IP - internet protocol
RFCs
791 - IP protocol specification

HOWTOs

Software

Articles

Further Information
Protocol numbers - next-level protocols




IP is a network layer protocol. Well-known for carrying TCP packets, there are numerous other higher-level protocols it also services. The best known of these are UDP (used by dns, used by CIPE) and ICMP (used by ping). Others are GRE (used in PPTP), and ESP and AH (used in IPSec).