What exactly is a computer protocol?

Computer protocol, also known as network protocol, is a set of conventions that two communication computers must abide by together.

In order to make data reach the destination from the source on the network, the participants in network communication must follow the same rules, which are called protocols, and the protocols are finally embodied in the format of data packets transmitted on the network. The most common computer protocol is OSI/RM protocol.

In 1978, the International Organization for Standardization (ISO) put forward "open system interconnect", which is the famous OSI/RM model. It divides the communication protocol of computer network architecture into seven layers, from bottom to top: physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer. Among them, the fourth layer completes data transmission service, and the upper three layers serve users.

Extended data

Common computer protocols include:

1, IPX/SPX protocols

It is a protocol developed by Novell, which is dedicated to NetWare networks, but it is also very common. Most online games support IPX/SPX protocols, such as StarCraft and Counter-Terrorism Elite.

2.ARP/RARP agreement

Address resolution protocol, the principle is that when a host sends information, it broadcasts an ARP request containing the target IP address to all hosts on the network and receives a return message to determine the physical address of the target; After receiving the return message, the IP address and physical address are stored in the local ARP cache for a certain period of time, and the ARP cache is directly queried next time to save resources.

3.TCP/IP agreement

It is the most basic protocol and the foundation of the Internet. It consists of IP protocol in the network layer and TCP protocol in the transport layer. Generally speaking, TCP is responsible for finding transmission problems, and immediately sends out signals when problems occur, requesting retransmission until all data are safely and correctly transmitted to the destination. IP is to assign an address to each networked device on the Internet.

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