RFC 793, "Transmission Control Protocol", September 1981Source of RFC: Legacy
Area Assignment: tsv
Errata ID: 4753
Reported By: Sanjeev Ranot
Date Reported: 2016-07-30
Rejected by: Mirja Kühlewind
Date Rejected: 2016-09-14
Section 1.5 says:
A pair of sockets uniquely identifies each connection. That is, a socket may be simultaneously used in multiple connections
It should say:
A pair of sockets uniquely identifies each connection. Sockets can be classified into client and server sockets. Typically a server socket may be simultaneously used in multiple connections.
TCP is connection oriented therefore when we say "sockets used in multiple connections" it implies that the context is TCP. Considering their use in TCP, though a single client socket can be implemented in a way to multiplex it for connection with multiple server sockets and exchange different SYN segments but then its same what a server process listening for connections on server port does typically.
I feel classification of sockets here is vital to facilitate understand implicitly that in what use-case can a socket be typically multiplexed while still keeping generality of the statement.
TCP sockets don't have a client/server concept therefore this clarification is inappropriate.