TCP (Transmission Control Protocol) is a transport layer protocol widely used in computer networks. It provides reliable, connection-oriented data transmission services and is widely used in the Internet and local area networks. This article will introduce the basic principles and usage of TCP, and provide relevant sample code.
Characteristics and working principles of the TCP protocol
The TCP protocol has the following main features:
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Reliability: TCP ensures reliable transmission of data by using data confirmation, checksum, and retransmission mechanisms. The sender splits the data into small packets and acknowledges them upon receipt by the receiver. If the sender does not receive confirmation within a certain period of time, it will resend the data, thus ensuring the integrity and reliability of the data.
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Connection-oriented: Before data transmission, the sender and receiver need to establish a connection. The connection establishment process includes a three-way handshake, that is, the sender sends a connection request, the receiver replies with a confirmation, and then the sender replies with a confirmation again. The establishment of a connection enables the sender and receiver to communicate with each other and provides reliability of data transmission.
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Congestion control: TCP has a congestion control mechanism to avoid network congestion and improve network performance. Congestion control is achieved by dynamically adjusting the send rate and receive rate to ensure that the data traffic in the network does not exceed the network's carrying capacity.
Here is a simple TCP server and client example written in Python:
TCP server sample code:
import socket
# 创建TCP服务器端套接字
server_socket = socket.socket