Network Working Group                                            V. CerfRequest for Comments: 1167                                          CNRI                                                               July 1990        THOUGHTS ON THE NATIONAL RESEARCH AND EDUCATION NETWORKStatus 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.Cerf                                                            [Page 1]RFC 1167                          NREN                         July 1990FUNDAMENTALS   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 andCerf                                                            [Page 2]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 lessCerf                                                            [Page 3]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