Thoughts on the National Research and Education Network, Komputer, More Hacking

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Network Working Group V. CerfRequest for Comments: 1167 CNRIJuly 1990THOUGHTS ON THE NATIONAL RESEARCH AND EDUCATION NETWORKStatus of this MemoThe memo provides a brief outline of a National Research andEducation Network (NREN). This memo provides information for theInternet community. It does not specify any standard. It is not astatement of IAB policy or recommendations.Distribution of this memo is unlimited.ABSTRACTThis contribution seeks to outline and call attention to some of themajor factors which will influence the form and structure of aNational Research and Education Network (NREN). It is implicitlyassumed that the system will emerge from the existing Internet.ACKNOWLEDGEMENTSThe author gratefully acknowledges support from the National ScienceFoundation, The Defense Advanced Research Projects Agency, theDepartment of Energy and the National Aeronautics and SpaceAdministration through cooperative agreement NCR-8820945. The authoralso acknowledges helpful comments from colleagues Ira Richer, BarryLeiner, Hans-Werner Braun and Robert Kahn. The opinions expressed inthis paper are the personal opinions of the author and do notrepresent positions of the U.S. Government, the Corporation forNational Research Initiatives or of the Internet Activities Board.In fact, the author isn't sure he agrees with everything in thepaper, either!A WORD ON TERMINOLOGYThe expression "national research and education network" is taken tomean "the U.S. National Research and Education Network" in thematerial which follows. It is implicitly assumed that similarinitiatives may arise in other countries and that a kind of GlobalResearch and Education Network may arise out of the existinginternational Internet system. However, the primary focus of thispaper is on developments in the U.S.Cerf [Page 1]RFC 1167 NREN July 1990FUNDAMENTALS1. 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 internationalenvironment consisting of a good many networks sponsored or owned andoperated by non-U.S. organizations around the world.2. There will continue to be special-purpose and mission-orientednetworks sponsored by the U.S. Government which will need to linkwith, if not directly support, the NREN.3. The basic technical networking architecture of the system willinclude local area networks, metropolitan, regional and wide-areanetworks. Some nets will be organized to support transit traffic andothers will be strictly parasitic.4. Looking towards the end of the decade, some of the networks may bemobile (digital, cellular). A variety of technologies may be used,including, but not limited to, high speed Fiber Data DistributionInterface (FDDI) nets, Distributed-Queue Dual Bus (DQDB) nets,Broadband Integrated Services Digital Networks (B-ISDN) utilizingAsynchronous Transfer Mode (ATM) switching fabrics as well asconventional Token Ring, Ethernet and other IEEE 802.X technology.Narrowband ISDN and X.25 packet switching technology network servicesare also likely play a role along with Switched Multi-megabit DataService (SMDS) provided by telecommunications carriers. It alsowould be fair to ask what role FTS-2000 might play in the system, atleast in support of government access to the NREN, and possibly insupport of national agency network facilities.5. The protocol architecture of the system will continue to exhibit alayered structure although the layering may vary from the present-dayInternet and planned Open Systems Interconnection structures in somerespects.6. The system will include servers of varying kinds required tosupport the general operation of the system (for example, networkmanagement facilities, name servers of various types, email, databaseand other kinds of information servers, multicast routers,cryptographic certificate servers) and collaboration support toolsincluding video/teleconferencing systems and other "groupware"facilities. Accounting and access control mechanisms will berequired.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 Servicesin the OSI area is an open issue (transport service bridges andCerf [Page 2]RFC 1167 NREN July 1990application level gateways are two possibilities).8. Provision must be made for experimental research in networking tosupport the continued technical evolution of the system. The NRENcan no more be a static, rigid system than the Internet has beensince its inception. Interconnection of experimental facilities withthe 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 toconsider the constituencies and stakeholders who have a role to playin the use of, provision of and evolution of NREN services. Theirinterests will affect the architecture of the NREN and the course ofits creation and evolution.NREN CONSTITUENTSThe UsersExtrapolating from the present Internet, the users of the systemwill be diverse. By legislative intent, it will include collegesand universities, government research organizations (e.g.,research laboratories of the Departments of Defense, Energy,Health and Human Services, National Aeronautics and SpaceAdministration), non-profit and for-profit research anddevelopment organizations, federally funded research anddevelopment centers (FFRDCs), R&D activities of privateenterprise, library facilities of all kinds, and primary andsecondary schools. The system is not intended to be discipline-specific.It is critical to recognize that even in the present Internet, ithas been possible to accommodate a remarkable amalgam of privateenterprise, academic institutions, government and militaryfacilities. Indeed, the very ability to accept such a diverseconstituency turns on the increasing freedom of the so-calledintermediate-level networks to accept an unrestricted set ofusers. The growth in the size and diversity of Internet users, ifit can be said to have been constrained at all, has been limitedin part by usage constraints placed on the federally-sponsorednational agency networks (e.g., NSFNET, NASA Science Internet,Energy Sciences Net, High Energy Physics Net, the recentlydeceased ARPANET, Defense Research Internet, etc.). Given thepurposes of these networks and the fiduciary responsibilities ofthe agencies that have created them, such usage constraints seemhighly appropriate. It may be beneficial to search for lessCerf [Page 3]RFC 1167 NREN July 1990constraining architectural paradigms, perhaps through the use ofbackbone facilities which are not federally-sponsored.The Internet does not quite serve the public in the same sensethat the telephone network(s) do (i.e., the Internet is not acommon carrier), although the linkages between the Internet andpublic electronic mail systems, private bulletin board systemssuch as FIDONET and commercial network services such as UUNET,ALTERNET and PSI, for example, make the system extremelyaccessible to a very wide variety of users.It will be important to keep in mind that, over time, anincreasing number of institutional users will support local areanetworks and will want to gain access to NREN by that means.Individual use will continue to rely on dial-up access and, as itis deployed, narrow-band ISDN. Eventually, metropolitan areanetworks and broadband ISDN facilities may be used to supportaccess to NREN. Cellular radio or other mobile communicationtechnologies may also become increasingly popular as access tools.The Service ProvidersIn its earliest stages, the Internet consisted solely ofgovernment-sponsored networks such as the Defense Department'sARPANET, Packet Radio Networks and Packet Satellite Networks.With the introduction of Xerox PARC's Ethernet, however, thingsbegan to change and privately owned and operated networks becamean integral part of the Internet architecture.For a time, there was a mixture of government-sponsored backbonefacilities and private local area networks. With the introductionof the National Science Foundation NSFNET, however, thearchitecture changed again to include intermediate-level networksconsisting of collections of commercially-produced routers andtrunk or access lines which connected local area networkfacilities to the government-sponsored backbones. Thegovernment-sponsored supercomputer centers (such as the NationalAerospace Simulator at NASA/AMES, the Magnetic Fusion EnergyComputing Center at Lawrence Livermore Laboratory and the half-... [ Pobierz całość w formacie PDF ]

Thoughts on the National Research and Education Network, Komputer, More Hacking

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