Transmission Control Protocol/Internet Protocol, the suite of communications protocols used to connect hosts on the Internet. TCP/IP uses several protocols, the two main ones being TCP and IP. TCP/IP is a communication language or protocol of the Internet. It can also be used as a communications protocol in a private network (either an intranet or an extranet).TCP/IP is a two-layer program. The higher layer, Transmission Control Protocol, manages the assembling of a message or file into smaller packets that are transmitted over the Internet and received by a TCP layer and he lower layer, Internet Protocol, handles the address part of each packet so that it gets to the right destination. Each gateway computer on the network checks this address to see where to forward the message

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http://gl.umbc.edu/~jack/ifsm498d/tcpip-intro.html
http://compnetworking.aboutod/tcpip/TCPI...otocol.htm