth versions, all of which no longer correspond to the last revision of version 4.0 from December 2009 (see above) are:

• • Bluetooth 1.0 and 1.0B (July 1999) Contained security problems due to Bluetooth Hardware Device Address Transmission (BD_ADDR); maximum data transfer rate of 732.2 kbit / s
• • Bluetooth 1.1 (February 2001) signal strength indicator added Received Signal Strength Indication (RSSI); maximum data transfer rate of 732.2 kbit / s
• • Bluetooth 1.2 (November 2003) Less sensitive to static interferers (for example WLAN) due to Adaptive Frequency-Hopping spread spectrum (AFH); new packet types for synchronous transmission (eSCO); maximum data transfer rate of 1 Mbit / s
• • Bluetooth 2.0 + EDR (November 2004) Approximately three times the data transfer speed thanks to Enhanced Data Rate (EDR) with a maximum of 2.1 Mbit / s; downward compatible, ie EDR and non-EDR connections can be operated simultaneously.
• • Bluetooth 2.1 + EDR (also called Lisbon Release, August 2007) New functions such as Secure Simple Pairing, Quality of Service.
• • Bluetooth 3.0 + HS (also called Seattle Release, April 2009) Support for an additional high-speed (HS) channel based on WLAN and UWB is available for this version. The use of WLAN is significantly restricted locally. Communication works between individual devices (peer-to-peer) and not through distribution (multicast). The user does not need to register for this, the L2CAP protocol layer has been expanded to support this high-speed channel in addition to the standard Bluetooth channel. This enables a theoretical transmission rate of 24 Mbit / s to be achieved. Up to 480 Mbit / s were planned for UWB (ultra broadband) as the physical transmission type (based on the ECMA-368 specification) and WiMedia MAC as the protocol layer. Other protocols such as WUSB and IP should have been based on this specification. The specification was abandoned in October 2009. ^[15]
• • Bluetooth 3.0 + EDR "EDR" stands for "Enhanced Data Rate". ^[16]

Bluetooth 4.0

• • Der Standard 4.0 ist abwärtskompatibel mit allen Vorgänger-Versionen.^[21] Für Verbindungen mit den bisherigen Protokollen kommt eine verbesserte Fehlerkorrektur zum Einsatz, für das erforderliche Maß an Sicherheit soll eine AES-Verschlüsselung mit 128 Bit verwendet werden.
• • Bluetooth Low Energy/Smart ist ein Teil des 4.0-Standards, bietet allerdings keine Abwärtskompatibilität. Dafür ist es möglich, in weniger als fünf Millisekunden eine Übertragung aufzubauen und diese bis zu einer Entfernung von 100 Metern aufrechtzuerhalten.
• • Der wichtigste Vorteil bei Einsatz von Bluetooth Low Energy in neuen Endgeräten ist die Reduzierung des Stromverbrauchs durch Optimierungen, wie die kürzere Aufbauzeit für eine Übertragung oder die Schlafphasen zwischen den synchronisierten Sendezyklen. Allerdings können dadurch keine Audiodaten mehr übertragen werden.
• • Hybride Geräte, die sowohl Bluetooth Classic als auch Bluetooth Low Energy unterstützen, werden „Smart Ready“ genannt.

Specification 4.0 was adopted on December 17, 2009. This standard made the Low Energy protocol stack available for the first time ^[17] and new Low Energy profiles have been added continuously since then. Corresponding chips were available in small numbers from the fourth quarter of 2010, further indications suggest that cell phones equipped with Bluetooth 4.0 can be expected from the first quarter of 2011. Finally, in June 2011, Bluetooth 4.0-compliant chips were already available from Atheros, CSR, Nordic Semiconductor, ^[18] Texas Instruments, Toshiba and EM Microelectronic Marin ^{[19] [20]} .

• • The standard 4.0 is downward compatible with all previous versions. ^[21] Improved error correction is used for connections with the previous protocols, AES encryption with 128 bits is to be used for the required level of security.
• • Bluetooth Low Energy / Smart is part of the 4.0 standard, but does not offer backward compatibility. It is possible to establish a transmission in less than five milliseconds and to maintain it up to a distance of 100 meters.
• • The most important advantage when using Bluetooth Low Energy in new end devices is the reduction of power consumption through optimizations, such as the shorter setup time for a transmission or the sleep phases between the synchronized transmission cycles. However, audio data can no longer be transmitted as a result.
• • Hybrid devices that support both Bluetooth Classic and Bluetooth Low Energy are called "Smart Ready".

Announcements regarding the availability of devices with Bluetooth 4.0 remained speculative until mid-2011 and without confirmation of availability. ^{[22] [23]} Since then, a variety of different end devices from different manufacturers have been on the market that support the Bluetooth 4.0 standard. Since Android 4.0 only supported Bluetooth 4.0 in the middle of 2013, it came to the situation that some mobile phones supported Bluetooth 4.0 on the hardware side, but could not use this due to the lack of a corresponding Bluetooth protocol stack. ^[24]

Bluetooth 4.1

Version 4.1 of the Bluetooth specification was released in December 2013. ^[25] Direct thereon were announced the first devices with the new standard, eg. B. the Samsung Galaxy Note 4 ^[26] and the Nexus 6. ^[27]

Bluetooth 4.2 smart

The Bluetooth 4.2 standard was introduced in December 2014. The main focus during the development was extended security features, a higher transmission speed and an even more economical Bluetooth “Low Energy” mode. ^[28] Newer devices such as the Samsung Galaxy Note 5 ^[29] and the Apple iPhone 6 ^{[30] also} support this standard.

Bluetooth 5

On June 16, 2016, Bluetooth 5 was officially announced. According to this announcement, the range should be quadrupled (100 m) and the data rate doubled (2 Mbit / s gross without EDR). In addition, new services such as location transfer are to be introduced. ^[31] The final adoption took place on 6 December 2016th

Areas of application

computer

Special hardware is required to operate Bluetooth on the PC. Some computers (mostly notebooks) have these already integrated, otherwise small devices or PCMCIA cards connected to the USB interface are also available for this purpose. The operating system used also plays a crucial role. Under Microsoft Windows, it is no longer necessary to install a special driver since Windows XP SP2 thanks to the included Microsoft Bluetooth stack. However, a larger selection of supporting profiles is available with the Bluetooth stacks from other manufacturers. Current Linux distributions and Apple Macintosh models also support Bluetooth through their own certified Bluetooth stacks. If you have a PC with Bluetooth available, you can also use the appropriate software to find other Bluetooth devices within range and, depending on the software's functional scope, view a detailed list of the open services. Such software is called a Bluetooth scanner.

Bluetooth applications on the computer

• • SCO audio: synchronous headset operation (Skype, SIP, etc.)
• • AV or A2DP audio: HiFi music playback suitable for connecting one or more headphones
• • Mobile phone synchronization (contacts, music files, mobile internet access, etc.)
• • HID: input devices such as mouse and keyboard
• • Motion capturing: transmission of motion data to the evaluation computer (for example Xsens MVN)
• • Two-factor authentication according to the U2F standard of the FIDO alliance

Handsfree kits and headsets

Many car radios act as hands-free systems by integrating the mobile phone via Bluetooth, so that there is no need to install special mobile phone holders in the car. Not only can a call be answered via Bluetooth, but it can also be dialed and navigated. Useful additional information such as the number of the caller or his name is also transferred from the mobile phone address book to the car radio via Bluetooth. Hands-free systems outside the car also work via Bluetooth. Headsets that are connected via Bluetooth can often also answer incoming calls using a corresponding button.

The support of such control functions (e.g. activation of the voice assistant on the smartphone) varies greatly with the devices used and depends on the manufacturer chips, resp. their programming according to the possibilities of the corresponding Bluetooth protocol stack.

Playground equipment

The toy industry uses this technique to allow dolls and toy animals to communicate and interact with each other.

The controllers of the Nintendo Wii / Wii U / Switch, PlayStation 3 / PlayStation 4, Xbox One S / Xbox One X, Lego Mindstorms EV3 and the Ouya also use Bluetooth to communicate with the console.

communication

Bluetooth hotspots as radio cells enable cordless access to a network, such as the Internet or a company LAN. Audio devices without Bluetooth, in particular older cell phones and landline phones, can be expanded to include Bluetooth via a connected adapter. In recent years, many manufacturers ^{[32] [33] [34] have} increasingly used Bluetooth, especially for motorcycle intercom systems, with ranges of up to 1.6 km. ^[35] Particular advantages are very small sizes and the absence of annoying cables. Universal additional factors for two-factor authentication can also communicate with operating systems or web browsers via Bluetooth, such as security tokens for the open U2F standard of the FIDO alliance.

Industry

Due to the adaptive frequency hopping (AFH) method used, Bluetooth offers a very reliable and interference-resistant radio connection. This advantage of Bluetooth over other radio technologies was recognized early on by various manufacturers of automation products (e.g. Phoenix Contact, WAGO Kontakttechnik GmbH & Co. KG, Schildknecht AG). As a result, Bluetooth-based industrial products were developed that are used in a wide variety of areas of industry to communicate wirelessly between different components in machines. In the meantime, the PROFIBUS User Organization e. V. (PNO) Bluetooth is defined alongside WLAN as the carrier method for wireless transmission of PROFINET data packets at the fieldbus level. At the sensor / actuator level, 802.15.1 was also used as carrier technology in the PNO standard WSAN-FA, but with a different protocol stack. ^[36] The CAN in Automation (CiA) association also plans to specify a Bluetooth-based system for the wireless transmission of CAN telegrams. Overall, the standardization efforts underpin the suitability of Bluetooth for industrial automation.

House technic

In the field of home automation and alarm systems, there are products that use Bluetooth 2.0.

Another application is Bluetooth as a key, for which any Bluetooth-capable device can be used as a key. No additional software is required on the devices (mobile phones) for this.

Medical technology

In orthopedic technology, Bluetooth is used to adjust modern arm and leg prostheses. Settings such as stance phase damping and maximum load can be made via Bluetooth.

Hearing aids in higher price ranges are also available with Bluetooth receivers. This means that the signals from mobile phones and audio devices can be selectively transmitted to the hearing aid via a transponder without environmental distortions. The transponder communicates via Bluetooth and transmits the information into the radio area of the hearing aids. ^[37]

With some insulin pumps, Bluetooth serves as an interface for communication with a blood glucose meter, a remote control or a personal computer.

Remarks

"HID Proxy Mode" for computers without Bluetooth support

The Bluetooth input devices are usually only available when the operating system and its Bluetooth stack are loaded. As a result, it is not possible to use a Bluetooth keyboard e.g. For example, make settings in the BIOS or in the UEFI settings menu before loading the operating system, or wake the PC from the S4 sleep mode using the "Wake up on Keyboard" function or switch it on from the switched-off mode. In addition, retrofitting a Bluetooth interface is not possible with some systems for various reasons. This includes many smart TVs, many microcontroller boards, NAS systems, rack servers.

Some Bluetooth adapters overcome these problems with the "HID Proxy Mode". By means of a microcontroller, such adapters themselves provide a Bluetooth stack for Bluetooth input devices. These devices can connect to the Bluetooth adapter before loading the operating system and can thus be used for the wake-up-on-keyboard function or changes in the BIOS or in the UEFI settings menu. The Bluetooth adapter presents itself to the BIOS and the UEFI firmware as a normal USB HID input device. It transfers the BT functionality to the operating system as soon as its Bluetooth driver and Bluetooth stack are loaded, which means that other Bluetooth devices can also be used in addition to Bluetooth input devices. ^{[38] [39]}

The UEFI firmware could also itself provide a Bluetooth stack for Bluetooth input devices, so that Bluetooth input devices can already be used in the UEFI menu even without HID proxy mode support. However, a concrete implementation of a Bluetooth stack for the UEFI firmware of motherboards is not yet known.

Router

tә(r)]) oder Netzwerkrouter sind Netzwerkgeräte, die Netzwerkpakete zwischen mehreren Rechnernetzen weiterleiten können. Sie werden am häufigsten zur Internetanbindung, zur sicheren Kopplung mehrerer Standorte (Virtual Private Network) oder zur direkten Kopplung mehrerer lokaler Netzwerksegmente, gegebenenfalls mit Anpassung an unterschiedliche Netzwerktechniken eingesetzt (Ethernet, DSL, PPPoE, ISDN, ATM etc.).Router (['ru: tә (r)] or [' ra

tә (r)]) or network routers are network devices that can forward network packets between several computer networks. They are most often used for Internet connection, for the secure coupling of several locations (virtual private network) or for the direct coupling of several local network segments, possibly with adaptation to different network technologies (Ethernet, DSL, PPPoE, ISDN, ATM etc.).

Routers make their forwarding decisions based on information from network layer 3 (for the IP protocol this is the network part in the IP address). Many routers also translate between private and public IP addresses (Network Address Translation, Port Address Translation, NAT / PAT) or map firewall functions using a set of rules.

The routers designed to connect home networks to the Internet are also called Internet routers.

Routers work on layer 3 (network layer) of the OSI reference model. A router has at least one interface (English interface) that connects networks. Interfaces can also be virtual if they are e.g. B. can be used to mediate data between virtual networks (VLAN). When data packets arrive, a router must use the OSI layer 3 destination address (e.g. the network portion of the IP address) to determine the best route to the destination and thus the appropriate interface via which the data is to be forwarded. To do this, he uses a locally available routing table, which specifies which connection of the router or which local or remote router can be used to access which network.

• • direkt mit der Schnittstelle verbundene Netze: Sie werden automatisch in eine Routingtabelle übernommen, wenn ein Interface mit einer IP-Adresse konfiguriert wird und dieses Interface aktiv ist („link up“).
• • statische Routen: Diese Wege werden durch einen Administrator eingetragen. Sie dienen zum einen der Sicherheit, sind andererseits nur verwaltbar, wenn ihre Zahl begrenzt ist. Die Skalierbarkeit ist für diese Methode ein limitierender Faktor.
• • dynamische Routen: In diesem Fall lernen Router erreichbare Netze durch ein Routingprotokoll, das Informationen über das Netzwerk und seine Teilnehmer sammelt und an die Mitglieder verteilt.

Routers can learn paths in three different ways and use this knowledge to create the routing table entries.

• • Networks directly connected to the interface: They are automatically transferred to a routing table if an interface is configured with an IP address and this interface is active ("link up").
• • Static routes: These routes are entered by an administrator. On the one hand, they serve security, on the other hand, they can only be managed if their number is limited. Scalability is a limiting factor for this method.
• • Dynamic routes: In this case, routers learn accessible networks through a routing protocol that collects information about the network and its participants and distributes it to the members.

The function of the routing table is comparable to that of an address book, in which it is looked up whether a destination IP network is known, i.e. whether there is a way to this network and, if so, which local interface the router uses to transmit the data to it should. The routing decision is usually made based on the significance of the entries; more specific entries are chosen before less specific ones. An existing default route represents the least specific route, which is then used if there is no specific entry for the destination (network) beforehand. When referring to the entire Internet routing table as part of the Inter-AS routing, it is common not to keep a default route.

Some routers speak English Policy Based Routing (for strategy-based routing). The routing decision is not necessarily made on the basis of the destination address (OSI layer 3), but other criteria of the data packet can also be taken into account. These include, for example, the source IP address, quality requirements or parameters from higher layers such as TCP or UDP. For example, packets that transport HTTP (web) can take a different route than packets with SMTP content (mail).

Routers can only process data packets suitable for routing, i.e. from routable protocols such as IP (IPv4 or IPv6) or IPX / SPX. Other protocols, such as the NetBIOS and NetBEUI originally used by MS-DOS and MS-Windows, which were only intended for small networks and are not routable by design, are not forwarded by a router by default. However, it is possible to transmit such data to tunnels and corresponding functions, such as data link switching (DLSw), to remote routers and deliver them to the destination there. Packets from these protocol families are usually processed by systems working on layer 2, i.e. bridges or switches. Professional routers can perform these bridge functions when required and are called layer 3 switches. As a layer 3 system, all layer 2 functions end at the router, including the broadcast domain. This is particularly important in large local networks in order to keep the broadcast volume low for the individual participants in a subnet. However, if broadcast-based services, such as DHCP, are to function across the router, the router must provide functions that receive these broadcasts, evaluate them, and then route them to another system for processing (relay agent function).

A distinction must also be made between single and multi-protocol routers (also multi-protocol routers). Single protocol routers are only suitable for a network protocol such as IPv4 and can therefore only be used in homogeneous environments. Multiprotocol routers master the simultaneous handling of several protocol families, such as DECnet, IPX / SPX, SNA, IP and others. Today IP routers dominate the field, since practically all other network protocols have only a subordinate meaning and, if they are used, can often also be encapsulated (NetBIOS over TCP / IP, IP-encapsulated IPX). In the past, multi-protocol routers were essential in larger environments, at that time many manufacturers used different protocol families, so it was essential that the router supported several protocol stacks. Multiprotocol routers are found almost exclusively in long-distance or ATM networks.

It is important to differentiate between the routed protocols (such as Internet Protocol or IPX) and routing protocols. Routing protocols are used to manage the routing process and the communication between the routers, which thus exchange their routing tables (for example, BGP, RIP or OSPF). Routed protocols, on the other hand, are the protocols that underlie the data packets that the router transports.

Types (designs)
Backbone router, hardware router
Avaya ERS-8600

The high-speed routers (also carrier-class routers) on the Internet (or for large companies) are today devices that are highly optimized for forwarding packets and can route many terabits of data throughput per second in hardware. The required computing power is largely provided decentrally by special network interfaces, a central processor (if any) is not or only very little used. The individual ports or interfaces can receive and send data independently of one another. They are either connected via an internal high-speed bus (backplane) or crosswise with one another (matrix). Such devices are usually designed for continuous operation (availability of 99.999% or higher) and have redundant hardware (power supplies) to avoid failures. It is also common to be able to replace or expand all sub-components during operation (hot plug). In the early days of computer networking, on the other hand, it was common to use standard workstations as routers in which routing was implemented by software.

Border router

A border router or edge router is mostly used by Internet service providers. It must connect the networks of the subscriber who operates it with other peers (partner routers). The routing protocol BGP predominantly runs on these routers.

The EBGP (External Border Gateway Protocol) protocol is usually used for communication between the peers, which enables the router to transfer data to a neighboring autonomous system.

To prioritize their own network traffic, operators often use type of service routing and methods for monitoring the quality of service (QoS).

High-end switches

For some manufacturers (for example, at Hewlett-Packard), the high-speed routers (including carrier-class routers, backbone routers or hardware routers) cannot be found under their own router section. Routers are marketed there together with the better equipped switches (Layer 3 switch and higher, Enterprise Class). This is logical insofar as switches from the upper middle class range practically always master the routing functionality. Technically, these are systems that, like the devices referred to as routers, rely heavily on the forwarding of packets (router: based on the OSI layer 3 address as the IP address, switch: based on the OSI layer 2 address , the MAC address) are optimized and offer many gigabit data throughput per second. They are configured via the management interface and can either work as a router, switch and, of course, in mixed operation. Financially, the boundaries between the two device classes are becoming increasingly blurred in this area.

Software router

Instead of special routing hardware, ordinary PCs, laptops, nettops, Unix workstations and servers can be used as routers. The functionality is taken over by the operating system and all computing operations are carried out by the CPU. All POSIX-compliant operating systems master routing by default, and even MS-DOS could be expanded with routing functionality using the KA9Q software from Phil Karn.

Windows also offers routing services in all NT-based workstation and server versions (NT, 2000, XP, 2003, Vista, 7). The server version of Apple's Mac OS X contains router functionality.

In addition to the built-in, basic routing functions, the free operating system OpenBSD (a UNIX variant) offers several advanced routing services, such as OpenBGPD and OpenOSPFD, which can be found in commercial products. The Linux kernel contains extensive routing functionality and offers many configuration options, commercial products are nothing more than Linux with proprietary in-house developments. There are entire Linux distributions that are particularly suitable for use as routers, for example Smoothwall, IPCop or Fli4l. OpenWrt is a special case, this allows the user to create firmware that runs on an embedded device and can be configured via SSH and HTTP.

The main disadvantage of PC-based software routers is their high power consumption. In the SoHo area in particular, electricity costs are higher than the price of an embedded device within one year.

DSL router

A router that includes a PPPoE client for dialing into the Internet via xDSL of an ISP and currently masters Network Address Translation (NAT) in IPv4 networks for converting a public IPv4 address to the various private IPv4 addresses of the LAN is known as DSL router. These DSL routers are often equipped as multifunction devices with a switch, a WLAN access point, not infrequently with a small telecommunications system, a VoIP gateway or a DSL modem (any type of xDSL).

Firewall functionality in DSL routers

Almost all DSL routers are now NAT-capable, which means that they are able to translate network addresses. Because a connection from the Internet to the network behind the NAT router is not easily possible, this functionality is already referred to by some manufacturers as a NAT firewall, although the protection level of a packet filter is not achieved. ^[1] The lock can be bypassed by configuring port forwarding, which is necessary for some virtual private network or peer-to-peer connections. In addition, most DSL routers for private use have a rudimentary packet filter, some of which are stateful. These packet filters are used with IPv6. Due to the elimination of NAT, port forwarding again becomes a simple release of the port. Many routers in this (consumer) class Linux are used as the operating system and iptables are mostly used as firewalls. Such products usually do not contain a content filter. A safe alternative is free firewall distributions based on probably more secure operating systems, for example OPNsense.

Protective measures for DSL and WLAN routers

If programming errors are discovered, a router manufacturer can provide a new software update to improve it or to close security gaps. If the router is not brought up to date, you also endanger your own network security. It is therefore essential to protect personal data that a software update is carried out at regular intervals.

• • nur aktuelle WLAN-Verschlüsselungen (WPA2) verwenden - WEP-verschlüsselte Zugänge können binnen weniger Minuten entschlüsselt werden
• • vom Hersteller vorgegebene Passwörter ändern, nur sichere Passwörter wählen
• • die SSID umbenennen
• • Deaktivieren von WPS und der Fernadministration
• • keine Netzwerkports willkürlich und unüberlegt öffnen
• • Deaktivieren von UPnP-Funktionen, die beliebiger Software das Öffnen von Netzwerkports ermöglicht
• • Absichern von Diensten, die per Portweiterleitung aus dem Internet erreicht werden können
• • eine leistungsfähige (dedizierte) stateful-Firewall wie pfSense oder OPNsense (letztere mit ASLR und LibreSSL) mit einem reinen DSL-Modem^[2][3]

Other measures to protect routers:

• • Use only current WLAN encryption (WPA2) - WEP-encrypted access can be decrypted within a few minutes
• • Change passwords specified by the manufacturer, only choose secure passwords
• • rename the SSID
• • Disable WPS and remote administration
• • do not open any network ports arbitrarily and without thinking
• • Disable UPnP functions that allow any software to open network ports
• • Securing services that can be accessed via port forwarding from the Internet
• • a powerful (dedicated) stateful firewall such as pfSense or OPNsense (the latter with ASLR and LibreSSL) with a pure DSL modem ^{[2] [3]}

WLAN router

The combination of wireless access point, switch and router is often referred to as a WLAN router. This is correct as long as there are ports for connecting at least a second network, usually a WAN port. The routing takes place between the at least two networks, usually the WLAN and WAN (and if available between LAN and WAN). If this WAN port is missing, it is only a matter of marketing terms, since pure access points work at OSI level 2 and are therefore bridges and not routers. WLAN routers are often not fully functional routers, they often have the same restrictions as DSL routers (PPPoE, NAT). With IPv6, NAT is not required for these devices, only in the transition phase does the router have to master additional tunnel protocols such as 6to4.

Automation routers

With the penetration of network technology in industrial automation, modem routers with external access via telephone and mobile phone connections are increasingly being used. Industrial devices are software routers based on embedded Linux, which are optimized not for high throughput, but for mechanical robustness, mounting in the control cabinet and durability.

Software or hardware router

In general, software routers perform valuable and extensive services mainly in a non-professional environment. In general, there are two different types of implementation for software routers, firstly a dedicated router, whereby a PC, a workstation or a server is used almost exclusively as a router used (often as a DHCP, DNS server or firewall); on the other hand, non-dedicated routers, here a server takes over the routing in addition to its existing tasks. Both systems are well suited for the non-performance-critical area and can compete with professional solutions, especially in terms of costs, in terms of performance they are usually inferior.

One of the reasons for this is that such systems have so far often been based on a classic PCI bus with a 32-bit bus width and 33 MHz clock rate (PCI / 32/33). Theoretically, 1 GBit / s (1000 MBit / s, corresponds to approximately 133 MByte / s) can be routed via such a bus in half-duplex mode (HDX); since the network packets pass the PCI bus twice in this case (card-PCI main memory-CPU main memory-PCI card), the maximum routable data stream of a software router based on it is reduced to about 0.5 GBit / s. Today, Ethernet is almost always switched and operated in full-duplex FDX mode, which means that, for example, Gigabit Ethernet, even though names such as 1 GBit / s Ethernet, 1GbE or 1000BASE-T suggest otherwise, can already handle 2 GBit / s (1GbE each in any direction). It follows that a system based on PCI / 32/33 cannot reach the maximum transmission rate of 2 GBit / s theoretically possible on the network side. Systems with a PCI / 64/66 bus can achieve about 4 GBit / s on the bus side, just enough for the peak load of two 1GbE interfaces in FDX mode. Even higher quality classic (legacy) server systems have faster interfaces (PCI-X 266 or better), as well as several independent PCI buses. You can easily achieve higher throughput rates, but typically have high energy consumption. Why, especially in dedicated router operation, is the cost-benefit question. Hardware routers with specialized CPUs and application-specific chipsets (application-specific integrated circuit for short ASIC) make this much more energy efficient.

Only with the introduction of PCI Express (with 2 GBit / s in version 1.x and 4 GBit / s per lane in version 2.x in FDX mode - and more) does an adequate peripheral transfer performance also exist for standard PCs Several 1GbE connections (also 10GbE) are available, so that energy-efficient, high-throughput software routers can be built from inexpensive standard hardware. Since all values have so far been theoretical and in practice not only data has to be routed through the bus, but routing decisions have to be made, a software router may continue to lose performance. In practice, only half of the theoretically possible data throughput should be assumed. At such data rates, at least the cost-performance ratio is good and sufficient with a software router.

Hardware routers from the high-end sector, as they can have special high-performance buses or "cross bars", are clearly superior in performance - which is also reflected in the price. In addition, these systems are designed for fail-safe continuous operation (availability of 99.999% and higher). Simple PCs cannot keep up, high-quality servers and workstations also have redundant components and a high level of reliability for many applications.

Some so-called hardware routers actually consist of PC components. Only the housing or the partly mechanically modified PCI slots and the "cryptic" operating system give the impression that they are special systems. Although these systems usually work very robustly and reliably, the routing is carried out by software.

Routing cluster

In order to be able to route 1GbE or 10GbE networks, for example, a high-priced hardware router is not absolutely necessary. Provided there is a slight loss in transmission speed, routing clusters can be used. This can be made up of one software router (e.g. as a workstation with two PCI Express 10GbE LAN cards) per Ethernet line. The software routers are connected to one another via a professional switch with a sufficient number of ports and a correspondingly high throughput rate (a few hundred Gbit / s). In contrast to networks with a central backbone, the maximum data throughput rate of the entire routing cluster corresponds to the maximum throughput rate of the central switch (a few hundred Gbit / s). Optionally, the clusters can be designed redundantly (via high-availability Unix or HA Linux). Such cluster systems do take up a relatively large amount of space and do not achieve the performance and reliability of high-speed routers, but they are highly modular, well scalable, comparatively performant, and yet inexpensive. They are used where costs are valued higher than performance, for example in schools or universities.

Li-fi

Li-Fi (English light fidelity) is a term coined in 2011 by the German researcher Harald Haas working at the University of Edinburgh for a method of optical data transmission over short distances (English Visible Light Communications, VLC) and an optical equivalent to the wirelessly implemented WLAN .

History and state of research

In October 2011, four founding members, the Norwegian IBSENtelecom, the Israeli-American Supreme Architecture, TriLumina (USA) and the Fraunhofer Institute for Photonic Microsystems agreed to form a Li-Fi consortium to promote this standard. ^[1]

By switching special light-emitting diodes (LEDs) on and off, high data transmission rates can be achieved for short-range optical communication: in 2013, 10 gigabits per second were achieved in the laboratory. ^[2] The photodiodes act as receivers in which the light signals are converted into electrical pulses. In the meantime, speeds of around 224 gigabits per second have already been reached under laboratory conditions.

Oledcomm presented the first Li-Fi compatible mobile phone at the Consumer Electronics Show 2014. ^[3]

At the end of 2015, Harald Haas presented an improved and more efficient version of Li-Fi, in which a photovoltaic cell is used to collect and process the light signals. With this version, energy is now also recovered and new application possibilities are created.

Advantages and disadvantages

Compared to radio transmission, a larger bandwidth is available due to the optical transmission, which theoretically allows a higher number of data channels in the same space. In addition, this transmission method can also be used in areas where radio signals can be problematic due to their electromagnetic compatibility, for example in airplanes or hospitals. Furthermore, the use of optical transmission is more secure, since an attacker would have to have physical access to the light source in order to intercept or manipulate data packets.

In contrast to radio systems, only direct data transmission is usually possible with optical transmission and data transmission through, for example, house walls is not possible. With Li-Fi equipment, this may require the installation of fixed receiving and transmitting stations. However, with the latest 5G technology in the 30 GHz range, a transmitter is also required in every room, which is why fixed receiving and transmitting stations are no longer an exclusive disadvantage of Li-Fi.

microelectronics

Microelectronics is a branch of electronics, more precisely semiconductor electronics, and microtechnology. Microelectronics deals with the design, development and manufacture of miniaturized electronic circuits, today mainly integrated circuits. These semiconductor-based circuits use many electronic components, such as those used in normal electronic circuits, for example transistors, capacitors, diodes and resistors.

In the history of integrated microelectronics, various circuit families (TTL, CMOS etc.) have emerged, which differ with regard to the functional principles used (e.g. bipolar and unipolar components / transistors) and the associated circuitry properties (power requirement, switching speed etc.). Thanks to new design and manufacturing processes, users now have the option of having standard circuits (microcontrollers, memory modules, etc.) also profitably manufacture and use special application-specific integrated circuits (ASIC)

Features of microelectronics

Microelectronic circuits are distinguished from conventional electronic circuits by two main features: integration and miniaturization.

Integration is the combination of all components (transistors, but also resistors, capacitors and other semiconductor components) and wiring to form an electronic circuit on a common substrate. In the case of microelectronic circuits, these are also manufactured in a joint work process.

In this context, miniaturization means that the individual components (and thus the circuit as a whole) are continuously reduced in size. In the beginning, the dimensions for the most important component, the transistor, were still over ten micrometers. Contrary to this are the dimensions of transistors (physical gate length) of less than 30 nm (2017 approx. 30-24 nm for Intel or Samsung's 14 nm FinFET technology ^[1] ). This miniaturization enables integrated circuits with more than one billion transistors ^[2] to be implemented on a piece of silicon with an edge length of a few (typically <10) millimeters. In addition, the smaller distance between the components allows the circuits to be operated at higher clock frequencies and the electrical power required to be increased only slightly despite the higher computing power.

Before the invention of integrated circuits, there were also intensive efforts to miniaturize. Circuits with voluminous electron tubes have been reduced to such an extent by the development of battery tubes that, for example, portable radio devices have become possible. The introduction of the transistors brought a further miniaturization step, with thick-film circuits as the smallest version before the integrated circuits.

Miniaturization of integrated circuits

The main driving force behind the downsizing of the structures is the reduction in manufacturing costs. Microelectronic circuits are manufactured in batch production on semiconductor wafers of a certain size (4 inches to 12 inches).

Several hundred to a thousand chips are produced on a wafer at the same time. The manufacturing costs are mainly dependent on the number of chips per wafer, the sum of the costs for the structuring and property-changing processes and the production yield.

The number of chips per wafer can be achieved by reducing the size of the structures (transistor sizes, interconnects, etc.). In order to obtain approximately the same electrical properties, all dimensions of the chip (length, width and also layer thicknesses) must be scaled equally. The number of chips increases (approximately) with the square of the scaling factor (the area reduction is equal to the reduction in length dimension to the square plus better edge utilization minus non-linear effects), i.e. half chip lengths (scaling factor 2) quadruple the number of chips with the same wafer size.

However, the costs of the structuring processes usually increase with miniaturization. The reason for this lies on the one hand in the increasing complexity of the circuit and the associated increasing number of necessary process steps, on the other hand in higher demands on the manufacturing process itself (tolerances, more complex manufacturing processes etc.).

A further reduction in costs was achieved with larger wafers. In the early years, manufacturers still used wafers with a diameter of 2 or 3 inches (corresponding to about 51 or 76 mm). Today (2009), however, standard industrial wafers have a size of 200 millimeters, some manufacturers such as AMD and Intel even use 300 mm wafers. In accordance with the enlargement of the wafer area, the number of chips per wafer also increased. The manufacturing costs per wafer, however, increased only comparatively slightly despite increased requirements, so that the total costs could be reduced. A corresponding changeover, however, requires enormous investments in the production facilities.

Gordon Moore formulated the facts of the permanent

Manufacturing costs were reduced as early as 1965 - in the early stages of microelectronics - according to his regularity by saying that the number of transistors on a chip doubled every twelve months (later eighteen months). Since then, microelectronics have indeed made steady progress, both in terms of integration density and in reducing the size of structures.

The high, constant reduction in manufacturing costs in microelectronics has been a major driver of innovation in the past thirty years in a large number of industries - and not just in electronics and computer technology (see Applications section).

Whether this trend can be maintained is considered uncertain given the increase in process costs when physical limits are approached and their compensation by saving chip area. In addition, some special circuit technologies can no longer be scaled down, such as those to achieve higher voltages than the supply voltage (s) of the chip.

Consequences of miniaturization

The miniaturization of integrated circuits has other effects besides the cost reduction for equivalent products.

Smaller transistors enable higher switching frequencies. Together with shorter conductor tracks, this leads to shorter signal delays. As a result of the reduction in the size of the structures, faster and thus more powerful circuits are possible. However, there are also opposite effects. As described in the previous section, the miniaturization also reduces the layer thicknesses in the metallization (interconnects and intermediate insulation). The shortened distances between the conductor tracks lead to higher coupling capacities, which act as a delay brake (cf. RC link).

The layer reduction of the gate insulation layer has a positive effect. The transistors can be operated at a reduced voltage and thus have a reduced power loss (the power loss per area increases, however → poorer heat dissipation). Furthermore, higher system integration (more functions on one chip) means fewer components on a circuit board and thus increased reliability due to fewer solder connections. Without downsizing and integration, battery-powered, mobile electronics would be inconceivable, as is ubiquitous today: cell phones, notebooks, PDAs, etc.

History, development and people of microelectronics

prehistory

Microelectronics is often associated with, or even equated with, computer technology, in particular the widespread use of integrated circuits in the form of processors and microcontrollers in almost all areas of modern life has contributed to this. However, electronic calculating machines already existed a few decades before the first transistors or integrated circuits.

The first electromechanical computers - for example Colossus or Mark I - were created in the Second World War in the early 1940s (see History of Computers). The ENIAC (Electronic Numerical Integrator and Calculator) mainframe, which went into operation in 1946, was the first universal, purely electronic computer. However, these first calculating machines cannot be compared with today's personal computers in terms of computing power or size.

What the transistor is for today's microelectronic circuits was the electron tube for the 27 ton ENIAC, which consisted of 17,468 electron tubes and is one of the tube computers. The basics of the electron tube go back to the discovery of the glow emission (1883) by Thomas A. Edison (see history of the electron tube). The first electron tube, a tube diode, was developed in 1904 by John Ambrose Fleming and modified in 1906 by Lee de Forest. Forest added a third electrode to the tube diode, creating the triode tube, the equivalent of tube electronics to the transistor.

As an alternative to digital computers, analog and hybrid computers were available until the 1970s, which were used primarily to calculate differential equations. For example, the Rockefeller Differential Analyzer worked with thousands of electron tubes and electrical relays and was the most powerful calculator until the end of World War II.

The use of a large number of electron tubes in complex devices was countered by some disadvantages of these components. Electron tubes were relatively prone to errors, required a warm-up time and had quite high power losses. To the main improvement goals of the developers after the Commissioning the first electronic calculating machines therefore included increased reliability and a reduction in manufacturing costs.

Miniaturization was also an important topic, after all, the first calculating machines filled entire rooms. However, electron tubes are hardly miniaturizable. Nevertheless, there have already been intensive efforts to miniaturize both the structure of the overall circuit and the tubes themselves. Circuits with voluminous electron tubes have been reduced to such an extent by the development of battery tubes that, for example, portable radio devices have become possible. The introduction of the transistors brought a further miniaturization step, with thick-film circuits as the smallest version before the integrated circuits.

An early form of computer memory was core memory, which used many hard magnetic rings threaded on wires that could be remagnetized and read out by means of a current surge.

Invention of the transistor

The fact that the computing power of the mainframe at that time can no longer keep up with that of today's pocket calculators is largely thanks to the development of the transistor based on the so-called semiconductors and integrated circuits.

The discovery of the transistor or the transistor effect is generally attributed to the American scientists John Bardeen, Walter Brattain and William B. Shockley. They received the Nobel Prize in Physics in 1956 "for their studies on semiconductors and their discovery of the transistor effect". Bardeen, Brattain, and Shockley were part of a Bell Telephone Laboratories group in Murray Hill, New Jersey, that investigated field effects in solids. In one of the experiments carried out on December 16, 1947, Brattain observed a current gain, the transistor effect. ^[3] The construction of a three-electrode contacted with the n-doped germanium crystal was the first bipolar transistor functioning. The main change compared to previous designs was that two electrodes were very close to each other (approx. 50 µm), which made the transistor effect possible. This transistor, which later became known as the tip transistor, could not be produced reproducibly and its mode of operation was not well known for a long time. Nevertheless, the potential of this discovery was quickly recognized by those responsible. The main advantages over the electron tube were that no vacuum and no warm-up time were necessary and that no heat development was observed. ^[4] The possibilities of miniaturization of electronic circuits was the starting point of a revolution in electronics, the many developments in microelectronics and computer technology has allowed only.

From today's perspective, Bardeen, Brattain and Shockley were not the first or only researchers to develop alternatives to semiconductor-based electron tubes. Already 1925 (Lilienfeld ^[5] ), 1934 (Heil ^[6] ) and 1945 (Heinrich Welker ^[7] ) ideas for another transistor, the field effect transistor, were published. Since the manufacturing processes (e.g. for cleaning the semiconductor substrates from foreign substances) were not sufficient at the time, these ideas could not be realized. For this and other reasons, they were ignored by the public and were known to only a few experts.

The aspect of substrate material is often neglected in connection with the discovery of the transistor. The quality and purity of the semiconductors used is essential for the functioning of transistors. To produce semiconductor crystals with a sufficiently high purity was a big problem at that time (before 1950). Many of the germanium crystals used by the Bell Telephone Laboratories (BTL) group came from WG Pfann, JH Scaff and HC Theuerer. They were manufactured using a zone melting method by GK Teal and JB Little. ^[8th]

Independent of the BTL working group, Herbert F. Matare and Heinrich Welker - then employed at Westinghouse in Paris - developed a transistor that worked on a similar principle. ^[9] This is also referred to as "Transitron" bipolar, they (13 August 1948) presented a few months later than the Americans. ^[10] Matare founded in 1952 in Germany to present the company Inter Metal and was already the first prototype transistor radio with headphones; a year before the first commercial U.S. model. ^[11]

William Shockley opened a Shockley Semiconductor Laboratory in Mountain View near Stanford University in Palo Alto in 1956. ^[12] The laboratory is considered to be a germ cell of Silicon Valley, it should be noted that were very heavily concentrated at that time both research and industry on the East Coast of the United States. As early as September 1957, eight employees (Eugene Kleiner, Jay Last, Victor Grinich, Jean Hoerni, Sheldon Roberts, Julius Blank, Gordon E. Moore and Robert N. Noyce) left Shockley due to differences of opinion. They founded Fairchild Semiconductor Corporation with venture capital. Fairchild Semiconductor was one of the companies that advanced the development of microelectronics at that time, so Fairchild already produced the first silicon-based transistor in volume production in 1958 and was significantly involved in the development of the planar transistor and the integrated circuit. Gordon Moore and Robert Noyce then founded Intel in 1968, which today (2010) is the top-selling company in the field of microelectronics.

Silicon displaces germanium

Silicon became the dominant semiconductor material from the mid-1960s, although germanium was a leader in the early years of semiconductor electronics. In 2009, around 95% of all microelectronic circuits were produced on the basis of silicon.

The initial advantages of germanium were its better properties, such as a lower melting point and higher charge carrier mobility (enables higher switching frequencies), and until then it was easier and easier to clean than silicon.

The most important reasons for the success of silicon are the good properties of the combination of silicon and silicon dioxide. Silicon dioxide is used as an insulation material and, in addition to the good electrical properties (breakthrough field strength, band gap, etc.), shows very good layer adhesion on silicon. With the thermal oxidation of silicon, there is also a simple method of manufacturing silicon dioxide layers on crystalline silicon, which enables silicon dioxide layers with very good interface properties, such as a low concentration of interface charges. Unlike germanium dioxide, silicon dioxide is chemically stable to water, which means that it does not dissolve in water. This enables the surfaces to be easily cleaned with water and the use of various wet-chemical coating or structuring processes. The higher melting point compared to germanium makes the material generally more robust and allows higher temperatures during production, for example in some diffusion and coating processes.

The good properties of thermally produced silicon dioxide enabled the development of the planar process and thus the development of integrated circuits as are used today (see below). These important inventions in microelectronics were preceded by further significant improvements in the manufacture and stability of transistors through the use of thermally produced silicon dioxide. In addition to its suitability as a selective doping mask ^{[13] [14]} , this primarily includes the passivating effect and the very good electrical properties of the interface between thermal silicon dioxide and silicon. The passivation of the surface and the associated reduction in interfacial charges and environmental influences improved the electrical characteristics of the transistors (their characteristics) both in terms of reproducibility and their stability in use. In addition, the improved isolator-semiconductor interface now made it possible to produce the first functioning MIS field effect transistors (MIS-FET). ^{[10] [15] [16] [17]} After it was recognized that charges in silicon dioxide caused by alkali metal impurities also massively impair the electrical properties of semiconductor components ^[18] and this was taken into account in production, the fundamental problems in the production of stable components based on semiconductors solved.

Integrated circuits

The last step to microelectronics was the transition from circuits made of discrete semiconductor components on a printed circuit board to integrated circuits (ICs). Integrated circuits are generally circuits made of semiconductor components (mainly transistors) including the wiring on a substrate, also known as a monolithic circuit . This concept was independently invented in the late 1950s by Jack Kilby ^{[19] [20]} , an employee of Texas Instruments, and Robert Noyce ^[21] , a founding member of Fairchild Semiconductor, and patent applied for. Kilby's patent from 1959 showed for the first time a circuit consisting of various components (transistors and resistors) on a single substrate (made of germanium). From this work emerged the famous Kilby patent ^{[19] [20]} (from the Japanese Patent Office and through the High Court (OG) Tokyo due to the lack of one inventive step rejected. ^[22] ). This patent was contested in court for around ten years because Robert N. Noyce had devised a very similar step, but later applied for a patent. ^[21]

Unlike Kilby, who only thought up wiring on the substrate, Noyce's patent was based on the ideas and knowledge of the planar process, which was also developed by Jean Hoerni (also Fairchild Semiconductor). Photolithographic and diffusion processes that Fairchild Semiconductor had recently developed for the production of the first modern diffusion bipolar transistor had already been used for the production. ^{[23] [24] [25]} Among other things, the technical feasibility of such wiring revolutionized the manufacture of electronic circuits. As a result, many companies intensified their research and development in this area and there was an enormous miniaturization.

The first commercially available integrated circuit was introduced in 1961. It was a flip-flop from Fairchild Semiconductors, was manufactured using planar technology and consisted of four bipolar transistors and five resistors. ^{[26] [27]} The bipolar transistors were quickly replaced by field effect transistors (FETs), mostly in the form of easier-to-manufacture MOSFETs (metal oxide semiconductor field effect transistors). The principle of operation of the MOSFETs had been known for a few decades, but the production of the first functional examples was only possible in 1960 by Martin M. Atalla and Dawon Kahng (cf. surface passivation in the article Thermal Oxidation of Silicon). Other important developments in the 1960s were the CMOS technology (Frank Wanlass, 1963 ^{[28] [29]} ) and the first DRAM memory cell by Robert H. Dennard (Thomas J. Watson Research Center / IBM, 1967 ^[30] , see DRAM).

The complexity of the circuits increased rapidly and in 1970/71 the first microprocessors from three companies were introduced almost simultaneously: the Intel 4004, the Texas Instruments (TI) TMS 1000 and the Garrett AiResearch "Central Air Data Computer" (CADC). At that time, circuits with transistor densities with several thousand components were realized on a chip. This stage of development is known as large scale integration (LSI). Due to the rapid development of microelectronics, transistor densities were achieved in 1979, which were many times larger (around two orders of magnitude) than with LSI circuits. This level of ICs is called Very Large Scale Integration (VLSI). This trend has largely been preserved until today (2009) (see Moore's Law), so that today more than a billion transistors with clock frequencies of several gigahertz are possible. The size of the individual component is well below a square micrometer. Entire systems (combination of several modules, such as processors, interface circuits and memories) are also increasingly being implemented on a single chip (System on a Chip, SoC).

Future developments

If the structure sizes fall below the 100-nanometer limit (in 2008 they were already at 45 nm and in 2009 at 40 nm), one speaks formally of nanoelectronics or nanotechnology (definition by the US government). In the narrower sense, however, it is rather meant that special material properties are used that only occur when the structural dimensions are close to the size of the molecule or atom. Such structures include, for example, conductor tracks or transistors made of carbon nanotubes or insulations made of self-assembling monolayers.

New components are built with resonance tunnel diodes.

Integrated optoelectronics: In view of the increasing signal propagation times, especially in long connection lines (global interconnects) of large "system on a chips", it is being considered to replace these electrical lines with optical connections.

Organic electronics: In order to implement inexpensive "disposable electronics" (for example electronic price labels), circuits based on organic and metallic materials are applied to organic substrates using thin-film technology (see organic field effect transistor).

Interesting perspectives also result from the fact that, due to the progressive scaling, the smallest structures that can be implemented in microelectronics are reaching the size of biological molecules. At the moment there is a convergence of biotechnology and microelectronics and the formation of a new specialist science, which is often referred to as bioelectronics and will primarily affect the development of new biosensors. ^[31]

Classification and components

A large number of semiconductor components (especially diodes and transistors), electrical resistors, capacitors and rarely also inductors are used in microelectronic circuits and integrated, that is to say assembled, on a semiconductor crystal (substrate). The microelectronic circuits can be divided into standard circuits or application-specific standard products (ASSP) and application-specific circuits (ASIC) on the basis of the application area, and analog and digital ICs based on the signals to be processed.

Standard circuits can be used in a large number of applications, are produced in large numbers and some of them are defined by standardization consortia. In contrast, application-specific ICs are circuits that are designed and built for a specific application (for example, engine control in the car) and do not allow any other application with regard to their range of functions. The demarcation of these two groups is fluid in practice: Some circuits, known as ASIC, can still be reprogrammed, but not for any function or application.

Analog ICs are integrated circuits that can directly process analog signals - signals that can change continuously within a certain value range, such as voltages or currents. A large field of application here are so-called standard ICs with low functional integration, for example operational amplifiers and voltage regulators.

Digital ICs, on the other hand, only process digital signals - signals whose value ranges have a finite number of signal values. They currently (2009) represent the largest group of circuits. Typical representatives of digital ICs are programmable logic devices (PLD), memory devices (such as ROM, PROM, DRAM or flash memory) and complex circuits programmable via microcode such as digital signal processors, microcontrollers or microprocessors.

In addition to this rough division into analog and digital ICs, there are other circuits, such as the digital-to-analog or analog-to-digital converters at the interface between the analog and digital range, as well as frequency-voltage converters and voltage-controlled oscillators (voltage Frequency converter). Sensors are also often integrated directly into the microelectronics, often together with their adaptation electronics and possibly a digital interface for connection to a microprocessor. Temperature sensors are relatively simple. Today, large quantities are produced on optical sensors, as image sensors or as parts of optoelectronic arrangements.

The different forms of component integration require different assembly configurations in order to combine the individual components into electronic assemblies. This resulted in a large number of complex and differentiated assembly and connection technologies. ^[32] Components differ according to the assembly configuration in housed SMDs that can be placed on the circuit board or pluggable wired components (THT) and in unhoused bare chips that are placed directly on the wiring carrier or with an intermediate wiring carrier. Today, most components are assembled as SMDs. However, there are components for which no attachable SMD designs are available yet or for which the electrical load capacity of the component is too limited due to the SMD design. In these cases, the older THT designs are still used. ^[33]

Applications

• • In Computern sind essenzielle Bestandteile als mikroelektronische integrierte Schaltkreise ausgeführt: die zentrale Recheneinheit genauso wie der Arbeitsspeicher und eine Vielzahl unterstützender Controller und Schnittstellen-Bausteine.
• • In der industriellen Fertigung finden sich mikroelektronische Bauteile auch zum Beispiel in den Maschinensteuerungen.
• • In Geräten der Unterhaltungselektronik übernehmen integrierte Schaltungen neben der gesamten Steuerung der Geräte auch die Dekodierung komprimierter Filme beim DVD-Abspielgerät oder die Ansteuerung der einzelnen Bildpunkte eines Flachbildschirms.
• • In allen Arten von Fahrzeugen wird die Mikroelektronik eingesetzt, unter anderem zur Motorsteuerung oder dazu, im richtigen Moment Sicherheitsfunktionen, wie Airbags, auszulösen. Für diesen Bereich müssen die mikroelektronischen Bausteine übrigens erhöhte Qualitätskriterien erfüllen, zum Beispiel den automotiven Temperaturbereich (engl. automotive temperature range).
• • Moderne Kommunikationstechnik ist ebenfalls ohne Mikroelektronik nicht mehr denkbar, das gilt sowohl für die klassische Telefonie, als auch für die Datenkommunikation und den Mobilfunk.

Microelectronic components were originally developed for the requirements of space travel for small and light components. They can be found in a variety of technical devices and facilities today:

• • In computers, essential components are implemented as microelectronic integrated circuits: the central processing unit as well as the main memory and a large number of supporting controllers and interface modules.
• • In industrial production, microelectronic components can also be found, for example, in the machine controls.
• • In consumer electronics devices, in addition to the overall control of the devices, integrated circuits also take over the decoding of compressed films on the DVD player or the control of the individual pixels on a flat screen.
• • Microelectronics are used in all types of vehicles, including for engine control or to trigger safety functions such as airbags at the right moment. For this area, the microelectronic components have to meet increased quality criteria, for example the automotive temperature range.
• • Modern communication technology is also no longer conceivable without microelectronics, this applies to classic telephony as well as data communication and mobile radio.

At this point, only an exemplary selection can be mentioned - there are a variety of other applications in the areas mentioned as well as a number of application areas not mentioned here, such as medical technology, building technology and much more.

Development of microelectronic components
Main article: Chip design

Several billion transistors and other basic elements of the microelectronic circuits can be applied to a die, a single unpackaged semiconductor chip. The design of a functional chip is supported with computer-assisted aids. The individual steps that are usually carried out in a division of labor and several times with decreasing abstraction are: design, simulation and verification. The final step is production preparation. Since the production of a chip is preceded by very high non-recurring engineering costs (NRE costs) (e.g. mask costs, see photolithography) and the repair of an integrated circuit is only possible to a very limited extent and is not productively practical, it is very large Meaning that the design leads to the desired product with only a few revisions (so-called redesigns). As a result, simulation and verification steps determine the development process to a considerable extent - in 2004 they accounted for about half of the development effort for the circuit - with an upward trend. In order to distribute these costs over a large number of chips, attempts are made to distribute sub-steps of the development work over several projects. For example, logic gates or entire microprocessor architectures can be purchased as tested libraries and integrated into your own development. Another option is to use FPGAs (digital technology) and FPAAs (analog technology). These components contain freely programmable digital and analog circuits, which only need to be configured according to your own circuit design.

In many cases, the chip developer describes the desired circuit for digital circuit blocks only in a "high-level language" (comparable to the higher programming language in computer science, common forms: VHDL, Verilog), the computer uses this to calculate the switching networks (synthesis) places the transistors (with human participation and control).

For analog circuits, the designed circuits are characterized in a large number of simulation runs (for example with SPICE or similar), with many different combinations for operating temperatures and voltages, process variations and the like being simulated. Statistical variations are also often simulated using a Monte Carlo analysis. For digital and analog circuits, the layout can be extracted to take parasitic elements into account in the simulation and thus achieve more realistic results.

The advancing miniaturization pushes both the structuring processes and the implemented function modules, such as transistors and conductor tracks, to their physical limits. To counter the former, software is increasingly being used in the design process that simulates the physical boundary effects, such as optical diffraction in photolithography, and modifies the circuit design so that these effects are balanced (English: optical proximity correction, OPC). In order to counteract the miniaturization effects in the components, new simulation and modeling methods are continuously added to the chip design process: for example, simulations of the voltage drop in long supply networks (English IR drop), simulation of the parasitic capacitive coupling of adjacent conductor tracks, tools for the static analysis of the time relationships in one Digital circuit (static timing analysis, STA), etc.

In order to manufacture prototypes of a new chip reasonably inexpensively, the layouts of several chips can be put together on a wafer (English: multi project wafer, MPW), since this allows the mask and manufacturing costs for the comparatively small prototype quantities to be distributed over several projects.

Manufacture of microelectronic circuits
→ Main article: Integrated circuit # manufacturing and semiconductor technology

Microelectronic circuits are manufactured using methods from semiconductor technology (manufacture of components on a substrate and, in the case of monolithic circuits, wiring) and assembly and connection technology (housing and wiring / connection of microelectronic and nonelectronic components to form a system). In doing so, processes of thin and thick film technology are used, in the latter the components are applied to a film or embedded and connected, they are only of importance for special applications (high frequency technology).

The production takes place in an extremely clean environment, so-called clean rooms, with a very low density of dust particles. This is necessary because the structures to be manufactured are in the micrometer and nanometer range and even the smallest particles (<0.1 µm) can cause manufacturing defects that result in the failure of a complete circuit. The manufacturing process itself can be divided into three areas (in addition to functional tests): the manufacture of the substrate and the manufacture of the components (transistors, diodes, etc.), the so-called front end, and their "packaging" in housings, the so-called back end .

Substrate production

Integrated circuits are manufactured on so-called wafers (single-crystalline semiconductor wafers), so that several integrated circuits can be manufactured in parallel and costs can be reduced. Hundreds and, in the case of simple structures (for example individual transistors), thousands of identical integrated circuits are produced in parallel on a wafer.

To meet the high requirements for the production of integrated circuits, it is necessary to manufacture the substrate in the form of high-purity single crystals. The vast majority (more than 99%) of the integrated circuits use silicon as the substrate material. Other materials such as gallium arsenide are also used for very high-frequency or optical applications. For special applications, silicon is also used on the insulating substrate sapphire (Silicon on Sapphire, SOS).

In the case of silicon, a single-crystalline cylinder (ingot) is first drawn from a high-purity silicon melt (cf. extraction of pure silicon). The so-called Czochralski process (CZ process) is primarily used for this. An alternative method is zone melting, which can also be used for further cleaning of the CZ ingots; For some special applications, higher levels of purity are required than a foreign atom on 10 ⁹ atoms of the CZ ingots. Depending on the diameter, the ingots are sawn into 0.5-1.5 mm thin wafers. The silicon wafers used today in mass production have diameters of 150, 200 or 300 mm (often also referred to as 6, 8 or 12 inches). Various etching, grinding and polishing processes give you an almost perfect flat surface with unevenness on the order of less than one nanometer, i.e. with surface roughness of just a few atomic layers.

The so-called front-end in the manufacture of integrated circuits deals with the manufacture of electrically active components (transistors, capacitors, etc.), the so-called front-end-of-line (FEOL), and their wiring (metallization), the so-called Back-end-of-line (BEOL). A wide variety of semiconductor technology processes are used to build up layers (epitaxy, sputter deposition, vapor deposition, CVD etc.), layer removal, and structuring (photolithography). Furthermore, methods for changing material properties (for example doping) are used.

Nowadays (2009), after metallization, there is often a random or complete test of the circuits with needle testers in the pane, especially to determine the yield and as feedback on technological parameters. This saves capping the sometimes considerable scrap. For the determination of technological parameters, the test (e.g. layer thickness test) is usually carried out directly after the respective process, here it is sometimes important to also include the respective systems, since systems of identical construction with the same parameters generate deviations that may lie outside the tolerance range.

Back end
See also: “Back-End” in the Integrated Circuit article

In the subsequent manufacturing stage, the back end, the ICs are then separated. This is generally done by sawing (rarely also by scratching and breaking) the wafer into dies (the so-called chips). In the subsequent packaging, the individual ICs are then placed in a housing and contacted, the so-called bonding. Depending on the type, different methods are used, for example chip bonding or wire bonding.

The capping (housing) is used for hermetic sealing against environmental influences - the housing must be gas and light-tight for purely electrical circuits - and for better usability: either the chip together with the bond wires is enclosed in a cavity (sheet metal, ceramic, possibly with a window) or encased in resin. The external connections are implemented, for example, as a Dual in-line package (DIL) or Plastic Leaded Chip Carrier (PLCC). Highly complex circuits (mostly for mobile applications) have recently (2009) also been used without a socket housing and soldered directly to the respective circuit boards (see Ball Grid Array).

At the end there is another function test, in which assured properties are checked on all circuits. The type test is carried out on a sample basis or only in the development phase. The routine test is used for sorting in circuits of different quality classes (for example, according to offset voltage for operational amplifiers). Test results and the type of capping determine the area of application. In this way, high qualities are manufactured for extended operating temperatures and environmental requirements (the so-called MIL standard for military and space applications). Higher tolerances and plastic capping are suitable for mass applications (consumer goods).

In addition to the monolithic circuits, there are also so-called thick-film hybrid circuits. Individual functions of the circuit are implemented in different semiconductor chips and applied to an additional carrier material and wired in a screen printing process. In this way, passive components can be implemented in addition to connecting lines.

If particularly compact components are required, for example in mobile phones, several individual circuits are also electrically connected in the shortest possible way and housed in a common housing, see Multi-Chip module.

Function test

In order to react early to process fluctuations, correct faulty processes if necessary, or even take wafers or lots out of production, the unfinished ICs are tested after many process steps. In the front end, these are mostly random samples. After the front end, all ICs are usually tested for their function before further processing. In some cases, certain functions (high-frequency circuits or later connections of the chip that are not routed to pins) can only be tested on the die. Above all, for cost reasons, it must be prevented that non-functional ICs are further processed in the subsequent manufacturing process.

Finally, the packaged chip is also subjected to a final test before delivery in order to determine defects in the back-end production. It also tests some properties that change due to packaging or that cannot be measured without a housing, such as bonding or certain high-frequency properties. The packaged chip can then go to the PCB assembly.

Although these measurements are carried out fully automatically on special test systems (Automatic Test Equipment), the associated costs for highly integrated processor chips have almost reached the manufacturing costs. Above all, this is due to the fact that only limited scale effects take effect during testing (parallelization is only possible, for example, with purely digital circuits) and newer ICs contain more and more functions that have to be tested one after the other.

Economy

The industry that deals with the manufacture of microelectronic components - the semiconductor industry - shows two properties that distinguish it from others.

Great economies of scale: semiconductor factories for the mass production of components of the smallest possible structure sizes are only profitable from a certain size. Furthermore, these factories are orders of magnitude more expensive than comparable manufacturing facilities in other industries: today (2004) the costs are for the construction and equipment of a high-volume, state-of-the-art factory at approximately $ 2 billion. Both together lead to the so-called pig cycle: There are only a comparatively small number of current semiconductor factories worldwide. If the industry is doing well, which usually means that the supply of semiconductor devices is less than the demand, it will expand its manufacturing capacities because most companies will only be able to raise the sums for the expansion. Every new factory that goes into production increases the global market volume of available modules by percentage points, since they have to be very large for profitability reasons. The sudden increase in available volume leads to a correspondingly sharp drop in the price of the components, which settles again as soon as demand has caught up with the supply again. Due to the drop in prices, many companies are unable to expand their production capacities for a while - it is approaching the next shortage of the offer. Then the cycle repeats.

Attribution of strategic importance: Many states attribute strategic importance to the semiconductor industry. This is mostly due to the "germ cell effect" for other high technologies. In the area of semiconductor industries, not only highly qualified suppliers from the chemical and plant engineering sectors are developing, but also from the customer industries for components, for example the computer and electronics industries. In some cases, the strategic importance is also based on military reasons. For example, the USA considers the importance of microelectronics for armaments programs so important that devices for the production of current ICs as well as the circuit designs and even the circuit development software are the subject of their export control lists. This highly valued significance means that a large number of countries promote the settlement of the semiconductor industry in many ways: from start-up financing, special tax arrangements, state credit guarantees to state-funded research at university and industrial research centers etc. These grants are also occasionally the subject of economic ones Disputes between states and companies - as last happened in 2003. At that time, DRAM manufacturer Hynix was accused of being excessively supported by the South Korean state in its financial crisis. Hynix's competitors then imposed punitive tariffs on imports of its products in the United States, the European Union ^[34] and most recently Japan, against which South Korea protested.

Business models: As in many other industries, there is the full manufacturer - called Integrated Device Manufacturer (IDM). An IDM creates the product design, develops the manufacturing technology, manufactures the component and sells it itself. However, there are also the "Fabless Design Houses" and "Foundries". Fabless design houses create the product design according to the specifications or in cooperation with the foundry, which will produce it later, and sell the finished product. The foundry develops the manufacturing technology, provides its customers with technology-specific tools for chip design (EDA) and manufactures the ICs. Combinations of these business models and niche models can also be found in practice.

Optoelectronics

The term optoelectronics (sometimes also called optronics or optotronics) was created from the combination of optics and semiconductor electronics and broadly includes all products and processes that enable the conversion of electronically generated data and energies into light emission and vice versa.

Background is e.g. B. the attempt to combine the advantages of electronic data processing and processing with the advantages of fast and electromagnetic and electrostatically undisturbed broadband transmission property of light. At the same time, this also includes the conversion of electrical energy into light and vice versa on the basis of electronic semiconductor technology, whereby the generated light can either spread in free space or in solid translucent media (optical fibers such as fiber optic cables) or as in optical storage technology can also be used to store electronically generated data.

The optoelectronics has become an integral part of everyday life because it includes components such as B. includes lasers, screens, computers, optical storage and data carriers.

First and still valid system proposal for optoelectronic message transmission using a laser diode, glass fiber and photodiode by Manfred Börner, 1965 ^[1]

Optoelectronic components are components that act as an interface between electrical and optical components or devices that contain such components. This mostly (but not exclusively) means microelectronic components that function on the basis of semiconductors.

The components of optoelectronics can be divided into actuators (transmitters) and detectors (receivers). Optoelectronic actuators are semiconductor components that generate light from electricity, i.e. laser and light emitting diodes. The emission spectrum can be in the visible as well as in the invisible (UV or infrared) spectral range. Optoelectronic detectors are the reversing components of the actuators, i.e. photoresistor, photodiode (also solar cell) and phototransistor. Light sensors can also be built as an integrated circuit, e.g. B. as a CCD sensor. Photomultipliers are also counted among optoelectronics. If the actuator and detector are operated as a system, this results in an optical sensor, a so-called optosensor. The specialist area is also referred to as optosensor technology. The simple combination of an actuator and detector in one component is called an optocoupler.

In addition to these, there are other components that are required for the transmission, amplification or modulation of signals. Optical signals can be transmitted through free space or in conjunction with waveguides and optical circuits (see integrated optics). Optical modulators are components that impress (modulate) light on a defined characteristic. This can be a temporal or spatial amplitude or phase variation, for example. These include, for example, optical amplifiers, optoelectronic multiplexers and magnetorestrictive optical microreflectors.

semiconductor

Semiconductors are solid bodies whose electrical conductivity is between that of electrical conductors (> 10 ⁴ S / cm) and that of non-conductors (<10 ^-8 S / cm). ^[1] Since the border areas of the three groups overlap, the negative temperature coefficient of the specific resistance is another important characteristic of semiconductors, that is, their conductivity increases with increasing temperature, they are so-called thermistors. The reason for this is the so-called band gap between the valence band and the conduction band. Close to the absolute zero temperature, these are fully or unoccupied and semiconductors are therefore non-conductive. In contrast to metals, there are primarily no free charge carriers. B. arise from thermal excitation. The electrical conductivity of semiconductors rises steeply with temperature, so that they are more or less conductive at room temperature, depending on the material-specific distance between the conduction and valence bands. Furthermore, by introducing foreign atoms (doping) from another main chemical group, the conductivity and the conductivity character (electron and hole conduction) can be influenced in a wide range.

Semiconductors are differentiated into crystalline and amorphous semiconductors based on their crystal structure, see section Classification. Furthermore, they can have different chemical structures. The best known are the element semiconductors silicon and germanium, which are composed of a single element, and compound semiconductors such as, for example, the Ill-V compound semiconductor gallium arsenide. Furthermore, organic semiconductors have gained in importance and popularity in recent decades, for example, they are used in organic light-emitting diodes (OLEDs). However, there are also other substances with semiconductor properties, such as. B. organometallic semiconductors as well as materials that get semiconductor properties through nanostructuring. Ternary hydride compounds such as lithium barium hydride (LiBaH ₃ ) are brand new.

Semiconductors are important for electrical engineering and in particular for electronics, with the possibility of influencing their electrical conductivity by doping playing a decisive role. The combination of differently doped areas, e.g. B. at the p-n transition, enables both electronic components with a direction-dependent conductivity (diode, rectifier) or a switch function (z. B. transistor, thyristor, photodiode), the z. B. can be controlled by applying an electrical voltage or a current (see. Working conditions in metal-insulator-semiconductor structure). Other applications in addition to the transistor are: thermistors, varistors, radiation sensors (photoconductors, photoresistors, photodiodes or solar cells), thermoelectric generators, Peltier elements and radiation or light sources (laser diode, light-emitting diode). The majority of all semiconductor components manufactured are silicon-based. Silicon does not have the very best electrical properties (e.g. charge carrier mobility), but in combination with its chemically stable oxide it has significant advantages in production (see also thermal oxidation of silicon).

history

Stephen Gray discovered the difference between conductor and non-conductor in 1727. After Georg Simon Ohm established Ohm's law in 1821, which describes the proportionality between current and voltage in an electrical conductor, the conductivity of an object could also be determined.

The Nobel Prize winner Ferdinand Braun discovered the rectifier effect of semiconductors in 1874. He wrote: “[...] with a large number of natural and artificial sulfur metals [...] the resistance of these was different with direction, intensity and duration of the current. The differences amount to up to 30 percent of the total value. ”This is the first time that he has described that resistance can vary.

Greenleaf Whittier Pickard received the first patent in 1906 for a silicon-based tip diode for demodulating the carrier signal in a detector receiver. ^{[2] [3]} Initially, mostly galena used in the same receiver ( "Pickard Crystal Radio Kit") as a semiconductor, in the 1920s, more robust and more powerful diodes based on copper sulphide contacts emerged. The functionality of the rectifier effect based on a semiconductor-metal transition remained unclear for decades despite its technical application. It was only in 1939 that Walter Schottky was able to lay the theoretical foundations for describing the Schottky diode named after him.

The first patent on the principle of the transistor was registered in 1925 by Julius Edgar Lilienfeld (US physicist of Austrian-Hungarian origin). ^[4] Lilienfeld described an electronic component in his work, which in the broadest sense is comparable to today's field effect transistors. At the time, he lacked the necessary technologies to implement field effect transistors in practice. ^[5]

When scientists at Bell Laboratories in 1947, John Bardeen, William Bradford Shockley and Walter Houser Brattain put two metal wire tips on a germanium plate and were thus able to control the p-type zone with the second wire tip with an electrical voltage, they realized the tip transistor (bipolar transistor) . This earned them the 1956 Nobel Prize in Physics and the foundation of microelectronics.

Eberhard Spenke and his team at Siemens & Halske AG succeeded in producing high-purity silicon in 1954 using the zone melting process. In the mid-1950s, this, together with the availability of an insulating material (silicon dioxide) with favorable properties (not water-soluble like germanium oxide, easy to manufacture, etc.) brought about the breakthrough of silicon as a semiconductor material for the electronics industry and about 30 years later for the first products in microsystem technology . For the production of integrated circuits, silicon (2009) is used almost exclusively today (2009) using the Czochralski process.

Alan Heeger, Alan MacDiarmid and Hideki Shirakawa showed in 1976 that when doping polyacetylene - a polymer that is an insulator in the undoped state - with oxidizing agents, the specific electrical resistance down to 10 ^-5 Ω · m (silver: = 10 ^-8 Ω · m) can decrease. In 2000 they received the Nobel Prize in Chemistry (see section on organic semiconductors). ^{[6] [7]} Classification Element semiconductors Chemical classification of compound semiconductors (without org. HL) Organic semiconductors Ge, Si, α-Sn, C (fullerenes), B, Se, Te III-V: GaP, GaAs, InP, InSb, InAs, GaSb, GaN, Tetracen, Pentacen, Phthalocyanine, Polythiophene, PTCDA, MePTCDI, Quinacridon, Acridon, Indanthron, Flavanthron, Perinon, Alq3 AIN, InN, AlxGa _1-x As, In _x Ga _1-x N II-VI: ZnO, ZnS, ZnSe, ZnTe, Mixing systems: Under pressure: Bi, Ca, Sr, Ba, Yb, P, S, I CdS, CdSe, CdTe, Polyvinyl carbazole, Hg (1-x) Cd (x) Te, BeSe, BeTe, HgS TCNQ complexes III-VI: GaS, GaSe, GaTe, InS, InSe, InTe ... I-III-VI: CuInSe ₂ , CuInGaSe ₂ , CuInS ₂ , CuInGaS ₂ ... IV-IV: SiC, SiGe IV-VI: SnTe

The classic, i.e. crystalline electronic, semiconductors used in microelectronics can be classified into two groups, the element semiconductors and the compound semiconductors. The element semiconductors include elements with four valence electrons, for example silicon (Si) and germanium (Ge). The group of compound semiconductors includes chemical compounds that have an average of four valence electrons. These include connections of elements of III. with the 5th main group of the periodic table (III-V compound semiconductor), such as gallium arsenide (GaAs) or indium antimonide (InSb), and the 2nd secondary with the VI. Main group (Il-VI semiconductors), such as zinc selenide (ZnSe) or cadmium sulfide (CdS).

In addition to these frequently used semiconductors, there are also the I-Vll semiconductors, such as copper (I) chloride. Even materials that do not have four valence electrons on average can be referred to as semiconductors if they have a specific resistance in the range of greater than 10 ^-4 Q · m and less than 10 ⁶ Ω · m.

Organic semiconductors are another large class. They are called organic because they are mainly made up of carbon atoms. They are divided into semiconducting polymers (chains of different lengths from individual monomers and small molecules (single, closed units). Although fullerenes, carbon nanotubes and their derivatives are strictly small molecules, they are often perceived as a separate subgroup. Classic examples of organic semiconductors are P3HT (poly-3-hexylthiophene, polymer), pentacene (small molecule) or PCBM (phenyl-C61-butyric acid methyl ester, fullerene derivative). Organic semiconductors are used in light-emitting diodes (OLEDs), solar cells (OPVs) and field effect transistors .

• Kristalline Halbleiter
• Physikalische Grundlagen
• Diamantstruktur (Elementarzelle)
• Zinkblendestruktur (Elementarzelle)

Several semiconducting molecules or atoms form a crystal together or create a disordered (amorphous) solid. Roughly, most inorganic semiconductors can be classified as crystalline, most organic semiconductors as amorphous. However, whether a crystal or an amorphous solid is actually formed essentially depends on the manufacturing process. For example, silicon can be crystalline (c-Si) or amorphous (a-Si), or can also form a polycrystalline mixed form (poly-Si). There are also single crystals of organic molecules.

• Crystalline semiconductors
• Physical basics
• Diamond structure (unit cell)
• Zinc blend structure (unit cell)

The semiconductor properties of substances go back to their chemical bonds and thus their atomic structure. Semiconductors can crystallize in different structures, such as silicon and germanium crystallize in the diamond structure (purely covalent bond), III-V and II-VI compound semiconductors, however, mostly in the zinc blende structure (mixed covalent-ionic bond).

Typical ribbon model of metals, semiconductors and insulators (E = energy - can be equated with work W; x = spatial expansion in one-dimensional direction); E _F represents the position of the Fermi energy at T = 0 K.

The basic properties of crystalline semiconductors can be explained on the basis of the ribbon model: the electrons in solids interact with each other across a large number of atomic distances. In fact, this leads to an expansion of the possible energy values (still available as discrete levels in the individual atom) to extended energy areas, the so-called energy bands. Since the energy bands are different from each other depending on the expansion and type of atom, bands can overlap or be separated by energy areas in which no permitted states exist according to quantum mechanics (energy or band gap).

In semiconductors, the highest occupied energy band (valence band) and the next higher band (conduction band) are now separated by a band gap. The Fermi level lies exactly in the band gap. ^[8] At a temperature near absolute zero, the valence band is fully occupied and the conduction band is completely free of charge carriers. Since unoccupied tapes do not conduct electrical current due to the lack of mobile charge carriers and charge carriers in fully occupied tapes cannot absorb energy due to the lack of accessible free states, which leads to limited mobility, semiconductors do not conduct the electrical current at a temperature close to absolute zero.

Partially occupied tapes are necessary for the conduction process, which can be found in metals by overlapping the outer tapes at any temperature. As mentioned above, this is not the case with semiconductors and insulators. In contrast to insulators (E _G > 4 eV ^[9] ), the band gap (called "forbidden band" or "forbidden zone") in semiconductors is relatively small (InAs: = 0.4 eV, Ge: ≈ 0.7 eV) ,

Si: ≈ 1.1 eV, GaAs: = 1.4 eV, SiC: ≈ 2.39 ... 3.33 eV, diamond: ≈ 5.45 eV), so that, for example, by the energy of the thermal vibrations at room temperature or Many electrons can be excited from the fully occupied valence band into the conduction band by absorption of light. Semiconductors therefore have an intrinsic electrical conductivity that increases with temperature. That is why semiconductors are also classified as thermistors. The transition from semiconductors to insulators is fluid. For example, gallium nitride (GaN; use in blue LEDs) with a band gap energy of ≈ 3.2 eV is also counted among the semiconductors, but diamond with a band gap of = 5.5 eV is no longer counted. Semiconductors with a band gap significantly larger than 1 eV are also referred to as semiconductors with a wide band gap (English wide-band gap semiconductor).

If, as described above, an electron in a semiconductor is excited from the valence band into the conduction band, it leaves a defect electron in its original position, called a “hole”. Bound valence electrons in the vicinity of such holes can “jump” into a hole due to a change of location, which causes the hole to migrate. It can therefore be seen as a moving positive charge. Both the excited electrons and the defect electrons thus contribute to the electrical conduction.

Electrons from the conduction band can recombine with the defect electrons (electron-hole recombination). This transition between the levels involved can take place by emitting electromagnetic recombination radiation (photon) and / or by emitting a pulse to the crystal lattice (phonon).

Direct and indirect semiconductors

Semiconductors are divided into two groups, the direct and the indirect semiconductors. Their different properties can only be understood by considering the band structure in the so-called impulse space: The charge carriers in the semiconductor can be understood as material waves with a quasi-impulse. Within a band, the energy depends on the quasi-pulse (often given as a wave vector).

The extreme values of the energy within the bands, i.e. the band edges, lie with different wave vectors - where exactly depends on the material and the structure. When an electron is excited from the valence band into the conduction band, it is energetically most favorable (and therefore most likely) if it is excited from the maximum of the valence band to the minimum of the conduction band.

If these extremes are almost at the same quasi-pulse, excitation by a photon, for example, is easily possible since the electron only has to change its energy, but not its pulse. One speaks of a direct semiconductor. However, if the extremes are at different quasi-pulses, the electron must change its pulse in addition to its energy in order to be excited into the conduction band. This impulse cannot come from a photon (which has a very small impulse), but has to be contributed by a lattice oscillation (also called a phonon).

In principle, the same applies to the recombination of electron-hole pairs. In a direct semiconductor, a light quantum can be emitted during recombination. In the case of an indirect semiconductor, on the other hand, a phonon for the pulse would have to be generated (or absorbed) for the photon for the energy and the radiative recombination becomes less likely. Other non-radiative recombination mechanisms then often dominate, e.g. B. about impurities. It follows that only direct semiconductors can be used for effective radiation generation. Direct and indirect semiconductors are distinguished from one another by means of an absorption test. As a rule, element semiconductors (silicon, germanium) and Compound semiconductors from the IV. Main group indirect and compound semiconductors from different main groups (III / V: GaAs, InP, GaN) directly.

In the case of a band structure in which different points in the impulse space are possible near the line or valence band edge, the so-called Gunn effect can occur.

Semiconductors and impurity semiconductors

The density of free electrons and holes in pure, i.e. undoped, semiconductors is called intrinsic charge carrier density or intrinsic conduction density - an intrinsic semiconductor is therefore also called intrinsic semiconductor, the dominant conduction mechanism is intrinsic conduction. The charge carrier density in the undoped semiconductor is strongly dependent on the temperature and increases with it. If, on the other hand, the concentration of the charge carriers in the conduction band (electrons) or in the valence band (holes) is determined by the dopant, one speaks of an impurity semiconductor or extrinsic semiconductor - the dominant conduction mechanism here is the impurity conduction.

Doping and impurity line

Donors and acceptors Degree of doping of silicon Strength n-conductive p-conductive Normal doping a donor on 10 ⁷ an acceptor on 10 ⁶ Strong funding a donor on 10 ⁴ an acceptor on 10 ⁴

The electrical properties of the (pure) semiconductor can be influenced by introducing impurities into a semiconductor crystal. Impurities are foreign atoms which differ, for example, in their valency from the atoms of the host material, examples are boron or phosphorus in a silicon crystal. The process is generally referred to as doping or “doping”. In addition, different components, e.g. B. a bipolar transistor. In some semiconductors, even the smallest amounts of foreign atoms (e.g. one foreign atom per 10 million semiconductor atoms) can lead to extreme changes in the electrical properties that far exceed intrinsic semiconducting.

The introduction of impurities creates additional, locally bound energy levels in the band diagram of the crystal. The levels generally lie in the energy gap (band gap) between the valence band and the conduction band, which otherwise exists for the host material. Due to the smaller energy differences of the “intermediate levels” to the valence or conduction band compared to undoped semiconductors, these levels can be excited more easily and thus make mobile charge carriers available. The chemical potential shifts from the middle of the band gap to the vicinity of the additional levels. There are therefore more charge carriers available for the conduction of the electrical current, which manifests itself in an increased conductivity compared to the pure semiconductor. This line mechanism is therefore also called fault line. A distinction is made between two types of defects: donors and acceptors.

Foreign atoms that have one electron more in the valence band than pure semiconductors are referred to as (electron) donors (lat. Donare = give). Such areas are also referred to as n-doped semiconductors. If such foreign atoms are introduced into the semiconductor (substituted), each of these foreign atoms (in the case of silicon doped with phosphorus) brings an electron with it which is not required for the bond and can be easily detached. An impurity level is formed near the lower energy of the conduction band.

Analogously, (electron) acceptors (lat. Accipere = accept) are foreign atoms that have one electron less in the valence band. This electron is missing for the bond to the neighboring atom. They act as an additional defect electron (hole) with (p-doping), which can easily be occupied by valence band electrons - that is why the term hole donors is used in some considerations. In the band diagram, such an impurity level is close above the valence band edge.

In an intrinsic semiconductor, the charge carrier concentrations of electrons and holes are the same (electron-hole pairs). Therefore, both types of charge are approximately equally divided Charge transport involved. This balance can be influenced in a targeted manner by introducing donors and acceptors.

When doping with donors, mainly the electrons in the conduction band, when doping with acceptors, the imaginary, positively charged holes in the valence band ensure electrical conductivity. In the first case one speaks of electron line or n-line (n → negative), in the other case of hole line or p-line (p → positive). Semiconductor areas with an excess of electrons are referred to as n-doped (as mentioned above), those with a deficiency, ie with “hole excess”, as p-doped. In the n-conductor, the electrons are called majority charge carriers (the majority of charge carriers are present), the holes as minority charge carriers, in the p-conductor the corresponding reversal applies. By cleverly combining n- and p-doped regions (see p-n junction) one can build individual, so-called discrete semiconductor components such as diodes and transistors and complex integrated circuits made up of many components in a single crystal. The intrinsic semiconducting is often even disturbing in these electronic components (see e.g. leakage current), so that they sometimes have to be cooled explicitly.

Conduction mechanisms in doped semiconductors

Conduction mechanisms in doped and undoped semiconductors depending on the temperature

At absolute zero (T = 0 K), doped and undoped semiconductors do not differ in terms of charge carrier density - there is not enough energy available to excite electrons in the conduction band or at impurity levels. If the temperature is increased (the available energy increases due to thermal excitation), the conditions change. Since the energetic distances of the impurities to the valence or conduction band are very much smaller than the band spacing, electrons can be excited from the donor level to the conduction band or holes from the acceptor level to the valence band. Depending on the temperature, free charge carriers are available, and the conductivity of doped semiconductors increases. Since not all impurity levels are ionized or occupied, this area is known as the impurity reserve. If the temperature is increased further until all impurity levels are ionized or occupied, one speaks of impurity exhaustion. The charge carrier density and thus the conductivity in this area essentially depends only on the doping concentration. Because of the decreasing mobility with increasing temperature, in this temperature range similar to metals i. A. a conductivity that decreases slightly with temperature. If the temperature is increased still further, enough energy is then available to lift electrons directly from the valence band into the conduction band. Since typical doping concentrations are significantly lower than the number of semiconductor atoms (at least six orders of magnitude), the charge carrier generation of electron-hole pairs predominates; this area is referred to as intrinsic or intrinsic conductivity of the semiconductor.

Interfaces

The combination of a p-doped and an n-doped semiconductor creates a p-n junction at the interface. The combination of a doped semiconductor with a metal (e.g. Schottky diode) or a non-conductor is also of interest, and when two semiconductors, for example gallium arsenide and aluminum gallium arsenide, lie one above the other, a heterojunction occurs. Not only p-n junctions are important, but also p-p junctions and n-n junctions, the so-called isotypic heterojunctions, which are used, for example, in a quantum well.

Recently, efforts have been made to combine semiconductors, superconductors and silicon and III-V semiconductors on one chip. Since the crystal structures are not compatible, fractures and lattice defects occur in the interface if it is not possible to find suitable materials for an intermediate layer that is only a few atomic layers thick and in which the lattice distances can be equal. ^[10]

Semimagnetic semiconductors

Semimagnetic semiconductors belong to the group of compound semiconductors. These are compounds such as indium antimonide (InSb), which are doped with a few percent manganese (Mn) and show semimagnetic properties at room temperature. ^[11] Indium arsenide (InAs) and gallium arsenide (GaAs) also show semi-magnetic properties when heavily doped with manganese and then referred to as InMnAs or GaMnAs. The Curie temperature is 50-100 K for InMnAs and 100-200 K for GaMnAs and thus clearly below room temperature. ^[12] A characteristic property this semi-magnetic semiconductor is the big Zeeman effect. In English, semimagnetic semiconductors are called diluted magnetic semiconductors because they are magnetically thinned.

Amorphous semiconductors

Amorphous semiconductors have no crystal structure. An example of the technical application is amorphous silicon in photovoltaics. Due to their high impurity density, they have to be processed differently than crystalline semiconductors, e.g. B. to make doping possible.

Organic semiconductors

Generally, organic materials are electrically insulating. If molecules or polymers have a conjugated bond system consisting of double bonds, triple bonds and aromatic rings, these can also become electrically conductive and be used as organic semiconductors. This was first observed in 1976 with polyacetylene. ^[13] Polyacetylene is an unbranched polymer with an alternating double bond and single bond (-C = CC = C-). Is this plastic still an acceptor such. B. chlorine, bromine or iodine added (oxidative doping), there are additional holes. By adding a donor such as e.g. B. Sodium (reductive doping) the plastic receives additional electrons. As a result of this chemical change, the double bonds break and a continuous conduction band is created: the originally non-conductive polymer becomes electrically conductive. If molecules or polymers have semiconducting properties even in the undoped state, one speaks, as with inorganic semiconductors, of intrinsic conductivity (intrinsic conductivity), e.g. B. pentacene or poly (3-hexylthiophene). If the plastic is produced in the form of a thin layer from 5 to 1000 nm thick, it is ordered enough to form an electrically continuous layer.

Areas of application

microprocessor
→ Main article: semiconductor technology and semiconductor electronics

Semiconductors are used in various forms in electronics. The associated sub-area is referred to as semiconductor electronics. These primarily include the semiconductor-based integrated circuits (ICs, such as microprocessors, microcontrollers, etc.) and various components in power electronics (e.g. IGBTs). Companies in this sector are also known as semiconductor manufacturers. Other areas of application with increasing importance are photovoltaics (solar cells) as well as detectors and radiation sources in optics and optoelectronics (for example photodetectors and light emitting diodes). The department that deals with the manufacture of semiconductor-based microelectronic components and assemblies is known as semiconductor technology. Prerequisite is knowledge of how the semiconductor must be processed in order to achieve the desired electrical behavior. This includes doping the semiconductor and designing the interface between the semiconductor and another material.

economy

The polysilicon market is currently (2010) in transition. After demand for polysilicon was high due to the high demand from the solar market in 2008/2009, the price rose sharply. This has prompted a number of companies to start building new production facilities. The established manufacturers also expanded their capacities. In addition, new providers - especially from Asia - are entering the market. Which of these manufacturers will be able to put their systems into operation as announced and still operate profitably when prices have fallen sharply is uncertain. ^{[14] [15]}

The world's largest manufacturer of wafers, including compound semiconductors, is the Japanese company Shin-Etsu Handotai (SEH) with wafer sales of $ 4 billion in 2007. The world's second largest, also Japanese, manufacturer Sumitomo Mitsubishi Silicon Corp. (Sumco) had sales of $ 2.7 billion in the same year. This is followed by the German Siltronic AG (Wacker) with $ 1.8 billion and the American company MEMC Electronic Materials with $ 1.2 billion. These four companies share approximately 79% of the total $ 12.5 billion Si wafer market. ^[16]

During the global financial crisis, sales almost halved, and in 2009 only silicon was sold for $ 6.7 billion. Already in 2010 sales had recovered to $ 9.7 billion. ^[17]

Electronic paper

Electronic paper (e-paper for short, also called e-paper, e-paper or e-paper) is the term used to describe display techniques that try to reproduce the appearance of ink or color on paper.

E-paper displays reflect light like normal paper, so they are passive (non-luminous) displays. Based on the English usage, such screens are also referred to as reflective displays. With some display technologies, texts or images are displayed permanently without the need for a maintenance voltage. However, the display can be changed later. Electronic paper is flexible for some manufacturers - similar to normal paper.

Although there are various processes for producing electronic paper and a large number of companies are now researching and developing them ^[1] , the term e-ink is often used as a synonym for electronic paper in common usage. Strictly speaking, E Ink (own spelling without hyphen) is only the brand name of the E Ink Corporation product that is currently used in most modern e-book readers and is based on the appearance of electrophoresis.

technology

In the 1970s, researcher Nick Sheridon at Xerox's Palo Alto Research Center was the first to develop electronic paper. It was called Gyricon and consisted of small, statically charged balls. These were two-tone: black on one side and white on the other. The text content of the paper could be changed by an applied electric field. This rotated the beads up or down so that either the black or white side was visible.

However, Gyricon could not be produced cheaply, so Xerox dissolved the company Gyricon LCC, which was founded for marketing at the end of 2005.

Electrophoresis

In the 1990s, a team ^[2] led by Joseph Jacobson ^[3] at MIT used small microcapsules in which electrically charged white particles floated in colored oil. Due to the polarity of an applied electric field, the white particles migrate to the top of the microcapsule (i.e. visible to the viewer), or to the bottom, so that the viewer saw the darker color of the oil at this point. The American company E Ink Corporation developed its current electronic paper based on this technology based on electrophoresis.

This electronic paper contains microcapsules with an average diameter of approx. 40 µm, which contain positively charged white particles and negatively charged black particles in a transparent viscous polymer. The display is changed by briefly applying an electrical voltage and then remains stable for several weeks. The shape and diameter of the microcapsules are irregular, but this is insignificant, since each individual pixel is made up of many microcapsules, and these irregularities are averaged out.

Macro shot of an e-ink screen. The microcapsules are visible in the enlarged view.

The use of microcapsules also allows flexible plastic to be used as the carrier material instead of glass.

In the case of segment displays, the pixels are controlled by means of passive transparent electrodes and in the case of matrix displays by means of a TFT active matrix, as is also used in the case of LC screens.

The display of gray levels is controlled by the time course of the applied voltage. Originally, eight gray levels could be shown, the current displays work with 16 gray levels. In conjunction with raster processes known from printing technology and image processing, an apparently stepless gray value display is achieved.

Colored displays are either based on black and white electronic paper with upstream color filters, or they are equipped with colored pigments.

E Ink Corporation has presented various applications since 1999 and in 2004 became the first manufacturer to start mass production of electronic paper. ^[4] other manufacturers' products were or are, for example, "SiPix Microcup®" the American company Sipix (which has been taken over by the E Ink Corporation in 2012), the flexible electronic paper "Lectum" the manufacturer "Plastic Logic", which in Dresden is produced, ^[5] the flexible e-ink displays from LG Display ^[6] or the "O-paper" from the Chinese manufacturer Guangzhou OED Technologies. ^[7] Another manufacturer of electrophoretic electronic paper with its own technology was Bridgestone, ^[8] whose development was stopped in 2012. ^[9]

Since 2002 ^[10] , companies such as E-Ink, Bridgestone or Philips have presented various prototypes of colored electrophoretic e-paper ^{[11] [12] [13]} , but none of them have gone into series production. E Ink Corporation started producing color filters “Triton” electronic paper in 2011, and in 2016 launched “ACeP”, which uses colored pigments. ^[14]

Flexible electronic paper is mainly used in industrial displays and in advertising. With electronic readers, which are preferably designed for the best possible contrast and a long service life, glass displays dominate, even if prototypes with flexible screens are occasionally shown, such as the foldable e-ink display. ^[15]

Electrophoretically controlled total reflection

At SID Display Week 2017, the US company CLEARInk presented displays that are based on the combination of a film with totally reflecting lenses and a layer of electrically charged particles behind them in a liquid. The particles are moved by an applied electric field, and when they adhere to the back surface of the lens, the total reflection is suppressed by absorption.

This technology can be used to manufacture displays that are fast enough for video playback, and bistable displays should be possible that reflect significantly more light than is possible with e-ink displays. ^{[16] [17] [18] [19]}

Bistable LCD

Some companies produce electronic paper based on bistable LCDs. These enable a neutral white with high albedo (surface reflection) and resolutions up to 200 dpi. One example is the Cholesteric Liquid Crystal Display. Prototype high resolution electronic paper. The content written on the display is retained for weeks even without a voltage source (bistable state).

Electrowetting

The Philips company offshoot Liquavista has developed a display technology in which a colored oil and water layer lie on top of each other. The light transmittance of the individual pixels is influenced by changing the surface tension by means of an applied electrical voltage (electrical wetting). This enables colored and fast reflective displays with high contrast and low energy consumption to be produced, the switching speed of which also enables video playback. ^[20]

The functional prototype of an e-book reader with a colored 6 "electrowetting display was presented at CES 2010. ^[21]

Liquavista was taken over by Samsung in early 2011, ^[22] and by Amazon in early 2013. ^[23]

Liquavista was closed in 2018. ^[24] A new company called Etulipa tries to establish the technology for billboards. ^[25]

Micromechanically controlled interference modulation
→ Main article: Interferometric modulator display

The mobile radio technology manufacturer Qualcomm produced IMOD displays sold under the name "Mirasol". These were based on the fact that the distance between two reflecting layers was changed micromechanically and thus the light reflection was controlled by means of constructive and destructive interference. The display elements are (as with E-Ink) bistable and enable the production of energy-saving reflective displays. Qualcomm presented functional prototypes of 5.7 "readers with colored Mirasol displays at CES 2010, which are also suitable for video playback. ^{[26] [27]} The start of production on a larger scale was originally announced for 2012, there were but only a few products. ^[28] Afterwards, work was carried out on a new generation of Mirasol displays with the designation SMI (Single Mirror IMOD), in which the individual pixels can be tuned across the spectrum, so that color filters are no longer required. ^{[29 ]} This technique also has no application in end products.

Advantages and disadvantages compared to conventional screens and paper

The Sony Portable Reading System PRS-505 (2007)

• • Der Bildinhalt sieht wegen des geringen Abstandes der bildgebenden Elemente zur Oberfläche aus jedem Blickwinkel gleich aus (Vorteil gegenüber LCDs).
• • Es gibt durch die statische Anzeige kein Flimmern (Vorteil gegenüber Röhrenmonitoren).
• • Es ist sehr dünn und leicht und bei entsprechendem Design auch biegsam.
• • Es ist in allen Größen und Formen herzustellen - vom kleinen Display mit der aktuellen Wetteranzeige bis hin zur großen Anzeigetafel oder Plakatfläche^[30].
• • Es verwendet sehr wenig Energie, um die Anzeige zu erzeugen und aufrechtzuerhalten, da nur zum Ändern des Bildinhaltes (Seitenwechsel) ein Stromfluss erforderlich ist.
• • Es ist sowohl bei normalem Raumlicht als auch in hellem Sonnenschein lesbar, da die bildgebenden Elemente reflektiv sind.

Electronic paper combines the advantages of a computer screen and paper. Compared to conventional screens, such as those used for TV and graphics playback, it offers the following advantages at the current state of development:

• • The image content looks the same from any angle due to the small distance between the imaging elements and the surface (advantage over LCDs).
• • There is no flickering due to the static display (advantage over tube monitors).
• • It is very thin and light and, with the appropriate design, also flexible.
• • It can be produced in all sizes and shapes - from the small display with the current weather display to the large display board or billboard ^[30] .
• • It uses very little energy to generate and maintain the display, since a current flow is only required to change the image content (page change).
• • It can be read in normal room light as well as in bright sunshine because the imaging elements are reflective.

The disadvantages compared to print media such as paper are the rather smooth surface of the display cover, which reflects interference and stray light. Both the gray value resolution (currently only 16 grayscale) and the contrast are still low, and white areas at best achieve a light light gray. The long switching times of the first generation of electronic paper only allow a static display. The color space of the colored displays is comparatively limited. Ghosting effects can also occur due to the energy saving mechanisms of the e-book readers.

Applications

Electronic price tag in the supermarket

As the first field trial to deliver a newspaper, the Belgian business newspaper De Tijd conducted a test with two hundred readers from April to June 2006. The device used was the iLiad from iRex. ^[31]

A field trial with electronic paper as advertising space was carried out by Hitachi at the end of 2006 ^[32] . In local trains on a Tokyo railway line, displays based on electronic paper from Bridgestone were installed as a replacement for ordinary advertising posters. Opinion polls should then decide on marketability.

• • Von zahlreichen Herstellern werden Lesegeräte für elektronische Bücher hergestellt bzw. als OEM-Geräte mit eigener Firmware vertrieben. Dies ist im Augenblick der Haupteinsatz elektronischen Papiers.
• • Als erstes Mobiltelefon hatte das von Motorola hergestellte Motofone F3 für die Anzeige elektronisches Papier eingebaut. Motorola bezeichnete dieses Display als „EPD“, es handelt sich um eine Segmentanzeige mit elektronischem Papier von E Ink. Der dabei im Vergleich zu anderen Anzeigeverfahren ungewohnte Effekt ist, dass die Anzeige bei Entfernen des Akkus aus dem Mobiltelefon erhalten bleibt. Ein Vorteil gegenüber anderen Telefondisplays ist, dass die Darstellung selbst bei direkter Sonneneinstrahlung ablesbar bleibt.
• • Lexar hat die USB-Sticks „JumpDrive Secure II Plus“, „Echo MX“ und „M10“ hergestellt, die den Füllstand ihres Speichers über ein Display mit elektronischem Papier anzeigen. Da der Anzeigeinhalt ohne Stromzufuhr erhalten bleibt, kommen diese Geräte ohne Batterie aus.
• • Western Digital verkauft seit August 2009 externe Festplatten (Serien My Book Elite und My Book Studio), die an ihrer Vorderseite über ein sogenanntes E-Iabel verfügen. Das E-Iabel zeigt eine frei wählbare Textzeile (Inhalt der Festplatte), den verfügbaren freien Speicher und die Aktivierung der Laufwerksverschlüsselung an.
• • Die Firma Seiko brachte 2005 mit dem Modell „Seiko Spectrum“ die erste Armbanduhr heraus, die mit einer E-Ink-Segmentanzeige ausgestattet ist.^[33] 2010 erschien die erste E-Ink-Uhr mit Matrixdisplay. Das Display weist 80.000 Pixel mit einer Auflösung von 300 ppi auf. Jedes Pixel kann eine von vier Graustufenschattierungen anzeigen.^[34]
• • Die österreichische Warenhauskette Billa verwendet E-Ink-Displays als Preisschilder, dadurch können die Verkaufspreise bestimmter Waren vom Büro aus geändert werden.^[35]

There are now many devices in which e-paper displays are used:

• • Numerous manufacturers manufacture reading devices for electronic books or sell them as OEM devices with their own firmware. This is the main use of electronic paper at the moment.
• • The Motofone F3, manufactured by Motorola, was the first mobile phone to incorporate electronic paper. Motorola called this display "EPD", it is a segment display with electronic paper from E Ink. The unusual effect compared to other display methods is that the display is retained when the battery is removed from the mobile phone. A The advantage over other telephone displays is that the display remains legible even in direct sunlight.
• • Lexar has produced the "JumpDrive Secure II Plus", "Echo MX" and "M10" USB sticks, which show the level of their memory on a display with electronic paper. Since the display content is maintained without power supply, these devices do not need a battery.
• • Western Digital has been selling external hard drives (My Book Elite and My Book Studio series) since August 2009, which have a so-called e-label on the front. The E-Iabel shows a freely selectable text line (content of the hard disk), the available free space and the activation of the drive encryption.
• • In 2005, the Seiko company launched the “Seiko Spectrum” model, the first wristwatch to be equipped with an e-ink segment display. ^{[33] In} 2010 the first e-ink watch with a matrix display was released. The display has 80,000 pixels with a resolution of 300 ppi. Each pixel can display one of four shades of gray. ^[34]
• • The Austrian department store chain Billa uses e-ink displays as price tags, which means that the sales prices of certain goods can be changed from the office. ^[35]

Other uses

• • Esquire magazine appeared on September 8, 2008 on the 75th anniversary as the first magazine with a cover that was equipped with electronic paper. However, the e-ink insert used was not a matrix display, but was used to switch headlines on and off, to invert them and to make text areas flash. ^[36] The "Special Collector's Edition" was made 100,000 times.
• • E-paper displays are also increasingly being used for door signs, e.g. B. used in conference rooms with frequently changing use or in supermarkets to mark the prices on the shelves. The screen technology used in e-readers like the Amazon Kindle was conceived by undergraduates at MIT. In: Science Friday. May 10, 2016, accessed September 2, 2017.

Printed electronics

Printed electronics means electronic components, assemblies and applications that are manufactured entirely or partially using printing processes. Instead of printing inks, electronic functional materials that are in liquid or pasty form are printed. Often these are organic materials, so printed electronics is a sub-area of organic electronics and is regarded as a key technology for its production. A considerable reduction in manufacturing costs, the possibility of printing large-area and flexible substrates, and new functionalities are intended to open up fields of application for electronics that were previously not or only partially accessible to conventional (inorganic) electronics. New developments due to the printed electronics stand out. a. in applications such as RFID, displays and solar cells.

Basics

Printed electronics combine knowledge and developments in printing technology, electronics, chemistry and materials science, especially organic and polymer chemistry. Pioneering is the development of organic electronics, which in turn is based on the development of organic electronic functional materials. In addition to the electronic functionalities (conductors, semiconductors, electroluminescence, etc.), processability in liquid form as a solution, dispersion or suspension of such materials led to the development of printed electronics. ^In addition, inorganic materials that can be processed in liquid form are also used.

Insofar as printed electronics are components from organic electronics, they differ in structure, functionality and functionality from conventional electronics. ^[2] Therefore, in consideration of the special manufacturing process, the design and optimization of devices and circuits plays an important role in the development of printed electronics. ^[3]

Almost all industrial printing processes, mostly in adapted or modified form, are used to manufacture printed electronics. Analogous to conventional image printing, in which several layers of color are applied on top of one another, electronic electronics become electronic Thin-film components produced by printing several functional layers on top of each other. However, both the materials used and the required properties of the printed layers differ significantly from one another, ^[4] so that the coordinated adaptation and further development of the printing processes used and the printed materials represent the central task in the development of printed electronics.

For example, the maximum resolution of the printed structures in conventional image printing is determined by the resolution of the human eye. Structure sizes below about 20 µm cannot be perceived by the human eye and usually cannot be produced in conventional printing processes. ^[5] In contrast, are desirable in the electronics higher resolutions, but since they directly affect the integration density, the functionality of components (in particular of transistors). The same applies to the accuracy of fit of layers printed on top of each other.

Fluctuations in the thickness and other layer properties as well as the appearance of holes are only relevant in conventional printing insofar as they can be perceived by the human eye. In contrast, they represent essential quality features for the function of the printed components in printed electronics. Conversely, the visual impression is irrelevant here. In addition, a greater variety of materials have to be processed in printed electronics, which results in new requirements for the compatibility of layers printed on one another with regard to wetting, adhesion and mutual dissolution. ^[6]

Compared to conventional microelectronics, printed electronics are characterized by simpler, more flexible and, above all, less expensive production. It is intended to enable electronic applications to be distributed, networked and penetrated much more widely in everyday life. Is ^[7] An example of this equipment package for everyday goods with printed RFID systems that enables contactless identification in trade and transport. In addition, the printed electronics enable the simple implementation and integration of special properties and functionalities (e.g. flexible displays and solar cells).

Printed and conventional electronics as complementary technologies.

As a rule, the performance of printed electronics with regard to the respective function remains, with a few exceptions e.g. B. in the field of light emitting diodes, behind that of conventional electronics. ^[4] Electronic applications with high switching frequencies and high integration density (so-called "high-end electronics") will be dominated by conventional electronics for the foreseeable future, which, however, also requires comparatively high investment and manufacturing costs. In contrast, printed electronics, as a complementary technology, aims to establish low-cost electronics for areas of application in which the high performance of conventional electronics is not required.

Procedure

The attractiveness of the use of printing processes for the production of electronics results primarily from the possibility of producing stacks of microstructured layers (and thus thin-film components) in a much simpler and cheaper way than in conventional electronics. ^{[8] In} addition, the possibility of generating new or improved functionalities (e.g. mechanical flexibility) also plays a role. The selection of the printing process used depends on the requirements for the printed layers, on the properties of the printed materials and on economic and technical considerations with regard to the products manufactured. The conventional industrial printing processes mainly use inkjet and screen printing as well as the so-called mass printing processes gravure, offset and flexo printing in printed electronics. ^[5] While mass printing processes are mostly used as roll-to-roll processes (web-fed), screen and inkjet printing are mostly used as sheet-fed processes. But there are also other variants.

Bulk printing process

The mass printing processes gravure, offset and flexographic printing are characterized in comparison to other printing processes above all by a far superior productivity, which is expressed in an area throughput of many 10,000 m ² / h. They are therefore particularly suitable for drastically reducing manufacturing costs when applied to the printing of electronics. ^[8] Because of their high level of development and the variety of available processes and process variants, they make it possible At the same time, high resolutions up to 20 µm and below, high layer quality and a wide range of layer properties and processable materials. ^[5] In the field of printed electronics, as with other printing processes, there are significant developments in conventional processes. However, the application and adaptation of the mass printing process for the printed electronics not only requires considerable know-how, but also a higher effort in comparison to the other printing processes, which, however, is still far below that in conventional electronics. While offset and flexographic printing are primarily used for inorganic ^{[9] [10]} and organic ^{[11] [12]} conductors (the latter also for dielectrics) ^[13] , gravure printing is particularly suitable for quality-sensitive layers due to the high layer quality that can be achieved such as organic semiconductors and semiconductor / dielectric boundary layers in transistors, ^[13] in connection with the high resolution, but also for inorganic ^[14] and organic ^[15] conductors. It could be shown that organic field effect transistors and integrated circuits ^[13] built from them can be completely manufactured using mass printing processes.

Inkjet printing

Inkjet printing is a flexible and versatile digital printing process that can be carried out with relatively little effort and also on a laboratory scale. Therefore, it is probably the most frequently used printing process for printed electronics, ^[16] however it is inferior to mass printing processes both in terms of area throughput (typically 100 m ² / h) and in terms of resolution (approx. 50 µm) . ^[5] It is particularly suitable for low-viscosity, dissolved materials such as organic semiconductors. In the case of highly viscous materials, such as organic dielectrics, and dispersed particles, such as inorganic metallic paints, difficulties repeatedly arise due to the clogging of the nozzles. Because of the dropwise application of the layers, their homogeneity is limited. Appropriate measures can be taken to alleviate these problems. By parallelization, ie the simultaneous use of many nozzles, or a pre-structuring of the substrate, improvements can also be achieved in terms of productivity or resolution. However, in the latter case, non-printing processes are used for the actual structuring step. ^[17] Inkjet printing is preferred for organic semiconductors in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs), but OFETs made entirely using this method have also been demonstrated. ^[18] Furthermore, front ^[19] and back planes ^[20] of OLED displays, integrated circuits, ^[21] organic photovoltaic cells (OPVCs) ^[22] and other components and assemblies can be produced using inkjet printing.

screen printing

Because of the possibility of producing thick layers of pasty materials, screen printing has been used on an industrial scale in the manufacture of electronics and electrical engineering for a long time. In particular, conductor tracks made of inorganic metals (e.g. for printed circuit boards, antennas or glucose test strips), but also insulating and passivation layers are produced with this method, whereby a comparatively high layer thickness, but not high resolution, is important. Area throughput (approx. 50 m ² / h) and resolution (approx. 100 µm) are limited, similar to inkjet printing. ^[5] This versatile and relatively simple process is also used in printed electronics, especially for conductive and dielectric layers, ^{[23] [24]} but organic semiconductors, e.g. B. for OPVCs, ^[25] and even complete OFETs ^{[19] can be} printed.

Other procedures

In addition to conventional processes, new processes are used that have similarities to printing, including microcontact printing and nanoprint lithography. ^[26] Layers with µm or nm resolution are produced in a process similar to stamping with soft or hard shapes. Often, the actual structures are subtractive, e.g. B. generated by the application of etching masks or by lift-off method. In this way, e.g. B. electrodes for OFETs. ^{[27] [28]} Pad printing is occasionally used in a similar manner. ^[29] Occasionally, the use of so-called transfer processes, in which solid structured layers are transferred from a carrier to the substrate, is counted among printed electronics. ^[30] Electrophotography (so-called toner or laser printing) has so far not been used in printed electronics.

materials

Both organic and inorganic materials are used for printed electronics. A prerequisite for this is, in addition to the respective electronic functionality, that the materials in liquid Form, ie as a solution, dispersion or suspension. ^[1] This applies in particular to many organic functional materials that are used as conductors, semiconductors or insulators. With a few exceptions, the inorganic materials are dispersions of metallic micro or nanoparticles. The starting point for the development of printable electronic functional materials was the discovery of conjugated polymers (Nobel Prize in Chemistry 2000) and their further development into soluble materials. ^[31] Today there is a large variety of printable materials from this class of polymers that have conductive, semiconducting, electroluminescent, photovoltaic and other functional properties. Other polymers are mostly used as insulator isolators or dielectrics.

In addition to the respective electronic functionality, processability in the printing process is essential for use in printed electronics. These two properties can conflict with each other, so that careful optimization is required. ^[6] For example, a higher molar mass of conductive polymers tends to have a positive effect on the conductivity of the printed layer, but has a negative effect on the solubility in the solvent used for printing. The properties of the liquid formulation, such as viscosity, surface tension and solids content, play a role in processing in the printing process, as well as interactions with previous or subsequent layers such as wetting, adhesion and mutual dissolving, as well as the drying process after deposition of the liquid layer . The use of additives to improve processability, as with conventional printing inks, is severely restricted in printed electronics, since these often impair the respective function.

The properties of the materials used largely determine the differences between printed and conventional electronics. On the one hand, the materials used in printed electronics offer a number of advantages that are crucial for the development of this technology. In addition to processability in liquid form, this includes mechanical flexibility and the possibility of adjusting functional properties through chemical modifications (e.g. the color of the light emitted in the active layer of OLEDs). ^[32] On the other hand, the highly ordered layers and interfaces, such as those used in inorganic electronics, cannot generally be produced from organic, in particular polymeric, materials. Among other things, this leads to the fact that the conductivity in printed conductors or the charge carrier mobility in printed semiconductors z. T. are far below the values in inorganic layers. ^[31] A point that is currently being intensively investigated is the fact that in most organic materials, hole conduction is preferred over electron conduction. ^[33] Recent studies indicate that this is a specific property of organic semiconductor / dielectric interfaces that play a central role in OFETs. ^[34] Therefore, could not have components n-type, are in contrast to p-type devices, printed, so that in the printed electronics not have a CMOS, but only PMOS technology is possible. Finally, the stability against environmental influences and the lifespan of printed electronic functional layers is typically lower than that of conventional materials. ^[35]

An essential characteristic of printed electronics is the use of flexible substrates, which has a favorable effect on the production costs and enables the production of mechanically flexible electronic applications.

While inkjet and screen printing still partially work on rigid substrates such as glass and silicon, the mass printing process almost exclusively uses film and paper due to its rotating process principle. Because of the cost advantage, polyethylene terephthalate film (PET) is often used, and because of the higher temperature stability, sometimes polyethylene naphthalate (PEN) and polyimide film (PI) are used. Other important criteria for the use of the substrate are low roughness and suitable wettability, which can be adapted by pretreatments (coating, corona treatment) if necessary. In contrast to conventional pressure, high absorbency generally has an unfavorable effect. Due to the low cost and the wide range of possible applications, paper is an attractive substrate for printed electronics, but it presents technological difficulties due to its high roughness and absorbency. Nevertheless, corresponding developments are underway. ^[36]

The most common materials used in printed electronics include the conductive polymers poly-3,4-ethylenedioxythiophene doped with polystyrene sulfonate (PEDOT: PSS) and polyaniline (PANI). Both polymers are commercially available in different formulations and have already been printed in inkjet, ^[37] screen ^[23] and offset printing ^[11] or in screen, ^[23] flexo ^[12] and gravure printing ^[15] . Alternatively, silver nanoparticles are used in flexographic, ^[10] offset, ^[36] and inkjet printing, ^[38] in the latter process also gold Particles, ^[39] used. In addition to the polymeric and metallic materials, carbon is also becoming a focus of this technology as a robust material for printed electronic applications. Numerous polymeric semiconductors are processed in inkjet printing, often using polythiophenes such as poly (3-hexylthiophene) (P3HT) ^[40] and poly-9,9-dioctylfluorobobithiophene (F8T2) ^[41] . The latter material has already been printed using gravure printing. ^[13] Various electroluminescent polymers are processed in inkjet printing, ^[17] as well as active materials for photovoltaics (e.g. mixtures of P3HT with fullerene derivatives), ^[42] some of which can also be applied using screen printing (e.g. B. Mixtures of polyphenylene vinylene with fullerene derivatives). ^[25] Printable organic and inorganic insulators or dielectrics exist in large numbers and can be processed in various printing processes.

Components and applications

• • OFETs, OLEDs und OPVCs,
• • ferner auch Dioden, verschiedene Arten von Sensoren, Speicherelementen und Anzeigesystemen sowie Antennen und Batterien.
• • Häufig werden Elektroden und andere leitfähige Schichten in den Bauelementen gedruckt. Insbesondere die Herstellung der Source/Drain-Elektroden von OFETs im Inkjetdruck^[43] und mittels Massendruckverfahren^[11] ist Gegenstand intensiver Entwicklungen.
• • In OLEDs^[37] und OPVCs^[22] wird PEDOT:PSS als Beschichtung für die Anode bzw. als Anode selbst verwendet und kann im Inkjetdruck aufgetragen werden. In diesen beiden Bauelementen stellt der Druck der Kathode mangels geeigneter druckbarer Materialien noch eine große Herausforderung dar.
• • Ebenso sind im Siebdruck aus metallhaltiger Farbe hergestellte RFID-Antennen in kommerziellen Systemen z. B. zum Diebstahlsschutz zu finden.
• • Des Weiteren werden auch die Halbleiterschichten in den Bauelementen mittels Druckverfahren hergestellt. So werden beispielsweise der Inkjet-^[40] und der Tiefdruck^[13] für die aktive Schicht von OFETs und der Inkjet-^[42] bzw. Siebdruck^[25] für die von OLEDs bzw. OPVCs eingesetzt. Vollständig gedruckte OFETs konnten im Inkjet-^[18] und Siebdruck^[19] sowie mittels Massendruckverfahren^[13] hergestellt werden, im letztgenannten Fall wurde auch eine vollständig gedruckte integrierte Schaltung aus mehreren OFETs demonstriert.

Almost all components required for electronic applications are also manufactured in printed electronics. Current developments focus on:

• OFETs, OLEDs and OPVCs,
• • also diodes, various types of sensors, memory elements and display systems as well as antennas and batteries.
• • Electrodes and other conductive layers are often printed in the components. In particular, the production of the source / drain electrodes of OFETs in inkjet printing ^[43] and by means of mass printing processes ^[11] is the subject of intensive developments.
• • In OLEDs ^[37] and OPVCs ^[22] , PEDOT: PSS is used as a coating for the anode or as the anode itself and can be applied in inkjet printing. In these two components, the pressure of the cathode is still a great challenge due to the lack of suitable printable materials.
• • Likewise, RFID antennas made of metal-based ink are used in commercial systems in commercial systems. B. to find theft protection.
• • Furthermore, the semiconductor layers in the components are also produced using printing processes. For example, inkjet ^[40] and gravure ^{[13] are used} for the active layer of OFETs and inkjet ^[42] or screen printing ^[25] for those of OLEDs and OPVCs. Fully printed OFETs could be produced by inkjet ^[18] and screen printing ^[19] as well as by mass printing ^[13] . In the latter case, a fully printed integrated circuit consisting of several OFETs was also demonstrated.

Integrated circuits made of OFETs, OLED displays and solar cells based on OPVCs, which are produced using printing processes, as well as other printed components and assemblies are to be used wherever the specific properties of printed electronics are advantageous, i. H. wherever simple, inexpensive, flexible and large-area electronic components are required.

The use of printed RFID tags is often discussed in this context, since the printed electronics should enable the manufacture and integration of such systems at a significantly lower cost than conventional systems, so that large quantities of everyday products can also be equipped (so-called single-item -tagging) is possible. In this vision, printed RFID tags will replace the barcode previously used to identify goods.

On organic, e.g. RFID circuits based on liquid-processable materials have also been demonstrated, ^{[44] [45]} but the performance of printed circuits is not yet sufficient for this application. ^{[29] In} contrast, simpler, fully printed identification systems can already be found in applications on the market.

In the field of OLED displays, organic electronics is the most advanced in terms of commercial products. Intensive efforts are aimed at further reducing manufacturing costs through the use of printing processes. ^{[17] In} addition to the pressure of the cathode, the integration of the control electronics (backplane) represents a major challenge. The visions associated with this are primarily flexible and rollable displays and large, flexible and thin illuminants.

In the area of organic electronics, other display systems with similar functions, such as. B. the e-paper developed, the z. T. are about to be launched on the market and will also be manufactured in the future using printing processes. ^[46]

Large and flexible organic solar cells printed on inexpensive substrates are another vision, the realization of which is being promoted in the context of printed electronics. ^[47] However, there are still a number of issues to be dealt with, in addition to the pressure of the cathode, for example, an increase in efficiency is necessary for economical operation.

In general, it is assumed that a few years will pass before the visions associated with printed electronics can be realized, but in the meantime, increasingly simple applications will become established. Not least because of the possibility of easy integration of numerous functionalities, printed electronics is regarded as one of the key technologies for the implementation of new paradigms for the application of electronics, which aim at stronger networking and more extensive penetration in many areas of life and with the keywords such as "ubiquitous computing" and "ambient intelligence" are connected.

Development of printed electronics

• • vor 1986: Siebdruck von metallhaltigen Farben für Leiterbahnen in Elektrotechnik/Elektronik, Verwendung von PEDOT:PSS als Antistatikbeschichtung, Verwendung organischer Photoleiter in der Elektrofotografie
• • 1986: OFET^[48]
• • 1986: OPVC^[49]
• • 1987: OLED^[50]
• • 1990: OFET mit flüssigprozessierter aktiver Schicht
• • 1990: OLED mit flüssigprozessierter aktiver Schicht^[51]
• • 1994: OFET auf flexiblem Substrat^[52]
• • 1997: OFET mit im Siebdruck hergestellter aktiver Schicht^[24]
• • 1998: OLED mit im Inkjetdruck hergestellter Elektrode^[37]
• • 1998: integriertes OLED/OFET-Pixel mit flüssigprozessierten aktiven Schichten^[53]
• • 1998: OLED mit im Inkjetdruck hergestellter aktiver Schicht^[54]
• • 1999: OPVC auf flexiblem Substrat^[55]
• • 2000: OFET mit im Inkjetdruck hergestellten Elektroden^[21]
• • 2000: OLED auf flexiblem Substrat^[56]
• • 2001: OFET mit im Inkjetdruck hergestellter aktiver Schicht^[40]
• • 2001: vollständig im Siebdruck hergestellter OFET^[19]
• • 2001: OPVC mit flüssigprozessierter aktiver Schicht^[57]
• • 2001: OPVC mit im Siebdruck hergestellter aktiver Schicht^[25]
• • 2004: OPVC mit im Inkjetdruck hergestellter Elektrode und aktiver Schicht^[22]
• • 2005: vollständig im Inkjetdruck hergestellter OFET^[18]
• • 2005: OFET mit im Offsetdruck hergestellten Elektroden aus PEDOT:PSS^[11]
• • 2007: vollständig mit Massendruckverfahren hergestellte integrierte Schaltung^[13]

The development of printed electronics is closely linked to that of organic electronics. Some important milestones in this development are listed below.

• • before 1986: screen printing of metal-containing inks for printed conductors in electrical engineering / electronics, use of PEDOT: PSS as an antistatic coating, use of organic photoconductors in electrophotography
• 1986: OFET ^[48]
• 1986: OPVC ^[49]
• 1987: OLED ^[50]
• • 1990: OFET with a liquid-processed active layer
• • 1990: OLED with liquid-processed active layer ^[51]
• • 1994: OFET on flexible substrate ^[52]
• • 1997: OFET with an active layer produced by screen printing ^[24]
• • 1998: OLED with electrode produced in inkjet printing ^[37]
• • 1998: Integrated OLED / OFET pixel with liquid-processed active layers ^[53]
• • 1998: OLED with active layer produced in inkjet printing ^[54]
• • 1999: OPVC on flexible substrate ^[55]
• • 2000: OFET with electrodes manufactured in inkjet printing ^[21]
• • 2000: OLED on flexible substrate ^[56]
• • 2001: OFET with an active layer produced in inkjet printing ^[40]
• • 2001: OFET made entirely by screen printing ^[19]
• • 2001: OPVC with liquid-processed active layer ^[57]
• • 2001: OPVC with active layer produced by screen printing ^[25]
• • 2004: OPVC with electrode produced in inkjet printing and active layer ^[22]
• • 2005: OFET produced entirely in inkjet printing ^[18]
• • 2005: OFET with electrodes made of PEDOT: PSS ^[11]
• • 2007: Integrated circuit manufactured entirely with mass printing processes ^[13]

Pink

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P-Ink ("photonic ink") is a technology that is used in thin and flexible - electronically controlled - displays, whereby the generation of colors is controlled by photonic crystals.

The color to be displayed is controlled by the distance between the crystals. Depending on this distance, the crystal can only be penetrated by light with a certain wavelength and can be reflected by the reflection layer behind it. If no voltage is applied, the condition of the crystals and thus the display is maintained for several days, which means that displays with P-Ink technology only require electrical power when the display is switched.

Principle of operation of P-Ink

The advantage of P-Ink compared to most other display technologies is that a single image pixel can display several colors at the same time without loss of brightness. ^{[1] [2]}

The principle was developed at the University of Toronto. In order to be able to develop the technology to market maturity, the company Opalux was founded.

MicroLED

MikroLED - also called MicroLED, mLED or µLED - is a flat screen technology based on light-emitting diodes (LED). As the name implies, microLEDs are based on arrays of microscopic light-emitting diodes (LEDs) that form the individual picture elements (pixels).

Compared to the older liquid crystal displays (LCDs), MicroLED displays offer a significantly higher contrast, significantly faster response times and a higher efficiency in terms of luminous flux per output. MicroLEDs (µLEDs) are the successors of the organic light-emitting diodes OLEDs. ^[1] In contrast to the existing carbon OLEDs μLEDs made of indium gallium nitride InGaN ^[2]. Inorganic semiconductors based on µLEDs were first developed by a research group around Hongxing Jiang and Jingyu Lin from Texas Tech University in 2000. ^[3]

Because of their low energy consumption, µLEDs are suitable for very small displays, such as smartwatches and smartphones, as well as very large displays, such as giant television screens.

LCD is the plasma or the tube of tomorrow: a technology that will be replaced by one or more. Hot-traded candidates for this are LED, OLED and MicroLED (other internationally used abbreviations: Micro-LED, mLED or µLED). MicroLED was first introduced by researchers in 2000. Like OLED, mLED can score with absolutely excellent black and contrast values. In addition, µLED is very durable and energy-efficient, which is particularly interesting in professional scenarios (operating and running times, maintenance and electricity costs). In contrast to OLED, MicroLED is based on GaN, i.e. an LED technology. Compared to OLED, mLED supporters point to a longer lifespan and the high luminance of the self-illuminating LEDs.

At the current CES 2018, Samsung has now presented a consumer product in the high-end price segment, which once again shows that at least the large Korean manufacturer MicroLED considers one of the future technologies - namely screens in all possible sizes and B2C and B2B -Applications: "The Wall", a 146 "mLED-TV, the world's first modular in this class. The advantage is obvious: As with LED walls, modules can be built or personalized very theoretically in any shape from modules.

In recent years, Chinese manufacturers have also presented the first TVs with LED modules as a proof-of-concept, but mostly only on the domestic market. The world's first micro LED TV is the prototype of a 55 "Full HD" Crystal TV "that Sony launched in 2012. It is considered the ancestor of the CLEDIS (canvas display). The self-emitting technology CLEDIS uses ultra-fine LEDs with R (red ), G (green) and B (blue) on the display surface, each pixel consists of a separate ultrafine R, G and B LED and the light source is only 0.003 mm2. The remaining area is more than 99% black.

For business-to-business applications, both Samsung and other players such as Sony have launched the first products that use MicroLED architectures: Sony has its CLEDIS solution, Samsung has the cinema LED screen. Both groups rely on extremely small, self-illuminating LEDs. While CLEDIS was already convincing in effect at ISE 2017, other manufacturers could also show new MicroLED products at the trade fair in February 2018. Samsung is at least a candidate for this - but is currently not commenting on the topic.

Should, would have, supply chain: There is more than one indication from the supply chain of the display industry that µLED could still be used in specific digital signage products this year - of course no guarantee, but strong evidence. Because the 146 "MicroLED TV from Samsung now shown was expected according to market rumors from autumn 2017, but as a 150" TV.

For the first time in May 2017 and then in autumn 2017, there were market rumors that Samsung would buy or participate in the Taiwanese mLED specialist PlayNitride Inc. founded in 2014. While PlayNitride denied this, Samsung did not comment on the reports. At the end of 2017, PlayNitrides said that there were purchase offers from several companies. So far, LED expert Epistar and the Taiwanese semiconductor manufacturer United Microelectronics Corporation (UMC) have been the only known shareholders of PlayNitride.

But even without a purchase, Samsung relies on µLED: In-house developments and possible licensing make this possible. As can be seen in the case of the LED cinema screen, the group has already launched a product ready for series production - and into the real world of project installations.

The usually more than well-informed industry service Digitimes recently reported about another manufacturer that has specific MicroLED products in the pipeline, the South Korean manufacturer Lumens (not to be confused with the Taiwanese manufacturer Lumens of similar name, who will be among the exhibitors at ISE 2018 becomes).

According to the Digitimes report, industry sources speak of the development of 0.57 "MicroLED screens up to a 100" digital signage screen that should use 100 to 300 micron "large" µLED modules.

Whether at the ISE or at the InfoComm or one of the major Asian trade fairs: One should not be too surprised when the first large display manufacturer presents a MicroLED digital signage screen this year - for example in the class of 98 "large format displays.

LED TV

LED televisions are television sets in which light-emitting diodes (LEDs) are used either for backlighting or for generating the picture itself. The following definition also applies to most computer monitors, which use very similar technology to display images. Most of them are LC displays (LCDs) whose backlighting consists of light-emitting diodes (see LED backlighting). For this purpose, both white and miscible colored LEDs are used, which are arranged behind the liquid crystal display. The term “LED TV” is misleading with this type of display technology, but it is common. Such devices should correctly be referred to as "LED-backlit LCD televisions".

Comparison scheme LCD / LED

Until about 2008, essentially only three different technologies for home use were offered, namely liquid crystal screens, plasma screens and projection displays. Because liquid crystal displays only modulate the light, ie how light valves work and do not emit light themselves, flat lighting is installed behind the liquid crystal display for television sets in order to display the image information in transmitted light (transmission). In the simplified diagram opposite, such liquid crystal screens are designated as display types A and B, the liquid crystal display 1 modulating the light in accordance with the image to be displayed. ^[1]

Since about 2009, LED TVs and LED monitors have been advertised in stores (diagram type B). Up to 2013, it was still practically all of the previous liquid crystal displays for image generation. The only new feature is the backlighting of these LCD televisions by means of light-emitting diodes (English LEDs; scheme: part 3, whereby a light distributor (not shown) ensures areal illumination).

Backlighting techniques comparison

• • kompaktere Bauweise mit geringerer Tiefe des Gerätes
• • geringerer Stromverbrauch bei niedrigeren elektrischen Spannungen
• • kürzere Schaltzeiten (siehe dynamische Leuchtdiodenansteuerung)
• • geringere Abnahme der Lichtintensität und Veränderung des Farbspektrums im Laufe der Nutzung
• • höhere Zuverlässigkeit und Lebensdauer.

Until about 2008, cold cathode tubes (fluorescent tubes) were used almost exclusively as backlighting in LCD televisions (scheme: part 2 in combination with a flat light distributor, not shown). The use of LEDs (scheme: part 3) instead of fluorescent tubes is emphasized in the product advertising because the following advantages over the previous technology exist: ^[2]

• • more compact design with less depth of the device
• • lower power consumption with lower electrical voltages
• • Shorter switching times (see dynamic LED control)
• • less decrease in light intensity and change in the color spectrum in the course of use
• • higher reliability and durability.

Use of RGB combinations

There are additional advantages with special versions of the light-emitting diodes: Here, several assembled red, green and blue light-emitting diode combinations are distributed behind the display area (additive color mixing, full-array LED). This type of lighting, matched to the color filters of the liquid crystal display, results in a better color spectrum for the television set, but is more expensive than the use of light-emitting diodes along the edge of the screen (edge-lit).

Quantum dots for an optimal color spectrum
→ Main article: quantum dot LED

With the help of nano-semiconductor crystals (quantum dots), applied as a layer on a glass plate or foil and illuminated by blue, short-wave LEDs (e.g. made of GaN) from behind, the spectrum of the backlighting of LCDs can be reached to a previously unattained level Art can be optimized (technical expression extended color space). This form of fluorescence technology is being further developed in various laboratories. ^[3] The US company 3M as major supplier of backlight components for LCDs works with Nanosys, Inc. accordingly coated films. ^[4] The British company Nanoco Group PLC has also been working on the further development of quantum dots for several years and has concluded cooperation agreements with Asian manufacturers of liquid crystal displays and OLEDs. The US company QD Vision also works with Asian companies that optimize the backlighting of LC displays. ^[5]

In 2013, Sony was the first company to launch certain high-quality LCD televisions with such optimized LED backlighting under the name Triluminos, which was used earlier. ^[6] The light from blue LEDs on a glass pane or film attached in front of it is converted into very pure, narrow-band blue, green and red by different quantum dots. The combination of these three basic colors creates an optimal white illumination of the LC display from behind. ^[7] Since then, improved LCD TV with LED backlight by quantum dots layer and presented at the CES trade show in 2015, the Korean company Samsung Electronics, LG Electronics, as well as Chinese TV manufacturers (TCL, Changhong, Hisense). ^{[8] [9] [10] In} 2016 Samsung Electronics decided to re-market their high-quality televisions with the name QLED in order to point out the technology with quantum dots. This should also prepare the transition to the new screens with self-illuminating QLEDs, which are still being developed at Samsung. ^{[11] [12]}

Dynamic LED control depending on the image content

Previous liquid crystal screens had a limited contrast because the representation of a black pixel (pixel) was not completely dark due to the still somewhat translucent background lighting. By selective control of the distributed light emitting diodes depending on the image content, dark parts can be made darker by the reduced local lighting (local dimming) and therefore the Contrast can be increased. The number of distributed light-emitting diodes (scheme B: part 3) is much smaller than the number of pixels of the liquid crystal display. Therefore, the aforementioned increase in contrast cannot be achieved individually for each pixel, but only for a larger group of neighboring pixels. Nevertheless, the best contrast of all LCD televisions can be achieved with this technology. However, only a few devices are commercially available with this relatively expensive backlight as a combination of full-array LEDs with local dimming.

Real LED displays with monolithic LEDs

Inorganic, monolithically manufactured, single-crystal light-emitting diodes have been used as display elements since the early 1970s. ^[13] Examples were the PULSAR wristwatches with a red digital display and the first pocket calculator. Many details and notes can be found in the article LED. The development of blue LEDs brought about a breakthrough because it made possible combinations of LEDs to generate white light. ^[14]

Monolithic LEDs are manufactured on single-crystalline semiconductor wafers. These round disks produced by crystal growth have a diameter of up to 30 cm. If all other problems were resolved, it would not be possible to produce larger monolithic LED screens. In practice, individual LEDs are obtained from this by cutting the pane and making individual electrical contacts.

Large outdoor screens (e.g. in football stadiums, video wall) are implemented with a large number of individual light-emitting diodes.

So-called micro-LED displays follow a new approach. Micro LED arrays are also manufactured monolithically in a batch process on a suitable substrate made of sapphire or silicon. The preferred material is inorganic monocrystalline gallium nitride (GaN), which is formed on the substrate by epitaxy. ^[15] Unlike the previous production, however, the LEDs are then not severed, but kept as a display matrix.

The novel structure required for this, with multiple challenges such as doping for different colors, contacting as a matrix arrangement, mechanical stability during transfer from the manufacturing substrate to a display substrate have not yet been solved in such a way that such displays can be used for commercial products. Apple Inc. sees potential in this new technology and has therefore taken over the pioneering company LuxVue Technology. ^{[16] [17]}

Displays with organic light emitting diodes (OLEDs)

• • OLEDs strahlen selbst Licht ab, brauchen somit keine Hintergrundbeleuchtung und bieten hohen Kontrast.
• • potentiell niederigere Herstellungskosten grosser Bildschirme als noch 2017^[19] und geringerer Stromverbrauch bei Einsatz des Herstellverfahrens mittels Metallmaske^[19][20]
• • OLEDs können in verschiedenen Farben Licht abgeben, während bei LCDs dafür zusätzliche Farbfilter notwendig sind.
• • geringere Winkelabhängigkeit beim Betrachten
• • kürzere elektrooptische Ansprechzeiten.

Electroluminescence in layers of organic material has been researched since the 1950s. ^[18] In the meantime, organic semiconductor materials have been developed as OLEDs, which are suitable as display elements in thin-film technology. This technique is shown in simplified form as display type C in the diagram. The OLEDs 4 are applied on a substrate (or between two substrates) in such a dense manner using thin-film technology that they serve as individual pixels for image generation. Advantages over liquid crystal displays are:

• • OLEDs emit light themselves and therefore do not need any backlighting and offer high contrast.
• • potentially lower production costs for large screens than in 2017 ^[19] and lower power consumption when using the manufacturing process using a metal mask ^{[19] [20]}
• • OLEDs can emit light in different colors, while additional color filters are required for LCDs.
• • less angle dependence when viewing
• • shorter electro-optical response times.

The main disadvantage is the limited lifespan. ^[21] Further disadvantages are the UV sensitivity and the currently high manufacturing costs. ^[19] Samsung Electronics, as a major manufacturer of both liquid crystal and OLED displays, decided in 2016 to forego OLEDs for future large-format televisions. In addition to the disadvantages mentioned, burn-in also occurs with OLEDs certain pattern mentioned as another disadvantage. ^{[22] [23]} The manufacturer uses - in contrast to the competition - QLEDs instead of OLEDs in television technology. ^[24]

Such displays are used to equip many small to medium-sized portable devices such as digital cameras, smartphones (e.g. Samsung Galaxy S), tablets and laptops. In January 2012, the first prototypes of 55-inch OLED televisions from LG Display and Samsung were shown at the Consumer Electronics Show (CES) in Las Vegas. ^[25] OLED screens have now become widely available on large format televisions. These displays are often summarized under the term AMOLED (active matrix organic light emitting diode).

Organic light emitting diode

An organic light-emitting diode (OLED) is a luminous thin-film component made of organic semiconducting materials, which differs from inorganic light-emitting diodes (LED) in that the electrical current density and luminance are lower and no single-crystal materials are required. Compared to conventional (inorganic) light-emitting diodes, organic light-emitting diodes can therefore be manufactured more cost-effectively using thin-film technology, but their lifespan and light output are lower than that of conventional light-emitting diodes.

OLED technology is used for screens in smartphones, tablet computers as well as in large-screen TVs and computer monitors. Another area of application is large area lighting. Due to the material properties, a possible use of the OLEDs as a flexible screen is also interesting.

OLED display

In the 1950s, electroluminescence in organic materials was discovered by A. Bernanose at the University of Nancy in France. Substances such as acridine orange were deposited or dissolved in thin films of cellulose or cellophane and exposed to an alternating current field. This mechanism is based on the direct excitation of dye molecules or electrons. ^{[1] [2] [3] [4]}

In 1960 Martin Pope and co-workers at New York University developed ohmic electrode contacts for injecting charge carriers into organic crystals in the non-illuminated state. ^{[5] [6] [7]} Furthermore, they described the necessary energy requirements (work functions) for electrode contacts that can inject electrons or holes (defect electrons) into an organic semiconductor. Such contacts are the basis for charge injection in all modern OLED devices.

In 1963 Pope's group also discovered the first direct voltage (DC) luminescence under vacuum on a pure anthracene single crystal and on tetra-doped anthracene crystals with a small silver electrode at 400 V. ^[8] This mechanism is based on field-accelerated electron excitation of molecular fluorescence. In 1965, Pope's group reported on the one hand electroluminescence in anthracene crystals, triggered by the recombination of thermalized electrons and holes without an external electric field, ^[9] and on the other hand that the leading energy level for anthracene is higher than the exciton energy level.

Also in 1965, Wolfgang Helfrich and WG Schneider from the National Research Council of Canada produced electroluminescence by double-injected recombination for the first time in an anthracene single crystal using hole and electron-injecting electrodes, ^[10] the forerunners of modern double-injecting devices .

In the same year, researchers at Dow Chemical patented a process in 1965 for producing electroluminescent cells from an electrically insulated, 1 mm thin film of molten phosphorus with incorporated anthracene powder, tetracene and graphite powder, which was operated with alternating voltage (100-3000 Hz, 500-1500 V ) was operated. ^[11] This mechanism is based on electronic excitation of graphite and anthracene molecules on the contacts.

The performance was limited by the poor electrical conductivity of the organic materials at that time. This limitation has been improved by the discovery and development of highly conductive polymers. ^[12] So watching Roger Partridge from the UK's National Physical Laboratory in 1975 for the first time electroluminescence of polymer films. The later patented ^[13] and 1983 in a trade journal published ^{[14] [15] [16] [17]} structure consisted of an up to 2.2 µm thin film of poly (N-vinyl carbazole) between two charge-injecting electrodes.

Ching W. Tang and Steven Van Slyke of the Eastman Kodak Company first reported a diode design in 1987. ^[18] A novel two-layer structure with a separate hole and electron-transporting layer was used, so that recombination and light emission occurred in the middle of the organic layer. This led to a lower operating voltage and higher efficiency and represented the transition to today's OLED research and production.

In 1990, JH Burroughes and co-workers from the University of Cambridge developed an efficient green light-emitting device using 100 nm thin film of poly (p-phenylene-vinylene). ^In 1996, the first device with a luminous polymer from Cambridge Display Technology (CDT) was introduced. ^[20] In November 2006, scientists at the Pacific Northwest National Laboratory (PNNL) created a blue OLED with a quantum yield of 11% at 800 cd / m ² . ^{[12] [21]}

Structure and functionality

Scheme of an OLED: 1. cathode, 2. emitter layer, shown in green, 3. recombination of the charge carriers with emission of a photon, 4. hole line layer, 5. anode

OLEDs are made up of several layers. A hole transport layer (HTL) is usually applied to the anode consisting of indium tin oxide (ITO), which is located on a glass pane. Depending on the manufacturing method, a layer of PEDOT / PSS is often applied between ITO and HTL, which serves to lower the injection barrier for holes and prevent indium from diffusing into the transition. A layer is applied to the HTL, which either contains the organic dye (5 to 10 percent) or - rather rarely - consists entirely of the dye, e.g. B. Aluminum tris (8-hydroxyquinoline), Alq3. This layer is known as the emitter layer (EL). An electron transport layer (ETL) is optionally applied to this. Finally, a cathode consisting of a metal or an alloy with a low electron work function, such as calcium, aluminum, barium, ruthenium, magnesium-silver alloy, is evaporated in a high vacuum. As a protective layer and to reduce the injection barrier for electrons, a very thin layer of lithium fluoride, cesium fluoride or silver is usually evaporated between cathode and E (T) L.

The electrons (ie the negative charge carriers) are now injected from the cathode while the anode provides the holes (ie the positive charge carriers). Electrons and holes drift towards each other and ideally meet in the EL, which is why this layer is also called the recombination layer. Electrons and holes form a bound state, which is called an exciton. Depending on the mechanism, the exciton already represents the excited state of the dye molecule, or the decay of the exciton provides the energy to excite the dye molecule. This dye has different states of excitation. The excited state can change to the ground state and thereby emit a photon (light particle). The color of the emitted light depends on the energy gap between the excited and the ground state and can be specifically changed by varying the dye molecules. Non-radiative triplet states represent a problem. These can be resolved by adding so-called “exciters”. ^{[22] [23]}

Use and selection of organic materials

The abbreviation PLED (polymer light emitting diode) has become established for the organic LEDs made from polymers. The OLEDs made from “small molecules” are less often referred to as SOLED or SMOLED. Derivatives of poly (p-phenylene-vinylene) (PPV) are frequently used as dyes in PLEDs. Dye molecules have recently been used which are expected to be four times more efficient than with the fluorescent molecules described above. These more efficient OLEDs use organometallic complexes in which the light is emitted from triplet states (phosphorescence). ^[24]

These molecules are also called triplet emitters; ^{[25] [26]} the dye can also be excited by ambient light, which can lead to luminescence. However, the goal is to produce self-illuminating screens that use organic electroluminescence. ^[27]

In recent years, simulation techniques have been developed that can now calculate the important properties of OLEDs completely on the computer based on their chemical composition. ^{[28] [29]} These methods allow an inexpensive pre-selection of molecules without complex synthesis and experimental characterization.

Manufacturing process for AMOLED screens

AMOLED (active matrix OLED) screens have two important manufacturing processes that determine the production costs, the technical properties and thus the field of application. ^[30] On the one hand there are RGB side-by-side AMOLED screens (SBS) based, among other things, on fine metal mask (FMM) technology and on the other hand white OLEDs with a color filter (WOLED). ^[31]

RGB-SBS-AMOLED screens are designed so that each sub-pixel emits one of the three primary colors red, green or blue. ^[31] The advantages lie in a large color space (> 100% NTSC) ^[32] and a low power consumption compared to WOLED screens. ^[32] However, the manufacturing process and the different rapid aging of the subpixels have a disadvantageous effect. During the manufacture of the SBS-AMOLEDs, the pixels are placed through a fine metal mask (FMM) or applied to the substrate. The high accuracy with which the mask must be aligned is problematic here (± 1 µm). ^[33] Especially with high resolutions and large screens, this often leads to manufacturing errors, which leads to high rejects and high costs. ^[33] This technology is therefore used on small screens such as smartphones. Samsung is a big manufacturer here. ^[34]

In contrast, WOLED technology does not produce sub-pixels of different colors. FMM is not used. With this technique, white emitted light meets a color filter that selects the primary colors per pixel. ^[35] Due to the lack of FMM, production is also possible in large quantities with large screens. Color shifts due to subpixels aging at different speeds do not occur here. However, the power consumption is higher due to the light-absorbing color filter and the color space can be smaller than with SBS-AMOLEDs. ^[35] LG, for example, uses WOLED technology in television sets. ^[36]

advantages

Printed OLED line, lit with a battery

One advantage of OLED screens over conventional liquid crystal screens (LCDs) is the very high contrast, since they do not need backlighting: black pixels do not emit light. While LCDs only act as colored filters and some light shines through in the dark, OLEDs only emit colored light when activated, which also promises very good color reproduction. This method is significantly more efficient, which means that OLEDs, especially when displaying dark images, require less energy. For this reason, OLED devices are less warm than corresponding devices with LC screens, although the switch from cold cathode tubes to LEDs for LCD backlighting has reduced the energy required for liquid crystal screens. Due to the low energy consumption, OLEDs can be used well in small, portable devices such as notebooks, cell phones and MP3 players. Because the backlight is not required, OLEDs can be made very thin. A Sony model presented at “Display 2008” has a depth of only 0.3 millimeters. ^[37]

The response time of OLED screens for some devices is less than 1 microsecond ^[38] , which is around 1000 times faster than the currently fastest LCD with one millisecond.

One advantage is based on the possibility of producing OLEDs over a large area using printing technology, which does not require expensive vacuum and clean room conditions. The cost advantage arises from the fact that the electrically conductive coloring layers can be applied in a modified inkjet printing process or, more recently, also in offset printing and can also be subsequently coated without vacuum evaporation. DuPont ^{[39] [40]} and Merck are leaders in this field of soluble OLED material systems. ^[41] The first OLEDs were printed in 1987 under laboratory conditions. The leading trade fair and congress for printed electronics is the LOPEC trade fair in Munich every year. ^[42] At Drupa 2012, the leading trade fair for the printing industry, printed OLEDs were sold as a billion dollar market

The biggest technical problem is the comparatively short lifespan of some components made of organic materials. For (O) LEDs, the term lifespan is the middle one Operating time after which the luminance has halved. Blue OLEDs have the lowest lifespan. For white light sources, such as monitors, the blue component is the limiting factor for the total usable life. In 2011, 5000 hours (at 1000 cd / m ² ) ^[44] and 12,000 hours (at 100 cd / m ² ) ^{[45] were} specified for white light sources. In comparison, commercially available white LEDs for backlighting LCD monitors have an average operating time of around 30,000 hours. ^[46]

The lifespan of OLEDs is temperature-dependent: A well-cooled OLED (no matter what color) with a low initial luminosity always has a longer lifespan than an OLED that is operated at maximum luminosity from the start without cooling. The reason is diffusion processes in the OLED, which run faster at higher temperatures. The service life at medium to low brightness is extrapolated from the value at maximum brightness, since the test of OLED materials at low luminosity over several tens to a few hundreds of thousands of hours is not practical.

Another disadvantage of OLEDs is the lower luminous efficacy in the range of 40 Im / W to 60 Im / W compared to light-emitting diodes with commercially available OLEDs. Peak values from selected laboratory samples for OLEDs achieve values just over 100 Im / W. ^[47] Conventional light-emitting diodes for lighting purposes achieve values of 200 Im / W, with specially optimized LEDs up to just over 300 Im / W. ^[48]

In addition to a shorter lifespan and light output, OLEDs are also sensitive to certain external substances. In addition to water, ubiquitous humidity can also destroy penetrating oxygen. It is therefore important to hermetically encapsulate the display and protect it from external influences. The necessary rigid encapsulation affects flexibility. Corrosion with oxygen puts the highly reactive injection layer made of calcium and barium at risk. Typical signs of failure are circular, growing non-luminous areas, so-called “dark spots”. The cause is often a particle load when the metal layers are evaporated. The microscopic edges of the multilayer structure are also infiltrated by corrosion, which leads to a decrease in the effective luminous pixel area in screen applications.

As of 2017, commercial OLEDs on flexible substrates are in the introductory phase because all flexible plastic substrates have a high permeability to oxygen and air humidity. Very thin glass (glass with a thickness of at most about 0.2 mm) is difficult to handle in processing, and the anode material indium tin oxide is a hard and brittle material. Repeated rolling in and out by a small radius leads to breakage and rapid failure (increase in resistance) of the anode.

In many applications, OLEDs could replace the LCDs and plasma screens common today. The lifespan gives up some problems, because the red, green and blue luminous dots age at different speeds. This irregular aging of the individual colors leads to color shifts in the overall image over time, which can only be compensated for to a limited extent by an - ideally automatic - readjustment (above all by increasing the blue emission).

The basic patents for OLED structures date from the 1980s. Kodak was the leader. Around 6,600 patents have been known on the subject since 1980. The main areas of research are in Japan, South Korea and the USA. Most of the patents are registered in Japan, followed by the United States and Europe. Germany is in third place with about 4.5% behind the USA with about 22%.

Since self-illuminating OLED displays are even more expensive than backlit LC displays, they have so far only been used in special applications. Because of the smaller dimensions, they offer greater design freedom for the device manufacturer. The power consumption of the OLEDs is also often lower because they do not require any backlighting.

Large OLED screens have so far been more expensive than correspondingly large LCD screens. Problems are primarily the encapsulation of the components and the more complex control of the pixels. With LCDs, control is carried out with low power, since LCD pixels are only reversed as electrical capacitances by an applied voltage, the light energy is generated by the backlight. In contrast, OLEDs themselves have to be supplied with the energy required for the light emission in order to generate electroluminescence. They are current-controlled, which is why the mature technology used up to now cannot be transferred directly from the LCD area.

In the case of small OLED screens, control can take place via a so-called passive matrix: a certain pixel is controlled by applying a voltage to a row and column, which requires two lines. This method is not sufficient for large screens because the path resistances increase linearly with the size and therefore the driving force is no longer sufficient to control the respective pixel. To control the screen, an active matrix must be used here, in which each pixel is addressed individually via its own transistor, which requires four lines; Derived from active matrix organic light emitting diode (OLED), the technology is sold under the terms AMOLED and SuperAMOLED. The provision of switching (voltage signals) as well as supply current (as with plasma screens) is complex and therefore expensive and one of the main reasons for the high cost of large screens.

Color displays with AMOLEDs in a PenTile matrix arrangement can be used for the invention.

The most regarded technology is Super AMOLED +. Here the PenTile matrix was removed so that every pixel has all three primary colors available. Accordingly, without a pentile matrix, several pixels are no longer “connected” to mix all colors. Due to this change, the resolution of such displays appears significantly higher, and no individual pixels stand out. Further improvements include better black levels, increased contrast, more displayable colors, lower power consumption and reduced thickness of the display. However, the PenTile effect is hardly noticeable at very high pixel densities of well over 300 ppi (pixels per inch) or if you look closely. This is one of the reasons why Samsung can still use SuperAMOLED screens with newer products for Full HD without having to fear a reduced quality.

Manufacturer

Important manufacturers of lamps using OLED technology are Osram, Konica-Minolta and OLEDWorks, while LG, Samsung SDI and AU Optronics are important manufacturers of OLED information displays. There are also a large number of other manufacturers. ^[49] Philips and Osram left the display business in 2004 and 2007, respectively, and now only produce OLED lamps. ^{[50] [51]} In mid-2015, Philips withdrew from OLED production and sold the production facility to OLED Works in Rochester, NY, USA. ^[52]

In June 2015, the pharmaceutical and specialty chemicals manufacturer Merck KGaA laid the foundation stone for a new plant at its headquarters in Darmstadt, which is to produce the necessary chemical basic elements for the OLED technology for the international OLED electronics manufacturers. The cost of the new factory was 30 million euros. The plant went into operation in September 2016. ^[53]

In November 2015, the LG Group announced that it would build a plant for OLEDs in South Korea, which should start production in the first half of 2018. The investment costs are said to be 8.2 billion euros. ^[54]

During 2016, Samsung Electronics, as a major manufacturer and user of AMOLEDs, announced that in the future large-screen TV screens would no longer be manufactured using OLED technology. In addition to a limited lifespan, image burn-in phenomena and relatively high production costs are mentioned as reasons. ^{[55] [56]}

LCD is the plasma or the tube of tomorrow: a technology that will be replaced by one or more. Hot-traded candidates for this are LED, OLED and MicroLED (other internationally used abbreviations: Micro-LED, mLED or µLED). MicroLED was first introduced by researchers in 2000. Like OLED, mLED can score with absolutely excellent black and contrast values. In addition, µLED is very durable and energy-efficient, which is particularly interesting in professional scenarios (operating and running times, maintenance and electricity costs). In contrast to OLED, MicroLED is based on GaN, i.e. an LED technology. Compared to OLED, mLED supporters point to a longer lifespan and the high luminance of the self-illuminating LEDs.

At the current CES 2018, Samsung has now presented a consumer product - presumably in the high-end price segment - which shows once again that at least the large Korean manufacturer MicroLED considers one of the future technologies - for screens in all possible sizes and B2C and B2B applications: "The Wall", a 146 "mLED TV, the world's first modular in this class. The advantage is obvious: As with LED walls, modules can be built or personalized in modules of any size, in a very shape-free manner.

In recent years, Chinese manufacturers have also presented the first TVs with LED modules as a proof-of-concept, but mostly only on the domestic market. The world's first micro LED TV is the prototype of a 55 "Full HD" Crystal TV "that Sony launched in 2012. It is considered the ancestor of the CLEDIS (canvas display). The self-emitting technology CLEDIS uses ultra-fine LEDs with R (red ), G (green) and B (blue) on the display surface. Each pixel consists of a separate ultra-fine R, G and B LED and the light source is only 0.003 mm2. The remaining area is more than 99% black .

For business-to-business applications, both Samsung and other players such as Sony have launched the first products that use MicroLED architectures: Sony has its CLEDIS solution, Samsung has the cinema LED screen. Both groups rely on extremely small, self-illuminating LEDs. While CLEDIS was already convincing in effect at ISE 2017, other manufacturers could also show new MicroLED products at the trade fair in February 2018. Samsung is at least a candidate for this - but is currently not commenting on the topic.

Should, would have, supply chain: There is more than one indication from the supply chain of the display industry that µLED could still be used in specific digital signage products this year - of course no guarantee, but strong evidence. Because the 146 "MicroLED TV from Samsung now shown was expected according to market rumors from autumn 2017, but as a 150" TV.

For the first time in May 2017 and then in autumn 2017, there were market rumors that Samsung would buy or participate in the Taiwanese mLED specialist PlayNitride Inc. founded in 2014. While PlayNitride denied this, Samsung did not comment on the reports. At the end of 2017, PlayNitrides said that there were purchase offers from several companies. So far, LED expert Epistar and the Taiwanese semiconductor manufacturer United Microelectronics Corporation (UMC) have been the only known shareholders of PlayNitride.

But even without a purchase, Samsung relies on µLED: In-house developments and possible licensing make this possible. As can be seen in the case of the LED cinema screen, the group has already launched a product ready for series production - and into the real world of project installations.

The usually more than well-informed industry service Digitimes recently reported about another manufacturer that has specific MicroLED products in the pipeline, the South Korean manufacturer Lumens (not to be confused with the Taiwanese manufacturer Lumens of similar name, who will be among the exhibitors at ISE 2018 becomes).

According to the Digitimes report, industry sources speak of the development of 0.57 "MicroLED screens up to a 100" digital signage screen that should use 100 to 300 micron "large" µLED modules.

Whether at the ISE or at the InfoComm or one of the major Asian trade fairs: One should not be too surprised when the first large display manufacturer presents a MicroLED digital signage screen this year - for example in the class of 98 "large format displays.

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 466000 [0449]
• DE 229408 [0683]

Non-patent literature cited

• DIN EN 8942-2 ^[1] [0228]
• DIN standard 44300 [0366]

Claims (52)

Electrically controlled display element for optical signaling of variable information such as characters or images with an integrated electronic element with processor and memory function, characterized in that the control takes place via a wireless connection from an external computer / computer and the display element has a thickness of 0.3 up to 4.5 mm, the electronic element having a maximum thickness of 1 mm. Display element after Claim 1 , characterized in that the electronic element consists of at least one hardware element and / or software and / or APP application. Display element after Claim 1 , characterized in that the electronic element consists of an exchangeable physical chip card and / or a built-in physically non-exchangeable chip card and / or an element having a function identical to a chip card. Display element after Claim 1 , characterized in that the electronic element has an identification and / or authentication function of a user in a digital network. Display element after Claim 1 , characterized in that the wireless connection consists of a radio and / or light (LiFi) and / or ultrasound network. Display element after Claim 1 , characterized in that the wireless connection, preferably via a radio connection based on a G-frequency radio connection, preferably based on 3G and / or 4 G and / or 5G and / or a mobile radio connection and / or based on a Bluetooth, and / or WLAN, and / or WIFI and / or LiFi and / or satellite connection (GPS) exists. Display element after Claim 6 , characterized in that the channel bandwidth of the radio connection is in the range of 100 MHz to 100 GHz, preferably 800 MHz to 30 GHz, in particular 3 GHz to 6 GHz. Display element after Claim 1 , characterized in that the electronic element preferably has a maximum format of 85.6 mm x 54 mm, in particular a format of 25 mm x 15 mm and / or 15 mm x 12 mm and / or 12.3 mm x 8.8 mm having. Display element after Claim 1 , characterized in that the electronic element, preferably has a maximum thickness of 1 mm, preferably a thickness of at least 0.3-1 mm, in particular 0.76 mm and / or 0.67 mm. Display element after Claim 1 , characterized in that the electronic element, preferably has a storage capacity of at least 128 gigabytes. Display element according to one of the preceding claims, characterized in that the display element and / or hardware element at least one camera and / or video camera and / or scan function and / or sensor function and / or infrared light function and / or speaker function and / or microphone function and / or sound card having. Display element according to one of the preceding claims, characterized in that the sensor function detects physical, chemical and material properties quantitatively or qualitatively, preferably with a measuring function for temperature, amount of heat, moisture, pressure, weight, distance measurement, rain sensor, sound, brightness, acceleration, PH Value, ionic strength, electrochemical potential and / or the material properties are recorded qualitatively. Display element according to one of the preceding claims, characterized in that the electronic element has a digital link to an IT infrastructure via a computer network. Display element according to one of the preceding claims, characterized in that the IT infrastructure has an encrypted accounting system and / or method. Display element according to one of the preceding claims, characterized in that the electronic element has at least one encryption code and / or is digitally linked to at least one encryption code. Display element according to one of the preceding claims, characterized in that the encryption code consists of at least eight characters, based on a character space of at least 89 characters. Display element according to one of the preceding claims, characterized in that the encryption code is stored in the IT infrastructure. Use of a display element after Claim 1 for use as a device and / or component element. Use of a display element after Claim 17 , preferably for an element for use as a packaging, vehicle identification, traffic sign, advertising sign, jewelry watch, clothing, accessories, picture frame, floor, wall, ceiling, furniture -, Decoration, interior design element, preferably strip, profile, edge, door and / or window element, facade, wallpaper, car interior, car exterior, household appliances, electrical appliances, and / or Outdoor covering element. Use of a display element after Claim 1 , preferably for an element as an official identifier for a vehicle, preferably for a car, truck, omnibus, two-wheeler, motorcycle, e-bike, e-scooter, caravan, commercial vehicle, trailer, tram, train, aircraft, in particular an aircraft, a helicopter and a ship. Display element after Claim 1 , characterized in that the electrically controlled display consists of a screen and / or screen and / or display, in particular a smart display, and / or monitor and / or touchscreen surface or a projected surface. Display element after Claim 1 , characterized in that the display technology of the electrically controlled display is preferably based on technology from light emitting diodes (LED) field emission screens (FED) and / or liquid crystal screen (LCD) and / or thin film transistor screen (TFT-LCD) and / or cathode ray tube screen (CRT) and / or plasma screen and / or organic light emitting diode (OLED), SOLED or SMOLED film displays, PLED, AMOLED- (active matrix OLED) or Super AMOLED +, and / or surface conduction electron emitter display (SED) and (or QLED and / or Micro LED (microscopic light-emitting diodes and / or HDR (High Dynamic Range) and / or electronic ink and / or e-paper is generated. Display element after Claim 1 , characterized in that the display technology of the electrically controlled display preferably on a technological basis of micro LED pixels, preferably with a resolution of at least 7680 x4320 pixels. and / or and / or electronic ink is generated, Display element after Claim 1 , characterized in that preferably a film display based on a film, in particular based on petrochemical and / or biopolymeric plastics and / or organic substances is used. Display element after Claim 23 , characterized in that the film has a thickness of preferably 20 to 1000 microns, in particular 20 to 100 microns Display element after Claim 23 , wherein the film has printed electronics. Display element according to one of the preceding claims, characterized in that the power supply, preferably wireless and / or wired on a technical basis, a connection to the power grid and / or an accumulator and / or induction current and / or by radio current and / or by ultrasound transmission, preferably with Piezo technology based sensors is generated. Display element according to one of the preceding claims, characterized in that the accumulator has a maximum thickness of 0.3 to 4.5 mm. Display element according to one of the preceding claims, characterized in that the display element can have three-dimensional deformations, and in particular can be rolled and / or folded. Display element according to one of the preceding claims, characterized in that the display element is designed on the basis of geometric and / free shapes, preferably from rectangle, square, circle, ellipse, triangle, polygon, parabola, free-form elements and their Possible combinations. Display element according to one of the preceding claims, characterized in that the display element is integrated into the vehicle body, in particular is formed flush with the body shell. Use of an electronic element with processor and memory function for use as a computer and / or computer element with identification and / or authentication function of a user in a digital network, characterized in that the electronic element consists of at least one hardware element and / or software. Use after Claim 1 , characterized in that the computer and / or computer element is designed as a hardware element, in particular as memory, USB, hard drives, router, smartphone, PDA, tablet, PC, server, game console, netbook , Notebook, mainframe, supercomputer, screen, camera, scanner, display, device and / or component element. Use after Claim 1 , characterized in that the digital network consists of a cable and / or radio network and / or ultrasound network. Use according to one of the preceding claims, characterized in that the electronic element has a digital link to an IT infrastructure via a computer network. Use according to one of the preceding claims, characterized in that the IT infrastructure has an encrypted accounting system and / or method. Use after Claim 1 , characterized in that the software has an application for image recognition, in particular iris recognition. Use after Claim 1 , characterized in that the hardware element has at least one camera and / or scan function or is connected to a camera and / or scan function. Use according to one of the preceding claims, characterized in that the hardware element has an infrared light function and / or is connected to an infrared light function. Use after Claim 1 , characterized in that the electronic element consists of an exchangeable physical chip card and / or a built-in physically non-exchangeable chip card and / or an element having a function identical to a chip card. Use according to one of the preceding claims, characterized in that the electronic element has at least one encryption code and / or is digitally linked to at least one encryption code. Use according to one of the preceding claims, characterized in that the encryption code consists of at least eight characters, based on a character space of at least 89 characters. Use according to one of the preceding claims, characterized in that the encryption code is stored in the IT infrastructure. Use according to one of the preceding claims, characterized in that an image scan, in particular an iris scan, is used for authentication and identification in the IT infrastructure. Use according to one of the preceding claims, characterized in that the image scan in the IT infrastructure is linked to the encryption code. Use according to one of the preceding claims, characterized in that the digital image data have a time stamp accurate to the second for identification and authentication. Use according to one of the preceding claims, characterized in that generated digital data of the electronic element are stored in the IT infrastructure without having to be installed on a local computer Method according to one of the preceding claims, characterized in that the digital image data, in particular the iris scan, for identification and authentication in the IT infrastructure are compared with the digital master image data by means of image recognition software. Method according to one of the preceding claims, characterized in that Method according to one of the preceding claims, characterized in that an automatic digital linkage of the electronic element with the IT infrastructure is established for the identification and authentication of the image scan. Use after Claim 1 , characterized in that the electronic element preferably has a maximum format of 85.6 mm x 54 mm, in particular a format of 25 mm x 15 mm and / or 15 mm x 12 mm and / or 12.3 mm x 8.8 mm having. Use after Claim 1 , characterized in that the electronic element, preferably has a thickness of at most 2 mm, preferably a thickness of at least 0.3 - 1 mm, in particular 0.76 mm and / or is 0.67 mm. Use after Claim 1 , characterized in that the electronic element, preferably has a storage capacity of at least 128 gigabytes.

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