rfc1167.txt

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Network Working Group                                            V. Cerf
Request for Comments: 1167                                          CNRI
                                                               July 1990


        THOUGHTS ON THE NATIONAL RESEARCH AND EDUCATION NETWORK

Status of this Memo

   The memo provides a brief outline of a National Research and
   Education Network (NREN).  This memo provides information for the
   Internet community.  It does not specify any standard.  It is not a
   statement of IAB policy or recommendations.

   Distribution of this memo is unlimited.

ABSTRACT

   This contribution seeks to outline and call attention to some of the
   major factors which will influence the form and structure of a
   National Research and Education Network (NREN).  It is implicitly
   assumed that the system will emerge from the existing Internet.

ACKNOWLEDGEMENTS

   The author gratefully acknowledges support from the National Science
   Foundation, The Defense Advanced Research Projects Agency, the
   Department of Energy and the National Aeronautics and Space
   Administration through cooperative agreement NCR-8820945.  The author
   also acknowledges helpful comments from colleagues Ira Richer, Barry
   Leiner, Hans-Werner Braun and Robert Kahn.  The opinions expressed in
   this paper are the personal opinions of the author and do not
   represent positions of the U.S. Government, the Corporation for
   National Research Initiatives or of the Internet Activities Board.
   In fact, the author isn't sure he agrees with everything in the
   paper, either!

A WORD ON TERMINOLOGY

   The expression "national research and education network" is taken to
   mean "the U.S. National Research and Education Network" in the
   material which follows.  It is implicitly assumed that similar
   initiatives may arise in other countries and that a kind of Global
   Research and Education Network may arise out of the existing
   international Internet system.  However, the primary focus of this
   paper is on developments in the U.S.





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RFC 1167                          NREN                         July 1990


FUNDAMENTALS

   1. The NREN in the U.S. will evolve from the existing Internet base.
   By implication, the U.S. NREN will have to fit into an international
   environment consisting of a good many networks sponsored or owned and
   operated by non-U.S. organizations around the world.

   2. There will continue to be special-purpose and mission-oriented
   networks sponsored by the U.S. Government which will need to link
   with, if not directly support, the NREN.

   3. The basic technical networking architecture of the system will
   include local area networks, metropolitan, regional and wide-area
   networks.  Some nets will be organized to support transit traffic and
   others will be strictly parasitic.

   4. Looking towards the end of the decade, some of the networks may be
   mobile (digital, cellular).  A variety of technologies may be used,
   including, but not limited to, high speed Fiber Data Distribution
   Interface (FDDI) nets, Distributed-Queue Dual Bus (DQDB) nets,
   Broadband Integrated Services Digital Networks (B-ISDN) utilizing
   Asynchronous Transfer Mode (ATM) switching fabrics as well as
   conventional Token Ring, Ethernet and other IEEE 802.X technology.
   Narrowband ISDN and X.25 packet switching technology network services
   are also likely play a role along with Switched Multi-megabit Data
   Service (SMDS) provided by telecommunications carriers.  It also
   would be fair to ask what role FTS-2000 might play in the system, at
   least in support of government access to the NREN, and possibly in
   support of national agency network facilities.

   5. The protocol architecture of the system will continue to exhibit a
   layered structure although the layering may vary from the present-day
   Internet and planned Open Systems Interconnection structures in some
   respects.

   6. The system will include servers of varying kinds required to
   support the general operation of the system (for example, network
   management facilities, name servers of various types, email, database
   and other kinds of information servers, multicast routers,
   cryptographic certificate servers) and collaboration support tools
   including video/teleconferencing systems and other "groupware"
   facilities.  Accounting and access control mechanisms will be
   required.

   7. The system will support multiple protocols on an end to end basis.
   At the least, full TCP/IP and OSI protocol stacks will be supported.
   Dealing with Connectionless and Connection-Oriented Network Services
   in the OSI area is an open issue (transport service bridges and



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RFC 1167                          NREN                         July 1990


   application level gateways are two possibilities).

   8. Provision must be made for experimental research in networking to
   support the continued technical evolution of the system.  The NREN
   can no more be a static, rigid system than the Internet has been
   since its inception.  Interconnection of experimental facilities with
   the operational NREN must be supported.

   9. The architecture must accommodate the use of commercial services,
   private and Government-sponsored networks in the NREN system.

   Apart from the considerations listed above, it is also helpful to
   consider the constituencies and stakeholders who have a role to play
   in the use of, provision of and evolution of NREN services.  Their
   interests will affect the architecture of the NREN and the course of
   its creation and evolution.

NREN CONSTITUENTS

   The Users

      Extrapolating from the present Internet, the users of the system
      will be diverse.  By legislative intent, it will include colleges
      and universities, government research organizations (e.g.,
      research laboratories of the Departments of Defense, Energy,
      Health and Human Services, National Aeronautics and Space
      Administration), non-profit and for-profit research and
      development organizations, federally funded research and
      development centers (FFRDCs), R&D activities of private
      enterprise, library facilities of all kinds, and primary and
      secondary schools.  The system is not intended to be discipline-
      specific.

      It is critical to recognize that even in the present Internet, it
      has been possible to accommodate a remarkable amalgam of private
      enterprise, academic institutions, government and military
      facilities.  Indeed, the very ability to accept such a diverse
      constituency turns on the increasing freedom of the so-called
      intermediate-level networks to accept an unrestricted set of
      users.  The growth in the size and diversity of Internet users, if
      it can be said to have been constrained at all, has been limited
      in part by usage constraints placed on the federally-sponsored
      national agency networks (e.g., NSFNET, NASA Science Internet,
      Energy Sciences Net, High Energy Physics Net, the recently
      deceased ARPANET, Defense Research Internet, etc.).  Given the
      purposes of these networks and the fiduciary responsibilities of
      the agencies that have created them, such usage constraints seem
      highly appropriate.  It may be beneficial to search for less



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RFC 1167                          NREN                         July 1990


      constraining architectural paradigms, perhaps through the use of
      backbone facilities which are not federally-sponsored.

      The Internet does not quite serve the public in the same sense
      that the telephone network(s) do (i.e., the Internet is not a
      common carrier), although the linkages between the Internet and
      public electronic mail systems, private bulletin board systems
      such as FIDONET and commercial network services such as UUNET,
      ALTERNET and PSI, for example, make the system extremely
      accessible to a very wide variety of users.

      It will be important to keep in mind that, over time, an
      increasing number of institutional users will support local area
      networks and will want to gain access to NREN by that means.
      Individual use will continue to rely on dial-up access and, as it
      is deployed, narrow-band ISDN.  Eventually, metropolitan area
      networks and broadband ISDN facilities may be used to support
      access to NREN.  Cellular radio or other mobile communication
      technologies may also become increasingly popular as access tools.

   The Service Providers

      In its earliest stages, the Internet consisted solely of
      government-sponsored networks such as the Defense Department's
      ARPANET, Packet Radio Networks and Packet Satellite Networks.
      With the introduction of Xerox PARC's Ethernet, however, things
      began to change and privately owned and operated networks became
      an integral part of the Internet architecture.

      For a time, there was a mixture of government-sponsored backbone
      facilities and private local area networks.  With the introduction
      of the National Science Foundation NSFNET, however, the
      architecture changed again to include intermediate-level networks
      consisting of collections of commercially-produced routers and
      trunk or access lines which connected local area network
      facilities to the government-sponsored backbones.  The
      government-sponsored supercomputer centers (such as the National
      Aerospace Simulator at NASA/AMES, the Magnetic Fusion Energy
      Computing Center at Lawrence Livermore Laboratory and the half-
      dozen or so NSF-sponsored supercomputer centers) fostered the
      growth of communications networks specifically to support
      supercomputer access although, over time, these have tended to
      look more and more like general-purpose intermediate-level
      networks.

      Many, but not all, of the intermediate-level networks applied for
      and received seed funding from the National Science Foundation.
      It was and continues to be NSF's position, however, that such



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