Editing ARPANET (section)

== Inspiration ==

Historically, voice and [[data communication]]s were based on methods of [[circuit switching]], as exemplified in the traditional telephone network, wherein each telephone call is allocated a dedicated end-to-end electronic connection between the two communicating stations. The connection is established by switching systems that connected multiple intermediate call legs between these systems for the duration of the call.

The traditional model of the circuit-switched telecommunication network was challenged in the early 1960s by [[Paul Baran]] at the [[RAND Corporation]], who had been researching systems that could sustain operation during partial destruction, such as by nuclear war. He developed the theoretical model of ''distributed adaptive message block switching''.<ref name="RAND corporation">{{cite web|url=https://www.rand.org/about/history/baran.list.html |title=Paul Baran and the Origins of the Internet |publisher=RAND corporation |access-date=29 March 2011}}</ref> However, the telecommunication establishment rejected the development in favor of existing models. [[Donald Davies]] at the United Kingdom's [[National Physical Laboratory (United Kingdom)|National Physical Laboratory]] (NPL) independently arrived at a similar concept in 1965.<ref>{{cite web|last=Scantlebury|first=Roger|title=''Internet pioneers airbrushed from history''|url=https://www.theguardian.com/technology/2013/jun/25/internet-pioneers-airbrushed-from-history|date=25 June 2013|work=The Guardian|access-date=1 August 2015}}</ref><ref>{{cite web|title=''Packets of data were the key...''|url=http://www.npl.co.uk/news/packets-of-data|publisher=NPL|access-date=1 August 2015}}</ref>

The earliest ideas for a [[computer network]] intended to allow general communications among computer users were formulated by [[computer scientist]] [[J. C. R. Licklider]] of [[Bolt Beranek and Newman]] (BBN), in April 1963, in memoranda discussing the concept of the "[[Intergalactic Computer Network]]". Those ideas encompassed many of the features of the contemporary Internet. In October 1963, Licklider was appointed head of the Behavioral Sciences and Command and Control programs at the Defense Department's [[Advanced Research Projects Agency]] (ARPA). He convinced [[Ivan Sutherland]] and [[Robert Taylor (computer scientist)|Bob Taylor]] that this network concept was very important and merited development, although Licklider left ARPA before any contracts were assigned for development.<ref>{{cite web|url=http://www.livinginternet.com/internet/i/ii_licklider.htm|title=J.C.R. Licklider And The Universal Network|website=Living Internet|access-date=2021-03-19}}</ref>

Sutherland and Taylor continued their interest in creating the network, in part, to allow ARPA-sponsored researchers at various corporate and academic locales to utilize computers provided by ARPA, and, in part, to quickly distribute new software and other [[computer science]] results.<ref>{{cite web|url=http://www.livinginternet.com/internet/i/ii_ipto.htm|title=IPTO – Information Processing Techniques Office|website=Living Internet|access-date=2021-03-19}}</ref> Taylor had three computer terminals in his office, each connected to separate computers, which ARPA was funding: one for the [[System Development Corporation]] (SDC) [[AN/FSQ-32|Q-32]] in [[Santa Monica]], one for [[Project Genie]] at the [[University of California, Berkeley]], and another for [[Multics]] at the [[Massachusetts Institute of Technology]]. Taylor recalls the circumstance: "For each of these three terminals, I had three different sets of user commands. So, if I was talking online with someone at S.D.C., and I wanted to talk to someone I knew at Berkeley, or M.I.T., about this, I had to get up from the S.D.C. terminal, go over and log into the other terminal and get in touch with them. I said, 'Oh Man!', it's obvious what to do: If you have these three terminals, there ought to be one terminal that goes anywhere you want to go. That idea is the ARPANET".<ref>{{cite news |title=An Internet Pioneer Ponders the Next Revolution |first=John |last=Markoff |url=http://partners.nytimes.com/library/tech/99/12/biztech/articles/122099outlook-bobb.html |work=The New York Times |access-date=20 September 2008 | date=20 December 1999| archive-url= https://web.archive.org/web/20080922095019/http://partners.nytimes.com/library/tech/99/12/biztech/articles/122099outlook-bobb.html| archive-date= 22 September 2008 | url-status= live}}</ref>

Donald Davies' work caught the attention of ARPANET developers at [[Symposium on Operating Systems Principles]] in October 1967.<ref name="Isaacson2014"/> He gave the first public presentation, having coined the term ''[[packet switching]]'', in August 1968 and incorporated it into the [[NPL network]] in England.<ref>{{Cite web|last1=Smith|first1=Ed|last2=Miller|first2=Chris|last3=Norton|first3=Jim |title=Packet Switching: The first steps on the road to the information society |url=https://www.npl.co.uk/getattachment/about-us/History/Famous-faces/Donald-Davies/UK-role-in-Packet-Switching-(1).pdf.aspx}}</ref><ref>{{cite news|title=The accelerator of the modern age |date=5 August 2008 |url=http://news.bbc.co.uk/1/hi/technology/7541123.stm|work=BBC News|access-date=19 May 2009}}</ref> The NPL network and ARPANET were the first two networks in the world to implement packet switching.<ref name="Roberts1978">{{cite web|last1=Roberts|first1=Lawrence G.|date=November 1978|title=The Evolution of Packet Switching |url=http://www.packet.cc/files/ev-packet-sw.html|access-date=9 April 2016|archive-date=24 March 2016 |archive-url=https://web.archive.org/web/20160324033133/http://www.packet.cc/files/ev-packet-sw.html|url-status=dead}}</ref><ref name="C. Hempstead, W. Worthington">{{cite book |author1=C. Hempstead |url=https://books.google.com/books?id=2ZCNAgAAQBAJ&q=NPL%20Network&pg=PA574 |title=Encyclopedia of 20th-Century Technology |author2=W. Worthington |date=8 August 2005 |publisher=[[Routledge]] 8 August 2005, 992 pages, (edited by C. Hempstead, W. Worthington) |isbn=978-1-135-45551-4 |access-date=15 August 2015}}</ref><ref name="Davies">{{cite web |title=Donald Davies |url=http://www.internethalloffame.org/inductees/donald-davies |website=internethalloffame.org}}</ref> Roberts said the computer networks built in the 1970s were similar "in nearly all respects" to Davies' original 1965 design.<ref name=":2">{{cite journal |last1=Roberts |first1=Lawrence G.|date=November 1978|title=The Evolution of Packet Switching |url=http://www.ismlab.usf.edu/dcom/Ch10_Roberts_EvolutionPacketSwitching_IEEE_1978.pdf|journal=IEEE Invited Paper|access-date=September 10, 2017 |quote=In nearly all respects, Davies' original proposal, developed in late 1965, was similar to the actual networks being built today.|archive-url=https://web.archive.org/web/20181231092936/http://www.ismlab.usf.edu/dcom/Ch10_Roberts_EvolutionPacketSwitching_IEEE_1978.pdf|archive-date=31 December 2018|url-status=dead}}</ref>