Socket

Socket

A socket is an endpoint for sending or receiving data across a computer network. Sockets are a fundamental technology for network communication, enabling different processes to communicate with each other, either on the same machine or across different machines.

Types of Sockets

There are several types of sockets, each serving different purposes:

• Stream socket: Provides a reliable, two-way, connection-based byte stream. It uses the Transmission Control Protocol (TCP) for communication.
• Datagram socket: Provides connectionless, unreliable messaging. It uses the User Datagram Protocol (UDP) for communication.
• Raw socket: Allows direct sending and receiving of Internet Protocol (IP) packets without any protocol-specific transport layer formatting.

Socket Programming

Socket programming is the process of using sockets to create network applications. It involves the following steps:

1. **Socket Creation**: Creating a socket using the appropriate system call. 2. **Binding**: Associating the socket with a specific IP address and port number. 3. **Listening**: For server sockets, listening for incoming connections. 4. **Accepting Connections**: Accepting incoming connection requests. 5. **Data Transmission**: Sending and receiving data through the socket. 6. **Closing**: Closing the socket when communication is complete.

Socket API

The Berkeley sockets API is a widely used interface for socket programming. It provides a set of functions for creating and managing sockets, including:

• `socket()`: Creates a new socket.
• `bind()`: Binds a socket to an address and port.
• `listen()`: Listens for incoming connections.
• `accept()`: Accepts an incoming connection.
• `connect()`: Connects a socket to a remote address.
• `send()`: Sends data through a socket.
• `recv()`: Receives data from a socket.
• `close()`: Closes a socket.

Applications

Sockets are used in a variety of applications, including:

• Web servers and web browsers
• Email clients and servers
• File transfer applications
• Remote login services
• Peer-to-peer networks

See Also

• Network socket
• Socket.IO
• Berkeley sockets
• Transmission Control Protocol
• User Datagram Protocol
• Internet Protocol

Related Pages

• Network socket
• Stream socket
• Datagram socket
• Raw socket
• Berkeley sockets
• Transmission Control Protocol
• User Datagram Protocol
• Internet Protocol