The first-ever computer-to-computer link was established on ARPANET (Advanced Research Projects Agency Network), the precursor to the Internet, on October 29, 1969.
Originally funded by ARPA (Advanced Research Projects Agency), now DARPA, within the United States Department of Defense, ARPANET was to be used for projects at universities and research laboratories in the US. The packet switching of the ARPANET was based on designs by British scientist Donald Davies and Lawrence Roberts of the Lincoln Laboratory.
Initially, ARPANET consisted of four IMPs at:
- the University of California, Los Angeles, which had an SDS Sigma 7 as the first computer attached to it;
- the Stanford Research Institute’s Augmentation Research Center, where Douglas Engelbart is credited with creating the NLS (oN-Line System) hypertext system, with an SDS 940 that ran NLS being the first host attached;
- the University of California, Santa Barbara with the Culler-Fried Interactive Mathematics Center’s IBM 360/75 running OS/MVT being the machine attached;
- And at the University of Utah’s Computer Science Department, running a DEC PDP-10 running TENEX.
The first message on the ARPANET was sent by UCLA student programmer Charles S Kline at 10:30 pm on October 29, from the campus’ Boelter Hall to the Stanford Research Institute’s SDS 940 host computer.
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