Editing Packet switching (section)

{{short description|Method for transmitting data over a computer network}}
{{Use American English|date=November 2022}}

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| link1             = Paul Baran
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| footer            = [[Paul Baran]] and [[Donald Davies]] independently invented the concept of digital packet switching used in modern computer networking including the Internet.<ref name=":16"/><ref name="Pelkeyp42" /><ref name="NIHF2007"/>
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In [[telecommunications]], '''packet switching''' is a method of grouping [[Data (computing)|data]] into short messages in fixed format, i.e. ''[[network packet|packets]],'' that are transmitted over a digital [[Telecommunications network|network]]. Packets consist of a [[header (computing)|header]] and a [[payload (computing)|payload]]. Data in the header is used by networking hardware to direct the packet to its destination, where the payload is extracted and used by an [[operating system]], [[application software]], or [[Protocol stack|higher layer protocols]]. Packet switching is the primary basis for data communications in [[computer networks]] worldwide.

During the early 1960s, American engineer [[Paul Baran]] developed a concept he called ''distributed adaptive message block switching'', with the goal of providing a [[fault-tolerant]], efficient routing method for telecommunication messages as part of a research program at the [[RAND Corporation]], funded by the [[United States Department of Defense]]. His ideas contradicted then-established principles of [[Bandwidth allocation|pre-allocation of network bandwidth]], exemplified by the development of telecommunications in the [[Bell System]]. The new concept found little resonance among network implementers until the independent work of Welsh computer scientist [[Donald Davies]] at the [[National Physical Laboratory (United Kingdom)|National Physical Laboratory]] in 1965. Davies coined the term ''packet switching'' and inspired numerous packet switching networks in the decade following, including the incorporation of the concept into the design of the [[ARPANET]] in the United States and the [[CYCLADES]] network in France. The ARPANET and CYCLADES were the primary precursor networks of the modern [[Internet]].