USSR's launch of Sputnik spurred the United States to create the
Advanced Research Projects Agency (ARPA, later known as the Defense
Advanced Research Projects Agency) in February 1958 to regain
a technological lead. ARPA created the Information Processing
Technology Office (IPTO) to further the research of the Semi Automatic
Ground Environment program, which had networked country-wide radar
systems together for the first time. J. C. R. Licklider was selected
to head the IPTO, and saw universal networking as a potential
unifying human revolution. Licklider recruited Lawrence Roberts
to head a project to implement a network, and Roberts based the
technology on the work of Paul Baran who had written an exhaustive
study for the U.S. Air Force that recommended packet switching
(as opposed to Circuit switching) to make a network highly robust
and survivable. After much work, the first node went live at UCLA
on October 29, 1969 on what would be called the ARPANET, the "eve"
network of today's Internet.
first TCP/IP wide area network was operational by 1 January 1983
, when the United States' National Science Foundation (NSF) constructed
a university network backbone that would later become the NSFNet.
(This date is held by some to be technically that of the birth
of the Internet.) It was then followed by the opening of the network
to commercial interests in 1985. Important separate networks that
offered gateways into, then later merged into the NSFNet include
Usenet, Bitnet and the various commercial and educational X.25
Compuserve and JANET. Telenet (later called Sprintnet), was a
large privately-funded national computer network with free dialup
access in cities throughout the U.S. that had been in operation
since the 1970s. This network eventually merged with the others
in the 1990s as the TCP/IP protocol became increasingly popular.
The ability of TCP/IP to work over these pre-existing communication
networks allowed for a great ease of growth. Use of Internet as
a phrase to describe a single global TCP/IP network originated
around this time.