Computer World. Матросова Т.А. - 89 стр.

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88
Origins of the Internet
The Internet originated in the early 1970s as part of an Advanced Research
Projects Agency (ARPA) research project on «internetworking.» At that time, ARPA
demonstrated the viability of packet switching for computer-to-computer
communication in its flagship network, the ARPANET, which linked several dozen
sites and perhaps twice that number of computers into a national network for
computer science research. Extensions of the packet-switching concept to satellite
networks and to ground-based mobile radio networks were also under development
by ARPA, and segments of industry (notably not the traditional telecommunications
sector) were showing great interest in providing commercial packet network services.
It seemed likely that at least three or four distinct computer networks would exist by
the mid-1970s and that the ability to communicate among these networks would be
highly desirable if not essential.
In a well-known joint effort that took place around 1973, Robert Kahn, then at
ARPA, and Vinton Cerf, then at Stanford, collaborated on the design of an
internetwork architecture that would allow packet networks of different kinds to
interconnect and machines to communicate across the set of interconnected networks.
The internetwork architecture was based on a protocol that came to be known as
TCP/IP. The period from 1974 to 1978 saw four successively refined versions of the
protocol implemented and tested by ARPA research contractors in academia and
industry, with version number four eventually becoming standardized. The TCP/IP
protocol was used initially to connect the ARPANET, based on 50 kilobits per second
(kbps) terrestrial lines; the Packet Radio Net (PRNET), based on dual rate 400/100
kbps spread spectrum radios; and the Packet Satellite Net (SATNET), based on a 64
kbps shared channel on Intelsat IV. The initial satellite Earth stations were in the
United States and the United Kingdom, but subsequently additional Earth stations
were activated in Norway, Germany, and Italy. Several experimental PRNETs were
connected, including one in the San Francisco Bay area. At the time, no personal
computers, workstations, or local area networks were available commercially, and the
mac hines invo lved w ere main ly large-sc ale sc ientif ic time-sharing sys tems. Remote
access to time-sharing systems was made available by terminal access servers.
The technical tasks involved in constructing this initial ARPA Internet revolved
mainly around the configuration of «gateways,» now known as routers, to connect
different networks, as well as the development of TCP/IP software in the computers.
These were both engineering-intensive tasks that took considerable expertise to
accomplish. By the mid-1980s, industry began offering commercial gateways and
routers and started to make available TCP/IP software for some workstations,
minicomputers, and mainframes. Before this, these capabilities were unavailable;
they had to be handcrafted by the engineers at each site.
In 1979, ARPA established a small Internet Configuration Control Board
(ICCB), most of whose members belonged to the research community, to help with
this process and to work with ARPA in evolving the Internet design. The
establishment of the ICCB was important because it brought a wider segment of the
research community into the Internet decision-making process, which until then had

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