What is a network protocol

Network protocol is a collection of rules, standards or conventions established for data exchange in computer networks.

For example, a microcomputer user in the network communicates with a mainframe operator. Since the character sets used by the two data terminals are different, the operator The commands entered do not recognize each other. In order to enable communication, it is stipulated that each terminal must first convert the characters in its own character set into the characters in the standard character set before entering the network for transmission. After reaching the destination terminal, it is then converted into the characters in the terminal's character set. Of course, for incompatible terminals, in addition to changing the character set characters, other characteristics such as display format, line length, number of lines, screen scrolling method, etc. also need to be changed accordingly. (Recommended learning: PHP video tutorial)

Elements

##The network protocol is composed of three elements:

(1) Semantics. Semantics is the interpretation of the meaning of each part of the control information. It specifies what control information needs to be sent, as well as the completed actions and responses.

(2) Grammar. Syntax is the structure and format of user data and control information, as well as the order in which the data appears.

(3) Timing. Chronology is a detailed description of the order in which events occur. (Also known as "synchronization").

People vividly describe these three elements as: semantics represents what to do, syntax represents how to do it, and timing represents the order of doing it.

Commonly used protocols

TCP/IP protocol is undoubtedly the most important of these three protocols. As the basic protocol of the Internet, it would be impossible without it. When surfing the Internet, any operation related to the Internet is inseparable from the TCP/IP protocol. However, the TCP/IP protocol is also the most troublesome to configure among the three major protocols. It is fine to access the Internet from a single computer. However, if you access the Internet through a LAN, you need to set the IP address, gateway, subnet mask, DNS server and other parameters in detail.

Although TCP/IP is currently the most popular network protocol, the communication efficiency of TCP/IP protocol in the local area network is not high. When using it to browse computers in "Network Neighborhood", problems often occur. Normal browsing. Installing the NetBEUI protocol at this time will solve this problem.

NetBEUI is NetBios Enhanced User Interface, or NetBios Enhanced User Interface. It is an enhanced version of the NetBIOS protocol and has been adopted by many operating systems, such as Windows for Workgroup, Win 9x series, Windows NT, etc. The NETBEUI protocol is useful in many situations and is the default protocol for operating systems before WINDOWS98. The NetBEUI protocol is a short and concise broadcast protocol with high communication efficiency. It does not require any settings after installation and is particularly suitable for transmitting data in "Network Neighborhoods". Therefore, it is recommended that in addition to the TCP/IP protocol, computers in small LANs can also be equipped with the NetBEUI protocol. Another thing to note is that if a WINDOWS98 machine with only the TCP/IP protocol installed wants to join the WINNT domain, the NetBEUI protocol must also be installed.

The IPX/SPX protocol is originally a protocol developed by Novell specifically for use in NetWare networks, but it is also very commonly used - most online games support the IPX/SPX protocol, such as StarCraft, Counter-Strike, etc. . Although these games can also be connected through the TCP/IP protocol, it is obviously more troublesome to use the IPX/SPX protocol because no settings are required at all. In addition, the IPX/SPX protocol does not seem to be very useful in non-LAN networks. If you are sure that you will not play games online in a LAN, then this protocol is dispensable.

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