RFC 1462 (rfc1462) - Page 3 of 11


FYI on "What is the Internet?"



Alternative Format: Original Text Document



RFC 1462                 What is the Internet?                  May 1993


   than connecting to a single large timesharing computer per site,
   organizations wanted to connect the ARPAnet to their entire local
   network. This would allow all the computers on that LAN to access
   ARPAnet facilities. About the same time, other organizations started
   building their own networks using the same communications protocols
   as the ARPAnet: namely, IP and its relatives. It became obvious that
   if these networks could talk together, users on one network could
   communicate with those on another; everyone would benefit.

   One of the most important of these newer networks was the NSFNET,
   commissioned by the National Science Foundation (NSF), an agency of
   the U.S. government. In the late 80's the NSF created five
   supercomputer centers. Up to this point, the world's fastest
   computers had only been available to weapons developers and a few
   researchers from very large corporations. By creating supercomputer
   centers, the NSF was making these resources available for any
   scholarly research. Only five centers were created because they were
   so expensive--so they had to be shared. This created a communications
   problem: they needed a way to connect their centers together and to
   allow the clients of these centers to access them.  At first, the NSF
   tried to use the ARPAnet for communications, but this strategy failed
   because of bureaucracy and staffing problems.

   In response, NSF decided to build its own network, based on the
   ARPAnet's IP technology. It connected the centers with 56,000 bit per
   second (56k bps) telephone lines.  (This is roughly the ability to
   transfer two full typewritten pages per second.  That's slow by
   modern standards, but was reasonably fast in the mid 80's.)  It was
   obvious, however, that if they tried to connect every university
   directly to a supercomputing center, they would go broke. You pay for
   these telephone lines by the mile. One line per campus with a
   supercomputing center at the hub, like spokes on a bike wheel, adds
   up to lots of miles of phone lines. Therefore, they decided to create
   regional networks. In each area of the country, schools would be
   connected to their nearest neighbor. Each chain was connected to a
   supercomputer center at one point and the centers were connected
   together. With this configuration, any computer could eventually
   communicate with any other by forwarding the conversation through its
   neighbors.

   This solution was successful--and, like any successful solution, a
   time came when it no longer worked. Sharing supercomputers also
   allowed the connected sites to share a lot of other things not
   related to the centers. Suddenly these schools had a world of data
   and collaborators at their fingertips. The network's traffic
   increased until, eventually, the computers controlling the network
   and the telephone lines connecting them were overloaded. In 1987, a
   contract to manage and upgrade the network was awarded to Merit



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