NSFNET Backbone

The US National Science Foundation (NSF) became a major player in Internet operations and development in 1985. At this time, the NSF funded the development of five supercomputer centers. It decided to provide a high-speed network linking these supercomputer centers; it also desired to make these supercomputer resources available to the US academic and research community. This desire led, in 1985, to the NSF starting the NSF Network -- which, for nearly a decade, was to provide the primary Internet backbone connectivity within the United States.

The NSFNET originally consisted of 56-kbit data circuits[3] connecting its five supercomputer centers. However, NSF policy allowed nearly unrestricted academic access to their network for academic and research purposes. By this time, numerous regional academic networks existed; many connected to the existing NSFNET. As a result, the NSFNET quickly became a operational backbone for much traffic unrelated to supercomputing -- electronic mail, file transfer, and various other uses were common. NSF first upgraded their network to a thirteen-node T-1 network in July, 1988

Image obtained from www.boardwatch.com/isp/nsfnet.jpg

Due to rapidly increasing traffic, the NSFNET backbone was again upgraded, less than three and one-half years later, to a sixteen-node T3 network (November, 1991).

Image obtained from www.cise.nsf.gov/ncri/Oldnsfnetmap.gif

The original NSFNET charter excluded commercial uses. However, by the early 1990s a great deal of the traffic on NSFNET was commercial in nature. Many commercial networks obtained connections to the NSFNET; though a Commercial Internet Exchange existed, the bulk of Internet traffic traversed the NSFNET backbone. Additionally, the NSFNET was being operated by a largely commercial enterprise, Advanced Networks and Services (ANS), operating under contract to Merit Network, Incorporated. While both of these corporations were originally formed as nonprofit entities, by the early 1990s ANS had formed a for-profit subsidiary [4]and was in de facto competition with other national backbone providers for commercial Internet traffic.

In order to avoid competition with private industry, in May 1993 the NSF announced its intention to privatize Internet backbone operations and to return NSFNET to a research network. This was accomplished on April 30, 1995, when NSFNET terminated Internet backbone operations [5] in favor of a new, commercially operated Internet architecture.

Further information on Merit Network's involvement in NSFNET can be obtained here[6].

Further information on Advanced Networks and Services involvement in NSFNET can be obtained here[7].

Further information concerning current NSFNET operations can be obtained here[8].

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