EP1461902A2 - Systeme de communication multicast - Google Patents
Systeme de communication multicastInfo
- Publication number
- EP1461902A2 EP1461902A2 EP02805792A EP02805792A EP1461902A2 EP 1461902 A2 EP1461902 A2 EP 1461902A2 EP 02805792 A EP02805792 A EP 02805792A EP 02805792 A EP02805792 A EP 02805792A EP 1461902 A2 EP1461902 A2 EP 1461902A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- address
- network
- data
- terminal
- multicast
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000004891 communication Methods 0.000 title claims abstract description 32
- 230000005540 biological transmission Effects 0.000 claims abstract description 19
- 238000001914 filtration Methods 0.000 description 14
- 238000012360 testing method Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000002457 bidirectional effect Effects 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 239000004020 conductor Substances 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000005236 sound signal Effects 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000003999 initiator Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/02—Details
- H04L12/16—Arrangements for providing special services to substations
- H04L12/18—Arrangements for providing special services to substations for broadcast or conference, e.g. multicast
- H04L12/189—Arrangements for providing special services to substations for broadcast or conference, e.g. multicast in combination with wireless systems
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L12/407—Bus networks with decentralised control
- H04L12/413—Bus networks with decentralised control with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L45/00—Routing or path finding of packets in data switching networks
- H04L45/74—Address processing for routing
- H04L45/742—Route cache; Operation thereof
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L2012/40267—Bus for use in transportation systems
- H04L2012/4028—Bus for use in transportation systems the transportation system being an aircraft
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L2101/00—Indexing scheme associated with group H04L61/00
- H04L2101/60—Types of network addresses
- H04L2101/618—Details of network addresses
- H04L2101/622—Layer-2 addresses, e.g. medium access control [MAC] addresses
Definitions
- Secure communications system comprising a local area network, for example of the Ethernet type, in particular on board an aircraft
- the present invention relates to a secure communications system comprising a local area network, for example of the Ethernet type. It applies in particular to multifunctional communication systems where it is necessary to ensure a high level of security in the transmission of voice or data, as is the case for example for certain systems on board aircraft.
- An object of the invention is in particular to allow reliable transmission of data within a local communication network.
- the invention relates to a communication system, comprising at least one local network and terminals connected to this network and exchanging data packets.
- Each terminal includes a table memorizing the addresses of the groups of terminals with which it can enter into communication.
- a terminal which transmits a data packet on the network in multicast mode creates a multicast network address whose bits, for example the most significant bytes, have a given value and which comprises the address of the group receiving the data packet, each terminal comparing the address of the recipient group with the content of its table once the network address has been sent on the network.
- FIG. 2 a block diagram of a system according to the invention
- FIG. 3 an illustration of the software layers of a receiving terminal involved in the filtering of data transmitted in the system
- FIG. 4 an illustration of the addressing mode of data packets used by a transmitting terminal
- FIG. 5 an illustration of the analysis of the addresses of transmitted packets carried out by a receiving terminal
- Figure 1 shows a block diagram of a system 1 according to the invention. It allows several operators to communicate, in particular according to several security levels and to exchange several types of information, voice or not. These operators are for example the crew members of an airplane.
- This system 1 links together several radiocommunication elements Rj, Rj, 2. These elements are for example stations such as radio receivers and radio transmitters, or are for example sets 2 of headphones / microphones integrated in particular in headsets .
- the system 1 can also connect, for example, these elements to recording means 3, to data processing means 4, to control means 5, in particular for maintenance. It also makes it possible to connect to all of these elements KY encryption means so as to protect certain sensitive data, this data representing a voice or any other information, digital or not, during communications or exchanges of information.
- the system 1 notably comprises a local area network 21, for example of the high-speed LAN type, the nodes of which comprise transmission / reception units which are connected to these elements Rj, KY, 2, 3, 4, 5 directly or by interface intermediaries.
- These units include means such as, for example, addressing and communication protocols which allow the routing of data from one group of elements to another group of elements.
- FIG. 2 illustrates by a block diagram the preceding system 1, the latter being for example a multifunctional communication system between several operators.
- the system comprises at least multichannel terminals MCTU and single-channel terminals SCTU located at the nodes of the network 21. It also comprises command and control interfaces 6. These interfaces 6 can be more or less elaborate.
- the MCTU units are connected to radio stations Ri,... RN, to encryption means KY, as well as for example to maintenance means not shown.
- a multi-channel terminal MCTU can be connected to several elements of the radio station type or encryption means for example.
- the SCTU units are connected to the command and control interfaces 6.
- a SCTU unit and an interface 6 can for example be grouped in the same box.
- the SCTU units are also, for example, connected to headphones and microphones, or any other means of audio or even visual communication.
- a command and control interface 6 is an elaborate man-machine interface, for example a control panel comprising a touch screen and various keys, which allows an operator to select his communication channels.
- the interface 6 therefore links the MCTU and SCTU units to audio communication means of the microphone or headset type, but also to control means of the aforementioned key or touch screen type. It is therefore for example coupled to a control station.
- the system 1 can also communicate with simplified interfaces CB.
- Such an interface CB is for example a basic man-machine interface intended for an operator, this interface is connected directly to an MCTU. It has an audio interface which can be either a headset or a microphone, or any other means of communication.
- a CB interface accesses the system through its own communication channel connected to an MCTU unit. In particular, it does not access an MCTU unit via the local network 21.
- a multichannel terminal unit MCTU is therefore interfaced with a certain number of analog and digital channels connected in particular to the radio sets Rj and to the encryption means KY.
- An analog channel hereinafter called the audio channel, consists of a bidirectional line and a certain number of discrete inputs / outputs providing monitoring of transmissions and receptions. The channel is also called “full duplex" in Anglo-Saxon literature insofar as communications can be done simultaneously in one direction and the other.
- a digital channel hereinafter called the data channel, consists of a bidirectional line, of the "full duplex" type with discrete inputs / outputs to provide control of transmissions and receptions.
- Each MCTU is thus interfaced with the local network 21 by an appropriate circuit. This circuit is controlled by a software layer.
- each SCTU unit is interfaced with the network 21 by such a circuit. In this way, the local network 21 interconnects all the MCTU and SCTU units. It carries all audio, digital or control data across the entire system.
- An MCTU unit in particular performs analog-to-digital and digital-to-analog conversions for all the audio channels which are interfaces to it. It converts and routes input data from a data channel to the network 21. Vice versa, it converts and routes data from the network to the data channels. All incoming data in an MCTU, audio or digital unit, but also addresses are for example automatically assigned a tag according to their security level. In this way, a piece of data can be recognized in a secure manner and used by an appropriate receiver of the network 21. In particular, two security levels are to be considered, a so-called red level and a so-called black level.
- red If the security level of a signal, a digital voice or data, is red, this signal will be assigned a first type of tag, called red. If the security level of a signal, a digital voice or data, is black, this signal will be assigned a second type of tag, called black. Note that the assignment of tags is not limited to red or black tags, but can also be extended to other security levels.
- a single channel SCTU terminal unit constitutes in particular an input or output node of the local network 21 for the audio signals, representing in particular the voices of the different operators. It therefore forms an audio input / output for the system 1.
- a SCTU unit thus comprises, via a control interface 6, a connection with an audio interface which may for example be an audio headset, a microphone or an oxygen mask.
- the SCTU unit comprises, for example, a second channel intended for an observer. This second channel is not a separate data channel, but results from an analog multiplexing before digitization of the signals.
- an analog channel hereinafter called the audio channel, consists of a bidirectional line of “full duplex” type and a certain number of discrete or non-discrete inputs / outputs providing control of transmissions and receptions.
- the control information is notably provided by the associated interface 6. This information depends for example on the level of security requested and the recipients or senders of the messages.
- an SCTU unit is directly interfaced with the local network 21 via an appropriate circuit. In particular, it performs analog-to-digital and digital-to-analog conversions. It assigns its incoming data with a tag corresponding to their security level.
- a SCTU unit is connected to a control interface 6 by a serial bus. This bus is only used for the transfer of control information, that is to say for the control and analysis of the commands sent to the interface 6 or coming from the latter. It does not contain voice information.
- the SCTU unit transfers in particular the data from the interface 6 to the local network 21.
- Each node of the system is physically connected to the local network 21 by a digital integrated circuit known elsewhere, for example with a microprocessor.
- This circuit includes the inputs and outputs necessary for the data conveyed as well as various control information, including the hardware addressing of the circuit.
- the latter is for example connected to the network by means of a number of pairs of conductors, ie four conductors per connection, two of type RX and two of type TX. Other modes of connection to the network are of course possible.
- One of the nodes of the system plays the role of server, in particular for starting up the system. Any MCTU or SCTU can play this role.
- This server contains the system database. When the server is started, it updates the system database in all nodes on the network, that is, in all MCTU and SCTU units. Each node thus has the same database and thus has access to the operational configuration of the entire network.
- the system database makes it possible to identify the authorized operations for each station, for example the communication channels that an operator can select through his command and control interface 6. When the operator makes a selection and presses for example a transmission control button, the audio message is sampled, that is to say that it undergoes an analog-digital conversion by the SCTU unit connected to the interface 6.
- the audio packet thus defined is then picked up by the other nodes MCTU, SCTU of the network which are authorized to do so. So for example, if a user wants to speak to two radios R i? Rk at the same time, each ⁇ t its station sends two successive digital audio signal packets over the network, one packet for the radio station Rj and one for the radio station Rk.
- the header of a packet determines who is authorized to receive it, i.e. it includes the address of the recipient (s).
- the system uses for example the protocols TCP / IP and UDP / IP to communicate in the local network 21.
- the protocol used has a structure in stacked layers where each layer provides a service to the layer which is immediately below it. A packet which is physically received by a unit must then pass through each layer before being presented to the application which resides on the upper layer of the stack.
- Each layer performs a filtering of the received packet so that the unauthorized packets are rejected as soon as possible. This is especially necessary for security reasons.
- an address table is implemented in each MCTU terminal, SCTU.
- Ethernet local area network for example uses six address bytes at the level equipment.
- IP Internet Protocol
- the Internet Protocol (IP) layer above the hardware interface layer uses four address bytes.
- the TCP and UDP protocols use, for example, port numbers to address a given process.
- not all transmitted data can go to any receiver.
- red type data and black type data other security levels which can of course be managed by a system according to the invention. In the configuration example in Figure 2, some data must be encrypted before transmission to radio sets.
- dedicated MCTU units are connected to KY encryption means, these are intended to route the red data which must be encrypted before transmission to radio stations for example.
- Other MCTU units are connected directly to the radios and are intended to route black data which does not require encryption.
- An MCTU is either red or black in time. On the contrary, an SCTU can be red at one time and black at another time.
- the encryption means KY are moreover connected to communication elements to the outside via an MCTU unit, that is to say directly connected to communication elements not shown.
- FIG. 3 illustrates how the filtering of data is applied at the level of each host component 31, each time a frame or packet passes over the local network 21.
- This component 31 is for example an MCTU unit or an SCTU unit.
- the first filtering layer is carried out by the hardware circuit 32 associated with each unit, that is to say the circuit 32 directly connected to the local network 21.
- This connection circuit 32 can be called subsequently the Ethernet circuit to facilitate the description. Any other circuit 32 which is a network hardware interface can of course be used.
- This circuit 32 includes a first software layer 33. Therefore, in a first step, the Ethernet circuit 32 analyzes the address of each packet which passes over the network. In particular, it acts differently depending on whether the data packet is of the unicast or multicast type.
- FIG. 3 illustrates how the filtering of data is applied at the level of each host component 31, each time a frame or packet passes over the local network 21.
- This component 31 is for example an MCTU unit or an SCTU unit.
- the first filtering layer is carried out by the
- a multicast transmission allows the transmission of a data packet from a network node, in this case an MCTU or SCTU unit, to a group of network nodes, that is to say to a set of MCTU units or SCTU.
- Each multicast group is identified by a specific address. Membership in a given multicast group is dynamic, that is to say that units can join or leave a group at any time.
- a unit can belong to several groups at the same time. A unit does not need to be a member of a group to send data to members of that group.
- Multicast groups are for example identified by a class D address 41, corresponding to the TCP / IP protocol, that is to say by an address whose four most significant bits are 1110, forming the value E in hexadecimal. This address is coded on 32 bits. In standard Internet notation, the addresses of multicast groups therefore occupy the space between 224.0.0.0. and 239,255,255,255. The address 224.0.0.0. for example, is not used and the address 224.0.0.1. is for example reserved for the multicast group corresponding to all the MCTU and SCTU units.
- the addresses of the multicast groups are stored in a table 42, hereinafter called the multicast table. This table 42 is present in each MCTU, SCTU, more particularly in its associated Ethernet circuit 32.
- An MCTU, SCTU is connected to the local network 21 via this circuit.
- the multicast table stored in a unit, or more particularly in its connection circuit 32 represents all of the multicast groups to which this unit belongs. Each multicast group therefore corresponds to an address, and to this address corresponds a channel.
- a channel is in fact a virtual connection which exists between an initiator of the channel, typically the operator activating its command and control interface 6, and one or more stations.
- a channel is identified by a unique number so that it can be used within the local network 21 without ambiguity. So for example, when an operator activates its control and command 6 to enter into communication with a group of interlocutors, this interface 6 sends a message to its associated SCTU unit indicating the chosen channel number corresponding to the selected group. The channel number corresponds for example to the location of the multicast group address in table 42.
- the SCTU unit will therefore look in its multicast table 42 for the corresponding multicast group address and then create the multicast network address of the data packet which will be transmitted, this network address 43 being for example coded on 48 bits, like the illustrates FIG. 4.
- this network address 43 being for example coded on 48 bits, like the illustrates FIG. 4.
- the 23 least significant bits of the multicast group address 41 form the 23 least significant bits of the network address 43.
- the next bit is for example not used, and fixed arbitrarily 0 in the network address.
- the three most significant bytes of the network address 43 are always set to the same value, for example an Ethernet address value coded in hexadecimal base 01 00 5E. A network address starting with this value 01 00 5E will be understood as a multicast Ethernet address.
- the five bits of the multicast group address 41 comprised between the 23 least significant bits and the four most significant bits forming the hexadecimal value E are not used, and therefore not carried over to the network address. For example, if a multicast group address has the value E1 55 55 55, its corresponding data will be transmitted with the network address 01 00 5E 55 55 55.
- the address transferred was of the IP (Internet Protocol) type, in particular TCP / IP. Other types of protocols can of course be considered.
- this address was transferred on 23 bits. It can obviously be transferred to another number N of bits, in particular as a function of the structure of the network and of the reception circuits.
- connection circuit 32 Consequently, the analysis of the addresses carried out by the connection circuit 32 is done in accordance with FIG. 5. It is assumed that an SCTU unit sends a packet with a destination address.
- the Ethernet circuits 32 of the other units analyze this address as illustrated in FIG. 5. On Ethernet for example, the least significant bit of the most significant byte of the multicast address is set to 1. Thus, in hexadecimal base , this address is of type X1: XX: XX: XX: XX.
- the circuit 32 having checked that it is an Ethernet address, it checks in a first test 51 that the network address 43 contains a multicast address 41 of class D, that is to say in accordance with the creation addresses previously described, let this network address start with the value 01 00 5E.
- the circuit 32 will check by a following test 54 if it belongs to the multicast group receiving the message. For this, it reconstitutes the multicast address by the opposite operation to that illustrated in FIG. 4, in particular by extracting the 23 least significant bits. Then it verifies that the multicast address thus obtained is contained in its multicast table 42.
- the message belongs to the recipient multicast group and the message is then processed by the following software layer 34.
- This address will then be processed conventionally as a multicast address in the communication protocol which is for example of the TCP / IP or UDP / IP type. If the multicast address is not contained in the multicast table of circuit 32, the latter rejects the message 53.
- the Ethernet circuit 32 receives only the packets whose destination address corresponds either to its hardware address, or to a multicast group address contained in its table 42.
- This circuit is controlled by a software layer 33 which is the first of the stack of successive software layers which will filter the messages received.
- This first software layer 33 transmits the packets to the next layer 34 which is for example an IP layer.
- This Internet IP protocol performs filtering based on the source and destination addresses, and transmits the datagram to the next layer 35, which is a TCP / IP or UDP / IP layer, if all is compliant.
- this last layer 35 receives a datagram from the IP layer 34, it performs a filtering based on the number of the destination port, and possibly also on the source port number. So there is here an additional filtering level which takes into account the port number of the transmission source.
- a system according to the invention is implemented so that each channel has a unique multicast address, and also, for example, so that each source unit, in particular the SCTU units, has a unique port number. This allows a receiving unit, at its last level software layer 35 for example, to distinguish for each channel the different sources. For a given channel, that is to say for a given multicast address, and a given source port number N1, N2, N3, ... the software layer 35 of a receiving unit can thus activate a corresponding application 36 , 37, 38. Each channel - port number pair can therefore correspond to a specific treatment.
- Another level of security can be based on the type of information transmitted. As previously mentioned, this level of security can be based on the red or black classification of the data. To this end, each packet sent includes a tag whose value indicates whether the data transmitted is red or black. This tag does not necessarily give binary information, in particular it can affect data sent from information other than the red or black type. This tag is generated by the transmitting unit. The analysis of the tag is notably executed by the software layers of the receiving unit. Thus, if an MCTU receives a red message while it is classified black, it will reject the message.
- FIG. 6 illustrates an example of a data packet structure 61 generated by an SCTU in a system according to the invention.
- This packet includes in the header the network address 43, the port number 62 of the sending unit, of the tag 63 and of the message 64.
- the address 43 is of the multicast type in the case of multicast transmission, it is therefore for example equal to 01 00 5E XX XX XX.
- the port number 62 is coded on a number of bits compatible with the number of source units in play.
- the tag is coded on a given number of bits, for example 8 bits. Even if it only defines a binary state, for example the red or black qualification of messages, it is more reliable that it is coded on a number of bits greater than one.
- FIG. 7 illustrates an example of classification of multicast group addresses in the multicast table 42 for filtering purposes, allowing in particular a strengthening of the filtering of the transmitted data. Since transmission security is important, it is advantageous to use several successive tests as has just been described. An additional test can be carried out on the place of the multicast addresses in the multicast table 42 associated with each unit. This security level is here based on the place of the multicast addresses in this table 42 as described in FIG. 7. In other words, the channels are classified into categories, the position of the multicast address of a channel in the table 42 being a function of its category.
- FIG. 7 illustrates a storage of the multicast addresses in the table 42 according to their category.
- the addresses of the first category occupy for example the N first boxes of the table
- the addresses of the second category occupy the M following boxes and so on.
- a space of several unoccupied boxes can be left between two categories of addresses.
- the red multicast addresses occupy for example the first N boxes
- the black multicast addresses occupy for example the following boxes.
- a filtering can be done based on this arrangement.
- a black receiving unit which receives a multicast address stored in the red zone of the table will reject the information.
- the receiving unit is an MCTU unit
- this application corresponds by transmitting data to encryption means if the MCTU unit is red or by digital-analog conversion of the signal and transmitting it to a radio station if the MCTU unit is black.
- alarms can be generated in the event that non-conforming data crosses a first security level, typically red data received by a black unit.
- a system according to the invention can be embarked on an airplane or a ship for example.
- it allows all crew members to communicate with each other and with the outside in accordance with several levels of security.
- the information exchanged is in this case voice messages but this information can in fact represent many other types of data.
- This data could for example be video data, written messages, figures, computer processing, etc.
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Small-Scale Networks (AREA)
- Data Exchanges In Wide-Area Networks (AREA)
Abstract
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BE2001/0837A BE1014777A3 (fr) | 2001-12-21 | 2001-12-21 | Systeme de communications securisees, comportant un reseau local par exemple du type ethernet, notamment embarque dans un aeronef. |
BE200100837 | 2001-12-21 | ||
PCT/FR2002/004258 WO2003056754A2 (fr) | 2001-12-21 | 2002-12-10 | Systeme de communication multicast |
Publications (1)
Publication Number | Publication Date |
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EP1461902A2 true EP1461902A2 (fr) | 2004-09-29 |
Family
ID=3897154
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP02805792A Withdrawn EP1461902A2 (fr) | 2001-12-21 | 2002-12-10 | Systeme de communication multicast |
Country Status (5)
Country | Link |
---|---|
US (1) | US20050105527A1 (fr) |
EP (1) | EP1461902A2 (fr) |
AU (1) | AU2002364636A1 (fr) |
BE (1) | BE1014777A3 (fr) |
WO (1) | WO2003056754A2 (fr) |
Cited By (2)
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USH1511H (en) * | 1992-09-10 | 1995-12-05 | Chappell; Charles W. | Absorbent articles having improved longitudinal fluid movement |
CN102801622A (zh) * | 2012-08-14 | 2012-11-28 | 神州数码网络(北京)有限公司 | 一种数据报文的转发方法及转发装置 |
Families Citing this family (7)
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FR2936071B1 (fr) * | 2008-09-15 | 2010-10-29 | Airbus France | Procede et dispositif pour automatiser des procedures de verification d'equipements dans un aeronef. |
WO2010070459A1 (fr) * | 2008-12-16 | 2010-06-24 | Acceleradio Ltd. | Système et procédé d'exploitation d'un dispositif de relais |
US8275494B1 (en) | 2009-12-31 | 2012-09-25 | Michael Roth | System, apparatus and method for controlling an aircraft |
FR2989854B1 (fr) * | 2012-04-23 | 2014-05-09 | Team | Commutateur pour relier selectivement un recepteur a l'une de deux sources de signaux, et centrale de gestion de communications comportant un tel commutateur |
US10321310B1 (en) * | 2013-06-04 | 2019-06-11 | Rockwell Collins, Inc. | Secure authentication of mobile devices using sensor transfer of keying material |
CN103491129B (zh) * | 2013-07-05 | 2017-07-14 | 华为技术有限公司 | 一种业务节点配置方法、业务节点池注册器及系统 |
US9522744B2 (en) * | 2014-09-05 | 2016-12-20 | Ge Aviation Systems Llc | Method for management of a maintenance routine for an aircraft and a maintenance system |
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US5579480A (en) * | 1995-04-28 | 1996-11-26 | Sun Microsystems, Inc. | System and method for traversing ATM networks based on forward and reverse virtual connection labels |
KR100308112B1 (ko) * | 1997-07-09 | 2001-10-19 | 김영환 | 이더넷 컨트롤러의 어드레스 검출장치 및 검출방법 |
US6839348B2 (en) * | 1999-04-30 | 2005-01-04 | Cisco Technology, Inc. | System and method for distributing multicasts in virtual local area networks |
US6526058B1 (en) * | 1999-08-18 | 2003-02-25 | Nortel Networks Limited | VODSL service provision |
US6975628B2 (en) * | 2000-12-22 | 2005-12-13 | Intel Corporation | Method for representing and controlling packet data flow through packet forwarding hardware |
US7154859B2 (en) * | 2001-10-24 | 2006-12-26 | The Boeing Company | Method for improving bandwidth performance of a mobile computer network |
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2001
- 2001-12-21 BE BE2001/0837A patent/BE1014777A3/fr not_active IP Right Cessation
-
2002
- 2002-12-10 AU AU2002364636A patent/AU2002364636A1/en not_active Abandoned
- 2002-12-10 WO PCT/FR2002/004258 patent/WO2003056754A2/fr not_active Application Discontinuation
- 2002-12-10 US US10/498,938 patent/US20050105527A1/en not_active Abandoned
- 2002-12-10 EP EP02805792A patent/EP1461902A2/fr not_active Withdrawn
Non-Patent Citations (1)
Title |
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See references of WO03056754A3 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USH1511H (en) * | 1992-09-10 | 1995-12-05 | Chappell; Charles W. | Absorbent articles having improved longitudinal fluid movement |
CN102801622A (zh) * | 2012-08-14 | 2012-11-28 | 神州数码网络(北京)有限公司 | 一种数据报文的转发方法及转发装置 |
CN102801622B (zh) * | 2012-08-14 | 2016-02-24 | 神州数码网络(北京)有限公司 | 一种数据报文的转发方法及转发装置 |
Also Published As
Publication number | Publication date |
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WO2003056754A9 (fr) | 2004-04-15 |
US20050105527A1 (en) | 2005-05-19 |
WO2003056754A2 (fr) | 2003-07-10 |
WO2003056754A3 (fr) | 2004-01-22 |
BE1014777A3 (fr) | 2004-04-06 |
AU2002364636A1 (en) | 2003-07-15 |
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