Summary of TCP and UDP protocols

In network learning, we found that TCP and UDP are always mentioned or discussed. In many tests, this knowledge is also an important test site. Therefore, this article will summarize the two Protocols.

In the TCP/IP protocol family, the transmission control protocol (TCP) and User Datagram Protocol (UDP) run on the transport layer. It uses the services provided by the IP layer to provide end-to-end reliable (TCP) and unreliable (UDP) services.

1 TCP protocol

Transport Control Protocol TCP (Transmission Control Protocol) is the transport layer Protocol in the TCP/IP reference model. It uses the sequence validation and packet re-Transmission mechanism, provides reliable data stream transmission and virtual connection services for applications.

Combined with the IP protocol, TCP forms the core of the Internet protocol. The TCP Service provides data stream transmission, reliability, effective traffic control, full duplex operations, and Multiplexing technologies.

2. UDP protocol

User Datagram Protocol (UDP) is a connectionless transport layer Protocol in the TCP/IP reference model. It provides a simple and unreliable information transmission service for transactions.

UDP is basically an interface between the IP protocol and the upper-layer protocol. The applicable ports of UDP protocol run multiple applications on the same device.

UDP does not provide a reliable mechanism for IP protocol, traffic control, and error recovery. An application that uses UDP must take full responsibility for reliability.

3. Differences Between TCP and UDP protocols

(1) Same. The transfer control protocol and User Datagram Protocol share the following characteristics: they all run on the transport layer, both use services provided by the IP layer, and provide end-to-end services.

(2) Different places. The two are different: TCP provides reliable data transmission services for the application layer, and UDP provides unreliable data transmission services.

4. TCP and UDP ports

TCP and UDP define ports to differentiate multiple targets on a given host. Different ports are opened for different services. TCP and UDP have their own port numbers. They can coexist on one host, but do not interfere with each other.

High-level protocol TCP port description High-level protocol UDP port description FTP-DATA20 File Transfer Protocol Data DOMAIN53 Domain Name Server ftp21-file transfer protocol BOOTPS67 Boot Protocol server TELNET23 remote login protocol BOOTPC68 Boot Protocol client SMTP25 Simple Mail Transfer Protocol TFTP69 simple File Transfer Protocol HTTP80 Hypertext Transfer Protocol SNMP161 Simple Network Management Protocol POP3110 Post Office Protocol SNMP-TRAP162 Simple Network Management Protocol trap.