TCP - transmission control protocol
RFCs
793 - TCP protocol specification

1122 - TCP additional requirements
 see section 4.2

1323 - TCP extensions for high performance

2001 - slow start, congestion avoidance, fast retransmit, fast recovery

5681 - TCP congestion control

6298 - TCP retransmission timer


HOWTOs

Software

Articles
TCP tutorial

Further Information

TCP is a reliable host-to-host transport protocol. Higher layer (application) protocols it typically carries are http, ftp, telnet, and others. The network layer protocol that typically carries it is IP.