Van Jacobson TCP/IP Header Compression, created by scientist [[Van Jacobson]] and described in [[http://www.ietf.org/rfc/rfc1144.txt RFC 1144]], is a [[data compression]] protocol specifically designed to improve [[TCP]]/[[IP]] performance over slow serial links. Van Jacobson compression reduces the normal 40 [[byte]] TCP/IP packet headers down to 3-4 bytes for the average case. It does this by saving the state of TCP connections at both ends of a link, and only sending the differences in the header fields that change. This makes a very big difference for interactive performance. Van Jacobson Header Compression (also VJ compression, or just Header Compression) is an option in most versions of [[PPP]]. Versions of [[SLIP]] with VJ compression are often called CSLIP (Compressed SLIP).
