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This article will explain in detail what kind of network the frame relay network is in the computer network. The editor thinks it is very practical, so I share it for you as a reference. I hope you can get something after reading this article.

Frame Relay network is a kind of wide area network; frame Relay is a kind of bearer service that provides two-way transmission of user information flow between user and network interface, and keeps the information order unchanged; frame Relay network is composed of frame Relay node machine and transmission link; in frame Relay network, it is difficult to connect each frame Relay node machine economically or constructively.

Frame Relay is a kind of bearer service that provides two-way transmission of user information flow between user and network interface and keeps the order of information unchanged. Frame Relay network consists of frame Relay node machine and transmission link. The network provides a connection between two or more user terminals for communication. In the frame relay network, it is difficult to connect each frame relay node machine in terms of economy and construction, so how to build the network reasonably is very important.

Frame Relay (frame relay) is a new public data network communication protocol that emerged in 1992 and has developed rapidly since 1994. Frame Relay is an effective data transmission technology, which can transmit digital information quickly and cheaply in one-to-one or one-to-many applications. It can be used for voice and data communication, not only for local area network (LAN) but also for wide area network (WAN) communication. Each frame Relay user will be given a dedicated line to the frame Relay node. For end users, frame Relay network handles data transmission with other users through a channel that is often changed and invisible to users.

Main features: user information is transmitted in frame, the network checks the frame structure and transmission errors in the transmission process, and discards the error frame directly. At the same time, through the identification of the address segment DLCI in the frame, the statistical reuse of user information is realized.

Frame Relay is a packet-switched communication network, which is commonly used in the data Link layer (Data Link Layer) of the Open Systems Interconnection reference Model (Open System Interconnection). The permanent virtual circuit PVC is used to form an end-to-end logical link on the physical network switched virtual circuit (SVCs). It is similar to the circuit switching in the public switched telephone network, and it is also a part of the frame Relay description, but it is rarely used in practice. In addition, frame Relay was originally designed for the compact format version of the X.25 protocol.

The data link connection identifier DLCI is a local value used to identify each endpoint. Multiple PVC can be connected to the same physical terminal, and PVC generally specifies the committed information rate CIR and the additional information rate EIR.

Frame Relay is designed to make more efficient use of existing physical resources, because the vast majority of customers can not make full use of data services, so it is allowed to provide more data services to customers of telecom operators. It is because telecom operators book too much bandwidth that frame Relay has gained a bad reputation in some markets.

Telecom companies have been selling frame Relay services to customers who are looking for cheaper than dedicated lines, and according to government and telecom policies, it is used in a variety of applications.

Frame Relay is gradually being replaced by ATM, IP and other protocols (including IP virtual private network).

The frame relay network has the following characteristics:

(1) Common channel signaling is adopted. The logical connection that carries the call control signaling is separate from the user data. For example, Ansi T1.603 and ITU-T attachment A both use DLCI=0 as the signaling channel. The reuse and switching of logical connections occur in the second layer, thus reducing the level of processing.

(2) simplify the mechanism. Frame Relay simplifies the x.25 protocol, abolishes the flow control and error control of the second layer, and is only implemented by the end-to-end high-level protocol. The functions of user-network interface and internal network processing are greatly simplified, resulting in low latency and high throughput performance. Frame Relay simply processes the frame and then forwards it. The processing functions include: checking whether the DLCI in the frame header is valid, transmitting the frame if it is valid, deleting if it is invalid; checking whether the frame is correct, transmitting the frame correctly, and deleting the error. Therefore, it is a kind of transmission loss mechanism which is checked but not corrected.

(3) High speed virtual circuit is adopted. Frame Relay cancels layer 3, transfers multiplexing to layer 2, establishes multiple layer 2 logical channels on a physical connection, and realizes statistical multiplexing and dynamic allocation of bandwidth, thus improving efficiency and throughput and reducing delay.

(4) large frame transmission to adapt to bursts. The frame length of FR is much larger than that of x.25 packet, using large frame transmission and variable frame length, the information length of switching unit (frame) is longer than that of packet switching, up to 1024,4096 bytes, and the reservation frame length is at least 1600 bytes, which is suitable for encapsulating data units of LAN and suitable for transmitting burst services (such as compressed video service, www service, etc.).

(5) hardware forwarding and overspeed transmission. DLCI is a kind of tag, short and fixed length, which is easy to be forwarded by hardware at high speed.

This is the end of the article on "what is the frame Relay Network in the computer Network". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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