The
Internet Protocol Suite (commonly known as
TCP/IP) is the set of
communications protocols used for the
Internet and other similar networks. It is named from two of the most important protocols in it the
Transmission Control Protocol (TCP) and the
Internet Protocol (IP), which were the first two networking protocols defined in this standard. Today's IP networking represents a synthesis of several developments that began to evolve in the 1960s and 1970s, namely the
Internet and LANs (
Local Area Networks), which emerged in the mid- to late-1980s, together with the advent of the
World Wide Web in the early 1990s.
The Internet Protocol Suite, like many protocol suites, may be viewed as a set of layers. Each layer solves a set of problems involving the transmission of data, and provides a well-defined service to the upper layer protocols based on using services from some lower layers. Upper layers are logically closer to the user and deal with more abstract data, relying on lower layer protocols to translate data into forms that can eventually be physically transmitted.
The TCP/IP model consists of four layers (RFC 1122).[1][2] From lowest to highest, these are the Link Layer, the Internet Layer, the Transport Layer, and the Application Layer.
The Internet Protocol Suite resulted from work done by the Defense Advanced Research Projects Agency (DARPA) in the early 1970s. After building the pioneering ARPANET "Advanced Research Projects Agency" in 1969, DARPA started work on a number of other data transmission technologies. In 1972, Robert E. Kahn was hired at the DARPA Information Processing Technology Office, where he worked on both satellite packet networks and ground-based radio packet networks, and recognized the value of being able to communicate across them. In the spring of 1973, Vinton Cerf, the developer of the existing ARPANET Network Control Program (NCP) protocol, joined Kahn to work on open-architecture interconnection models with the goal of designing the next protocol generation for the ARPANET.This is also known as DOD department of defense model.
