Socket communication is a fundamental networking concept that enables programs to communicate across networks. Think of a socket as an endpoint for communication - like a telephone that allows two parties to talk to each other. When two computers want to exchange data, they each create a socket and establish a connection through the network.
Socket communication typically follows the client-server model. The server creates a socket, binds it to a specific IP address and port number, then listens for incoming connections. The client creates its own socket and connects to the server's address and port. Once the connection is established, both the client and server can send and receive data through their respective sockets.
Each socket is uniquely identified by a combination of IP address and port number. The IP address identifies which computer or machine the socket belongs to, while the port number identifies which specific process or application on that machine. For example, the address 192.168.1.100 colon 8080 means we want to communicate with the application running on port 8080 of the computer with IP address 192.168.1.100.
The socket communication process involves several key steps. First, the server creates a socket and binds it to a specific address and port. Then it listens for incoming connections. Meanwhile, the client creates its own socket and attempts to connect to the server. Once the connection is established, both parties can exchange data by sending and receiving messages through their sockets. Finally, when communication is complete, the connection is closed by either the client or server.
Socket communication is the foundation for virtually all network applications we use daily. Web browsers use sockets to connect to web servers via HTTP or HTTPS protocols. Email systems rely on sockets for SMTP, POP3, and IMAP protocols. File transfer applications use FTP over sockets. Remote access tools like SSH and Telnet depend on socket connections. Online games, chat systems, database connections, and API communications all build upon the fundamental socket communication mechanism.