SE522316C2 - Procedure and system for intermediate storage of information in a communication system - Google Patents

Abstract

Procedure and communications system to buffer information in a communications system, with a system design which is in accordance with, or is similar to, WWW (World Wide Web), at which a proxy server buffers information or files for further distribution to user 1, at which the information is buffered in a structured way on several levels, at which access time is reduced and that double storing of information is avoided. Communications system including computer equipment located at a user's 1, which communicates via his/her computer by an open computer network, and intends to collect information from one or more computers which are connected to the open computer network, at which the information which is collected to the own computer first is buffered in a special computer, or server, at which the buffering is done in a number of in the communications network existing servers, or computers, depending on the type of information which is collected from the open computer network.

Description

anna »10 15 20 25 30 522 316 The protocol used when WWW documents are processed online is called HTTP - Hypertext Transfer Protocol.

The server program that handles document distribution is called httpd - the HTTP daemon, in UNIX languages. The httpd program is constantly listening for HTTP calls from the web, ready to deliver documents to clients. When it receives a request for a document, it checks that the request is legitimate, that the file exists, and then sends the document to the client's IP Number.

The functions of the WWW server can be summarized as follows and shown briefly in Figure 1: 0 Download and return HTML documents to client programs 0 Translate URLs to the server's file system (mapping) I Send information about the file type, date and size according to MIME (typing) 0 Generate and send graphic file directories with README files 0 Send users' HTML pages via / ~ username / 0 Redirect HTTP requests to other WWW servers (redirection) 0 Keep a log file with data about which computers requested which documents 0 Start external programs to retrieve data and generate dynamic documents 0 Include external files in HTML documents (server side includes, end. NCSA) 0 Act as proxy server and cache files. 10 l5 20 25 30 Technical problem.

A WWW server that works as a so-called proxy server (usually) receives HTTP calls from clients on a local network and forwards them to the external final destination. When the documents are then delivered from the network, the proxy server receives the document, stores it in its cache and finally sends it to the client program. This will be done for all HTTP calls for the client programs that have set up the server as their proxy server.

A proxy server is usually operated in a so-called firewall computer that acts as a barrier between a local network and the Internet.

The caching of documents in the server's cache has the good effect that many documents can be retrieved directly from the server's cache without having to load the network outside.

However, this storage methodology is not as well thought out and efficient as the system is only to a limited extent adapted for simpler terminals and smaller bandwidths such as e.g. when transmitting information via modem or ISDN.

Technical solution The technical solution is described in what is stated in the claims.

Benefits.

The present invention improves the communication between a user and the open data network Internet, especially when the transmission takes place via smaller bandwidths such as e.g. when using a modem or ISDN.

By dividing images, web pages into their components (ie text, audio and video) which are then stored on different proxy servers in the system, a better use of 522 316 n o o | v u. u u v. available storage space than with today's proxy system with only one level (equivalent to Access Proxy).

List of figures Fig. 1 shows a known principle solution for WWW.

Fig. 2 shows a part of a network architecture according to the invention. Detailed description.

To facilitate understanding of the present invention, an explanation of abbreviations is used. 15 HTML HyperText Markup Language. The "language" used, and as Netscape interprets, when creating a web page, for layout and links. Almost all web page addresses end in ".html". If you want to see what the HTML code looks like, you take up a web page and select 20 "View Source" or "Document Source" under the "View" -) menu in Netscape, the code will appear. Everything inside the "<" and ">" parentheses are HTML tags.

) HTTP HyperText Transfer Protocol. A transfer protocol used when two computers send hypertext documents (document.html) between them. : anno 3 * \ 30 IP Internet Protocol. One of the protocols eg, the Internet is based on. c Q n 1 Q v o on IP address, IP number A numeric address of a computer on an IP network (eg Internet). IP addresses have the form 5 nnn.nnn.nnn.nnn, ie four groups of one to three integers, separated by dots.

Gif, .gif) Graphical Interchange Format. An image format, or rather a way to compress images. Java) A programming language used to enhance the interactivity of a web page. In practice, it works so that when the user enters a page with Java, the small program is loaded over 15 to his computer, and executed by the browser, so it is run by Netscape.

MIME Multipurpose Internet Mail Extension. A standard for, among other things, sending attachments by e-mail. MIME also makes it possible to send Swedish / national) characters (à, ä, ö) by e-mail without distorting them.

World Wide Web. "The World Wide Web". The Internet server system contains information 25 and services which are linked together by means of hypertext documents. w ...- u. ~ »av» a-Q. .v- s> .. - .. 10 15 20 25 30 522 316 23:11; Figure 2 shows a network architecture for efficient intermediate storage in the World Wide Web according to the invention. The figure shows schematically the division of the intermediate storage into different proxy levels and the name of the different intermediate storage locations (proxy) where intermediate storage takes place and which is described in the following.

The invention is described in an embodiment, where up to three proxy steps exist between client and original web server.

If a user intending to use the Internet uses a limited number of terminals (computers), in most cases Access Proxy and Home Proxy will be the same SerVeI '.

The procedure for caching information is based on users authenticating themselves in order to be offered advanced and individualized services.

At the first level, user authentication and connection to the respective home proxy takes place. This is done through the functionality available in an Access Proxy. This is done either integrated with the IP network authentication (eg in the modem pool) or via a separate JAVA mechanism in Access Proxy.

Once a user has authenticated via login, he / she can use all services and resources to which he / she is authorized. This is ensured by the proxy servers using a common database for user information and logins.

Second-level proxy features ensure a quality level (QOS) that is tailored to the user's system by reducing file sizes to the user's available bandwidth and hardware.

By distributing the files on different servers in a structured way, through the functionality found in vv.- «.- '-.w _ .. u-. nu .. »- .-> uw. ~ ._ 10 15 20 25 30 522 316 .sauc-. 0 o n on.- homeproxy, double storage is avoided. The second level includes Home Proxy, Mime Proxy, Site Proxy and Push Tuner.

Home Proxy is located in a physical server that the system has identified as optimal for a particular user. A user who normally connects from the same geographic location will be assigned by the system to the nearest Home Proxy server. If a user changes their access pattern (eg when traveling or moving permanently), the system will change the assignment of Home Proxy for this user after a certain time. For most accesses, Home Proxy will therefore be the same server as Access Proxy.

Because each user always uses the same Home Proxy, this server's cache will often contain the requested "hit rate" for the cache function in Home web material, i.e.

Proxy gets high.

Home proxy selects for each HTTP access whether the material should or should not be retrieved directly from the original web server, retrieved via specialized MIME Proxy or Site Proxy. way Home Proxy controls the second proxy level. In the same way, designated Site Proxy provides a mechanism for efficiently storing information belonging to popular information providers, without the users having to choose between so-called "mirror sites".

To further save bandwidth, Home Proxy has functionality to compress the information if it knows that the terminal can handle decompression. Similarly, Home Proxy handles the unpacking of compressed information in formats unfamiliar to the terminal.

Certain web material needs to be adapted for different bandwidths, different types of terminals or according to the user's wishes.

Examples of this are graphical material (eg MIME types 1 ad- 10 15 20 25 30 52 2 316 gin: image / gif and image / jpeg), whose bandwidth requirements are greatly reduced by reducing the color and pixel resolution. In the same way, presentation elements such as e.g. video to otherwise insufficient bandwidths and terminals.

Because MIME Proxy specializes in handling specific MIME types, it is equipped with special software or hardware to customize this particular type of information without major delays. Scalability for these MIME types is an important part of offering Custom Quality of Service (QOS).

In the system, all Home Proxy know which MIME Proxy handles each MIME type.

Some sites on the World Wide Web are more popular than others.

Because some proxy servers are responsible for caching information from a specific name domain (eg ibm.com) that is not handled by MIME proxy, such as software or text, better storage efficiency is obtained than if all proxy servers cache this information.

A Home Proxy knows which Site Proxy handles different domain names. Because the system knows which proxy server (s) cache information from a certain name domain, it is possible to make a programmed update of the material, m.h.a. s.k. PUSH technology.

The third level is the public Internet. This level is used if the desired information is not in the system or if an update has been made to the original web server. Owners of popular websites can offer information channels through which updates are sent out regularly (many times a day). This avoids all readers having to go to the original web server to get the most up-to-date information. A s.k. Push Tuner is used to load a Site Proxy with updated information.

The invention is limited only to what is stated in the claims, so the idea of the invention is applicable to all types of intermediate storage methods which are realized in a communication network.

Claims (3)

10 15 20 25 30 522 316 70 Patent claims A method for caching information in a communication system, with a system structure that conforms to or resembles WWW (Word Wide Web), wherein a proxy server caches information or files for further distribution to users (1), characterized in that the information is cached on a structured in several levels whereby access time is reduced and that double storage of information is avoided, that the intermediate storage takes place in 3 levels where the first level handles authentication of users and connection to the intended home proxy and the second level contains proxy functions that ensure a Qos adapted to the user's system by reducing the information to the user's available bandwidth and hardware, the third level being the public Internet, that the home proxy distributes the files or information on different servers, that the information consists of web pages that are divided into their components, ie text, image, audio, and video, that the various components l agras in different proxy servers in the system. 2. Communication system comprising computer equipment located at a user (1) who communicates via his computer with an open data network and intends to retrieve information from one or more computers connected to the open data network, the information retrieved to his own computer first being temporarily stored in a special computer or server, characterized in that the intermediate storage takes place at a number of servers or computers located in the communication network, depending on the type of information retrieved from the open data network, that the information retrieved from the open data network 10 522 316 ff is constituted of web pages that are stored at different intermediate storage locations or proxy servers depending on the type of information the web pages represent, the web pages' information consists of the various components text, image, audio, video. Communication system according to claim 2, characterized in that the intermediate storage servers are located in three levels where the user has only direct contact with a first intermediate storage server on a first level and the server providing information to the user located on a third level has direct contact with all servers at a second level among the cached servers.