diff options
Diffstat (limited to 'doc/rfc/rfc1167.txt')
| -rw-r--r-- | doc/rfc/rfc1167.txt | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/doc/rfc/rfc1167.txt b/doc/rfc/rfc1167.txt new file mode 100644 index 0000000..7bebde4 --- /dev/null +++ b/doc/rfc/rfc1167.txt @@ -0,0 +1,451 @@ + + + + + + +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] +
\ No newline at end of file |