Computer World. Матросова Т.А. - 91 стр.

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technology within the scientific community. Also during this period, other federal
agencies with computer-oriented research programs, notably the Department of
Energy (DOE) and the National Aeronautics and Space Administration (NASA),
created their own «community networks.»
The TCP/IP protocol adopted by DOD a few years earlier was only one of many
such standards. Although it was the only one that dealt explicitly with
internetworking of packet networks, its use was not yet mandated on the ARPANET.
However, on January 1, 1983, TCP/IP became the standard for the ARPANET,
replacing the older host protocol known as NCP. This step was in preparation for the
ARPANET-MILNET split, which was to occur about a year later. Mandating the use
of TCP/IP on the ARPANET encouraged the addition of local area networks and also
accelerated the growth in numbers of users and networks. At the same time, it led to a
rethinking of the process that ARPA was using to manage the evolution of the
network.
In 1983, ARPA replaced the ICCB with the Internet Activities Board (IAB). The
IAB was constituted similarly to the old ICCB, but the many issues of network
evolution were delegated to 10 task forces chartered by and reporting to the IAB. The
IAB was charged with assisting ARPA to meet its Internet-related R&D objectives;
the chair of the IAB was selected from the research community supported by ARPA.
ARPA also began to delegate to the IAB the responsibility for conducting the
standards-setting process.
Following the CSNET effort, NSF and ARPA worked together to expand the
number of users on the ARPANET, but they were constrained by the limitations that
DOD placed on the use of the network. By the mid-1980s, however, network
connectivity had become sufficiently central to the workings of the computer science
community that NSF became interested in broadening the use of networking to other
scientific disciplines. The NSF supercomputer centers program represented a major
stimulus to broader use of networks by providing limited access to the centers via the
ARPANET. At about the same time, ARPA decided to phase out its network research
program, only to reconsider this decision about a year later when the seeds for the
subsequent high-performance computer initiative were planted by the Reagan
administration and then-Sen. Albert Gore (D-Tenn.). In this period, NSF formulated a
strategy to assume responsibility for the areas of leadership that ARPA had formerly
held and planned to field an advanced network called NSFNET. NSFNET was to join
the NSF supercomputer centers with very high speed links, then 1.5 megabits per
second (mbps), and to provide members of the U.S. academic community access to
the NSF supercomputer centers and to one another.
Under a cooperative agreement between NSF and Merit, Inc., the NSFNET
backbone was put into operation in 1988 and, because of its higher speed, soon
replaced the ARPANET as the backbone of choice. In 1990, ARPA decommissioned
the last node of the ARPANET. It was replaced by the NSFNET backbone and a
series of regional networks most of which were funded by or at least started with
funds from the U.S. government and were expected to become self-supporting soon
thereafter. The NSF effort greatly expanded the involvement of many other groups in

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