What is the difference between a port and a socket?

Question

This was a question raised by one of the software engineers in my organisation. I\'m interested in the broadest definition.

Answer 1

Socket is an abstraction provided by kernel to user applications for data I/O. A socket type is defined by the protocol its handling, an IPC communication etc. So if somebody creates a TCP socket he can do manipulations like reading data to socket and writing data to it by simple methods and the lower level protocol handling like TCP conversions and forwarding packets to lower level network protocols is done by the particular socket implementation in the kernel. The advantage is that user need not worry about handling protocol specific nitigrities and should just read and write data to socket like a normal buffer. Same is true in case of IPC, user just reads and writes data to socket and kernel handles all lower level details based on the type of socket created.

Port together with IP is like providing an address to the socket, though its not necessary, but it helps in network communications.