What is TCP/IP?

TCP/IP - Is a suite of protocols, and a protocol is a set of rules that govern communication between devices. Released in 1983 by Unix, Transmission Control Protocol / Internet Protocol (TCP/IP) is a suite of related internet protocols developed to allow computers to share the resources across a small network or LAN (Local Area Network), and which connect into a larger hierarchy of networks, otherwise known as a network of autonomous systems, or The Internet.

TCP/IP is a suite of several protocols which handles the movement of data across a physical link and between computers, and is the standard for communicating between two or more computers. Today the current version of IP is IP Version 4 (IPv4), and the next version IPv6 (in use today) will be widely used in years to come. See our pages on ‘Introduction to Subnetting’ for additional information.

TCP is a connection-oriented protocol (ref. OSI Model, Transport Layer) which regulates the flow of information from source to destination reliably and accurately by establishing a virtual circuit between end user applications. QOS describes the purpose of Layer 4, Transport layer. See also UDP for related information.

IP (Internet Protocol) is the primary Layer 3 protocol (ref. OSI Model, Network layer) in the protocol suite and is the addressing scheme used to determine the destination of data or network address. Basically IP is the universal protocol that allows any computer to communicate at any time. Protocols without a network layer use only a name (MAC) to identify a computer on a network.

TCP (Layer 4) sends datagrams to the Network layer (IP) and tells IP the source and destination address of the computer at the other end. IP’s job is to forward the packet to the destination address based on best path.

For related information see also OSI Model, Introduction to Networking, and Subnetting.