TCP/IP (Transmission Control Protocol/Internet Protocol) Referring to the ARPA protocol suite that provides the basis for what has evolved into the Internet and, therefore, often is referred to as the Internet protocol suite. This is a four-layer protocol suite that maps into the OSI Reference Model that followed a few years later.Table T-2 includes the major protocols that comprise the TCP/IP protocol suite as they relate to the ARPA and OSI models. |