The Network Control Protocol (NCP) for the ARPANET was first implemented in 1970. On the ARPANET, the starting point for host-to-host communication in 1969 was the 1822 protocol, which defined the transmission of messages to an IMP. One of the first uses of the term protocol in a data-commutation context occurs in a memorandum entitled A Protocol for Use in the NPL Data Communications Network written by Roger Scantlebury and Keith Bartlett in April 1967. As the PSTN and Internet converge, the standards are also being driven towards convergence.Ĭommunicating systems History The ITU-T handles telecommunications protocols and formats for the public switched telephone network (PSTN). The IEEE (Institute of Electrical and Electronics Engineers) handles wired and wireless networking and the International Organization for Standardization (ISO) handles other types. Internet communication protocols are published by the Internet Engineering Task Force (IETF).
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A group of protocols designed to work together is known as a protocol suite when implemented in software they are a protocol stack. Multiple protocols often describe different aspects of a single communication. An alternate formulation states that protocols are to communication what algorithms are to computation. A programming language describes the same for computations, so there is a close analogy between protocols and programming languages: protocols are to communication what programming languages are to computations.
To reach an agreement, a protocol may be developed into a technical standard. Communication protocols have to be agreed upon by the parties involved.
The specified behavior is typically independent of how it is to be implemented.
Each message has an exact meaning intended to elicit a response from a range of possible responses pre-determined for that particular situation. Ĭommunicating systems use well-defined formats for exchanging various messages. Protocols may be implemented by hardware, software, or a combination of both. The protocol defines the rules, syntax, semantics and synchronization of communication and possible error recovery methods. System for exchanging messages between computing systemsĪ communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity.