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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.

Cerf [Page 1] 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

Cerf [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 less

Cerf [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
    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

Cerf [Page 4] RFC 1167 NREN July 1990

    direct subsidies should diminish over time and that the
    intermediate networks should become self-sustaining.  To
    accomplish this objective, the intermediate-level networks have
    been turning to an increasingly diverse user constituency (see
    section above).
    The basic model of government backbones, consortium intermediate
    level nets and private local area networks has served reasonably
    well during the 1980's but it would appear that newer
    telecommunications technologies may suggest another potential
    paradigm.  As the NSFNET moves towards higher speed backbone
    operation in the 45 Mb/s range, the importance of carrier
    participation in the enterprise has increased.  The provision of
    backbone capacity at attractive rates by the inter-exchange
    carrier (in this case, MCI Communications Corporation) has been
    crucial to the feasibility of deploying such a high speed system.
    As the third phase of the NREN effort gets underway, it is
    becoming increasingly apparent that the "federally-funded
    backbone" model may and perhaps even should or must give way to a
    vision of commercially operated, gigabit speed systems to which
    the users of the NREN have access.  If there is federal subsidy in
    the new paradigm, it might come through direct provision of
    support for networking at the level of individual research grant
    or possibly through a system of institutional vouchers permitting
    and perhaps even mandating institution-wide network planning and
    provision.  This differs from the present model in which the
    backbone networks are essentially federally owned and operated or
    enjoy significant, direct federal support to the provider of the
    service.
    The importance of such a shift in service provision philosophy
    cannot be over-emphasized.  In the long run, it eliminates
    unnecessary restrictions on the use and application of the
    backbone facilities, opening up possibilities for true ubiquity of
    access and use without the need for federal control, except to the
    extent that any such services are considered in need of
    regulation, perhaps.  The same arguments might be made for the
    intermediate level systems (metropolitan and regional area access
    networks).  This does NOT mean that private networks ranging from
    local consortia to inter-continental systems will be ruled out.
    The economics of private networking may still be favorable for
    sufficiently heavy usage.  It does suggest, however, that
    achieving scale and ubiquity may largely rely on publicly
    accessible facilities.

Cerf [Page 5] RFC 1167 NREN July 1990

 The Vendors
    Apart from service provision, the technology available to the
    users and the service providers will come largely from commercial
    sources.  A possible exception to this may be the switches used in
    the gigabit testbed effort, but ultimately, even this technology
    will have to be provided commercially if the system is to achieve
    the scale necessary to serve as the backbone of the NREN.
    An important consequence of this observation is that the NREN
    architecture should be fashioned in such a way that it can be
    constructed from technology compatible with carrier plans and
    available from commercial telecommunications equipment suppliers.
    Examples include the use of SONET (Synchronous Optical Network)
    optical transmission technology, Switched Multimegabit Data
    Services offerings (metropolitan area networks), Asynchronous
    Transmission Mode (ATM) switches, frame relays, high speed,
    multi-protocol routers, and so on.  It is somewhat unclear what
    role the public X.25 networks will play, especially where narrow
    and broadband ISDN services are available, but it is also not
    obvious that they ought to be written off at this point.  Where
    there is still research and development activity (such as in
    network management), the network R&D community can contribute
    through experimental efforts and through participation in
    standards-making activities (e.g., ANSI, NIST, IAB/IETF, Open
    NMF).

OPERATIONS

 It seems clear that the current Internet and the anticipated NREN
 will have to function in a highly distributed fashion.  Given the
 diversity of service providers and the richness of the constituent
 networks (as to technology and ownership), there will have to be a
 good deal of collaboration and cooperation to make the system work.
 One can see the necessity for this, based on the existing voice
 network in the U.S.  with its local and inter-exchange carrier (IEC)
 structure.  It should be noted that in the presence of the local and
 IEC structure, it has proven possible to support private and virtual
 private networking as well.  The same needs to be true of the NREN.
 A critical element of any commercial service is accounting and
 billing.  It must be possible to identify users (billable parties,
 anyway) and to compute usage charges.  This is not to say that the
 NREN component networks must necessarily bill on the basis of usage.
 It may prove preferable to have fixed access charges which might be
 modulated by access data rate, as some of the intermediate-level
 networks have found.  It would not be surprising to find a mixture of
 charging policies in which usage charges are preferable for small

Cerf [Page 6] RFC 1167 NREN July 1990

 amounts of use and flat rate charges are preferred for high volume
 use.
 It will be critical to establish a forum in which operational matters
 can be debated and methods established to allow cooperative operation
 of the entire system.  A number of possibilities present themselves:
 use of the Internet Engineering Task Force as a basis, use of
 existing telecommunication carrier organizations, or possibly a
 consortium of all service providers (and private network operators?).
 Even if such an activity is initiated through federal action, it may
 be helpful, in the long run, if it eventually embraces a much wider
 community.
 Agreements are needed on the technical foundations for network
 monitoring and management, for internetwork accounting and exchange
 payments, for problem identification, tracking, escalation and
 resolution.  A framework is needed for the support of users of the
 aggregate NREN.  This suggests cooperative agreements among network
 information centers, user service and support organizations to begin
 with.  Eventually, the cost of such operations will have to be
 incorporated into the general cost of service provision.  The federal
 role, even if it acts as catalyst in the initial stages, may
 ultimately focus on the direct support of the users of the system
 which it finds it appropriate to support and subsidize (e.g., the
 research and educational users of the NREN).
 A voucher system has been proposed, in the case of the NREN, which
 would permit users to choose which NREN service provider(s) to
 engage.  The vouchers might be redeemed by the service providers in
 the same sort of way that food stamps are redeemed by supermarkets.
 Over time, the cost of the vouchers could change so that an initial
 high subsidy from the federal government would diminish until the
 utility of the vouchers vanished and decisions would be made to
 purchase telecommunications services on a pure cost/benefit basis.

IMPORTANCE OF COMMERCIAL INTERESTS

 The initial technical architecture should incorporate commercial
 service provision where possible so as to avoid the creation of a
 system which is solely reliant on the federal government for its
 support and operation.  It is anticipated that a hybrid system will
 develop but, for example, it is possible that the gigabit backbone
 components of the system might be strictly commercial from the start,
 even if the lower speed components of the NREN vary from private, to
 public to federally subsidized or owned and operated.

Cerf [Page 7] RFC 1167 NREN July 1990

CONCLUSIONS

 The idea of creating a National Research and Education Network has
 captured the attention and enthusiasm of an extraordinarily broad
 collection of interested parties.  I believe this is in part a
 consequence of the remarkable range of new services and facilities
 which could be provided once the network infrastructure is in place.
 If the technology of the NREN is commercially viable, one can readily
 imagine that an economic engine of considerable proportions might
 result from the widespread accessibility of NREN-like facilities to
 business sector.

Security Considerations

 Security issues are not discussed in this memo.

Author's Address

 Vinton G. Cerf
 Corporation for National Research Initiatives
 1895 Preston White Drive, Suite 100
 Reston, VA 22091
 EMail: vcerf@NRI.Reston.VA.US
 Phone: (703) 620-8990

Cerf [Page 8]

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