TCP, Transmission Control Protocol, is a networking protocol that enables connections between two machines on a network.

The Original RFCs

Additional RFCs

Historic Extensions

The extensions specified in RFC 1072, RFC 1106, RFC 1110, RFC 1145, RFC 1146, RFC 1379, RFC 1644, and RFC 1693 were all moved to Historic Status by RFC 6247, and some of the RFCs in the section above have older, obsolete versions.

Port Numbers

IANA also maintains the list of assigned TCP and UDP port numbers, such as “Port 80” for HTTP.