About UDP protocol

UDP Protocol Introduction UDP transmission is very similar to IP transmission. You can regard UDP as an interface that exposes the IP protocol to the transport layer. UDP also transmits data packets in the form of "Best Effort", so UDP is also unreliable ). So why do we need to add an additional UDP protocol instead of directly using the IP protocol? One important reason is that the IP protocol does not have the port concept. The IP protocol transmits IP addresses to IP addresses, which means a conversation between two computers. However, each computer requires multiple communication channels and assigns them to different processes (. A port represents such a communication channel. UDP implements the port so that data packets can be sent to a port based on the IP address. UDP: it is still not so "reliable". Although the UDP protocol is very simple, it is generated later than the more complex TCP protocol. Early network developers developed the IP protocol and the TCP protocol respectively at the network layer and the transmission layer. All communications must first pass the TCP encapsulation, it is encapsulated by IP (Application Layer-> TCP-> IP ). Developers regard TCP/IP as a set of mutual cooperation. But soon, network developers found that the functions of the IP protocol and the functions of the TCP protocol are independent of each other. For some simple communications, we only need the "Best Effort" type of IP transmission, instead of the complex TCP connection establishment method (especially in the early network environment, if too many TCP connections are established, it will cause a lot of network burden, and UDP can process these simple communications relatively quickly ). The UDP protocol is developed as a slave of the IP protocol on the transport layer ". In this way, network communication can bypass the TCP protocol by encapsulating the application layer-> UDP-> IP address. Because the UDP protocol itself is very simple, in fact, it only serves as a bridge for IP transmission. We will see more comparisons between the TCP protocol and the UDP protocol in the explanation of the TCP protocol. The IP address and its slave UDP data packets are also divided into header and payload. UDP is the transport layer protocol, which means that UDP packets need to be encapsulated by the IP protocol (encapsulation) and then transmitted to the target computer through the IP protocol. Then, the UDP packet is split on the target computer and the information is sent to the cache of the corresponding port.