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Network Working Group                                    Barry M. LeinerRequest for Comments: 1017                                         RIACS                                                             August 1987Network Requirements for Scientific Research              Internet Task Force on Scientific ComputingSTATUS OF THIS MEMO   This RFC identifies the requirements on communication networks for   supporting scientific research.  It proposes some specific areas for   near term work, as well as some long term goals.  This is an "idea"   paper and discussion is strongly encouraged.  Distribution of this   memo is unlimited.INTRODUCTION   Computer networks are critical to scientific research.  They are   currently being used by portions of the scientific community to   support access to remote resources (such as supercomputers and data   at collaborator's sites) and collaborative work through such   facilities as electronic mail and shared databases.  There is   considerable movement in the direction of providing these   capabilities to the broad scientific community in a unified manner,   as evidence by this workshop. In the future, these capabilities will   even be required in space, as the Space Station becomes a reality as   a scientific research resource.   The purpose of this paper is to identify the range of requirements   for networks that are to support scientific research.  These   requirements include the basic connectivity provided by the links and   switches of the network through the basic network functions to the   user services that need to be provided to allow effective use of the   interconnected network.  The paper has four sections.  The first   section discusses the functions a user requires of a network.  The   second section discusses the requirements for the underlying link and   node infrastructure while the third proposes a set of specifications   to achieve the functions on an end-to-end basis.  The fourth section   discusses a number of network-oriented user services that are needed   in addition to the network itself.  In each section, the discussion   is broken into two categories.  The first addresses near term   requirements: those capabilities and functions that are needed today   and for which technology is available to perform the function.  The   second category concerns long term goals: those capabilities for   which additional research is needed.   This RFC was produced by the IAB Task force a Scientific Computing,Leiner                                                          [Page 1]

RFC 1017          Requirements for Scientific Research       August 1987   which is chartered to investigate advanced networking requirements   that result from scientific applications.  Work reported herein was   supported in part by Cooperative Agreement NCC 2-387 from the   National Aeronautics and Space Administration (NASA) to the   Universities Space Research Association (USRA).1.  NETWORK FUNCTIONS   This section addresses the functions and capabilities that networks   and particularly internetworks should be expected to support in the   near term future.Near Term Requirements   There are many functions that are currently available to subsets of   the user community.  These functions should be made available to the   broad scientific community.User/Resource Connectivity   Undoubtedly the first order of business in networking is to provide   interconnectivity of users and the resources they need.  The goal in   the near term for internetworking should be to extend the   connectivity as widely as possible, i.e. to provide ubiquitous   connectivity among users and between users and resources.  Note that   the existence of a network path between sites does not necessarily   imply interoperability between communities and or resources using   non-compatible protocol suites.  However, a minimal set of functions   should be provided across the entire user community, independent of   the protocol suite being used.  These typically include electronic   mail at a minimum, file transfer and remote login capabilities must   also be provided.Home Usage   One condition that could enhance current scientific computing would   be to extend to the home the same level of network support that the   scientist has available in his office environment.  As network access   becomes increasingly widespread, the extension to the home will allow   the user to continue his computing at home without dramatic changes   in his work habits, based on limited access.Charging   The scientific user should not have to worry about the costs of data   communications any more than he worries about voice communications   (his office telephone), so that data communications becomes an   integral and low-cost part of our national infrastructure.  ThisLeiner                                                          [Page 2]

RFC 1017          Requirements for Scientific Research       August 1987   implies that charges for network services must NOT be volume   sensitive and must NOT be charged back to the individual.  Either of   these conditions forces the user to consider network resources as   scarce and therefore requiring his individual attention to conserve   them.  Such attention to extraneous details not only detracts from   the research, but fundamentally impacts the use and benefit that   networking is intended to supply.  This does not require that   networking usage is free.  It should be either be low enough cost   that the individual does not have to be accountable for "normal"   usage or managed in such a manner that the individual does not have   to be concerned with it on a daily basis.Applications   Most applications, in the near term, which must be supported in an   internetwork environment are essentially extensions of current ones.   Particularly:      Electronic Mail         Electronic mail will increase in value as the extended         interconnectivity provided by internetworking provides a much         greater reachability of users.      Multimedia Mail         An enhancement to text based mail which includes capabilities         such as figures, diagrams, graphs, and digitized voice.      Multimedia Conferencing         Network conferencing is communication among multiple people         simultaneously.  Conferencing may or may not be done in "real         time", that is all participants may not be required to be on-         line at the same time.  The multimedia supported may include         text, voice, video, graphics, and possibly other capabilities.      File Transfer         The ability to transfer data files.      Bulk Transfer         The ability to stream large quantities of data.      Interactive Remote Login         The ability to perform remote terminal connections to hosts.Leiner                                                          [Page 3]

RFC 1017          Requirements for Scientific Research       August 1987      Remote Job Entry         The ability to submit batch jobs for processing to remote hosts         and receive output.         Applications which need support in the near term but are NOT         extensions of currently supported applications include:      Remote Instrument Control         This normally presumes to have a human in the "control loop".         This condition relaxes the requirements on the (inter)network         somewhat as to response times and reliability.  Timing would be         presumed to be commensurate with human reactions and         reliability would not be as stringent as that required for         completely automatic control.      Remote Data Acquisition         This supports the collection of experimental data where the         experiment is remotely located from the collection center.         This requirement can only be satisfied when the bandwidth,         reliability, and predictability of network response are         sufficient.  This cannot be supported in the general sense         because of the enormous bandwidth, very high reliability,         and/or guaranteed short response time required for many         experiments.   These last two requirements are especially crucial when one considers   remote experimentation such as will be performed on the Space   Station.Capabilities   The above applications could be best supported on a network with   infinite bandwidth, zero delay, and perfect reliability.   Unfortunately, even currently feasible approximations to these levels   of capabilities can be very expensive. Therefore, it can be expected   that compromises will be made for each capability and between them,   with different balances struck between different networks.  Because   of this, the user must be given an opportunity to declare which   capability or capabilities is/are of most interest-most likely   through a "type-of-service" required declaration.  Some examples of   possible trade-offs: File Transport Normally requires high   reliability primarily and high bandwidth secondarily. Delay is not as   important.Leiner                                                          [Page 4]

RFC 1017          Requirements for Scientific Research       August 1987      Bulk Transport         Some applications such as digitized video might require high         bandwidth as the most important capability.  Depending on the         application, delay would be second, and reliability of lesser         importance.  Image transfers of scientific data sometimes will         invert the latter two requirements.      Interactive Traffic         This normally requires low delay as a primary consideration.         Reliability may be secondary depending on the application.         Bandwidth would usually be of least importance.Standards    The use of standards in networking is directed toward    interoperability and availability of commercial equipment.  However,    as stated earlier, full interoperability across the entire    scientific community is probably not a reasonable goal for    internetworking in the near term because of the protocol mix now    present.  That is not to say, though, that the use of standards    should not be pursued on the path to full user interoperability.    Standards, in the context of near term goal support, include:Media Exchange Standards   Would allow the interchange of equations, graphics, images, and data   bases as well as text.Commercially Available Standards   Plug compatible, commercially available standards will allow a degree   of interoperability prior to the widespread availability of the ISO   standard protocols.Long Term Goals   In the future, the internetwork should be transparent communications   between users and resources, and provide the additional network   services required to make use of that communications.  A user should   be able to access whatever resources are available just as if the   resource is in the office.  The same high level of service should   exist independent of which network one happens to be on.  In fact,   one should not even be able to tell that the network is there!   It is also important that people be able to work effectively while at   home or when traveling.  Wherever one may happen to be, it should beLeiner                                                          [Page 5]

RFC 1017          Requirements for Scientific Research       August 1987   possible to "plug into" the internetwork and read mail, access files,   control remote instruments, and have the same kind of environment one   is used to at the office.   Services to locate required facilities and take advantage of them   must also be available on the network.  These range from the basic   "white" and "yellow" pages, providing network locations (addresses)   for users and capabilities, through to distributed data bases and   computing facilities.  Eventually, this conglomeration of computers,   workstations, networks, and other computing resources will become one   gigantic distributed "world computer" with a very large number of   processing nodes all over the world.2.  NETWORK CONNECTIVITY   By network connectivity, we mean the ability to move packets from one   point to another.   Note that an implicit assumption in this paper is that packet   switched networks are the preferred technology for providing a   scientific computer network.  This is due to the ability of such   networks to share the available link resources to provide   interconnection between numerous sites and their ability to   effectively handle the "bursty" computer communication requirement.   Note that this need not mean functional interoperability, since the   endpoints may be using incompatible protocols.  Thus, in this   section, we will be addressing the use of shared links and   interconnected networks to provide a possible path.  In the next   section, the exploitation of these paths to achieve functional   connectivity will be addressed.   In this section, we discuss the need for providing these network   paths to a wide set of users and resources, and the characteristics   of those paths.  As in other sections, this discussion is broken into   two major categories.  The first category are those goals which we   believe to be achievable with currently available technology and   implementations.  The second category are those for which further   research is required.Near Term Objectives   Currently, there are a large number of networks serving the   scientific community, including Arpanet, MFEnet, SPAN, NASnet, and   the NSFnet backbone.  While there is some loose correlation between   the networks and the disciplines they serve, these networks are   organized more based on Federal funding.  Furthermore, while there is   significant interconnectivity between a number of the networks, thereLeiner                                                          [Page 6]

RFC 1017          Requirements for Scientific Research       August 1987   is considerable room for more sharing of these resources.   In the near term, therefore, there are two major requirement areas;   providing for connectivity based on discipline and user community,   and providing for the effective use of adequate networking resources.Discipline Connectivity   Scientists in a particular community/discipline need to have access   to many common resources as well as communicate with each other.  For   example, the quantum physics research community obtains funding from   a number of Federal sources, but carries out its research within the   context of a scientific discourse.  Furthermore, this discourse often   overlaps several disciplines.  Because networks are generally   oriented based on the source of funding, this required connectivity   has in the past been inhibited.  NSFnet is a major step towards   satisfying this requirement, because of its underlying philosophy of   acting as an interconnectivity network between supercomputer centers   and between state, regional, and therefore campus networks.  This   move towards a set of networks that are interconnected, at least at   the packet transport level, must be continued so that a scientist can   obtain connectivity between his/her local computing equipment and the   computing and other resources that are needed, independently of the   source of funds.   Obviously, actual use of those resources will depend on obtaining   access permission from the appropriate controlling organization.  For   example, use of a supercomputer will require permission and some   allocation of computing resources.  The lack of network access should   not, however, be the limiting factor for resource utilization.Communication Resource Sharing   The scientific community is always going to suffer from a lack of   adequate communication bandwidth and connections.  There are   requirements (e.g. graphic animation from supercomputers) that   stretch the capabilities of even the most advanced long-haul   networks.  In addition, as more and more scientists require   connection into networks, the ability to provide those connections on   a network-centric basis will become more and more difficult.   However, the communication links (e.g. leased lines and satellite   channels) providing the underlying topology of the various networks   span in aggregate a very broad range of the scientific community   sites.  If, therefore, the networks could share these links in an   effective manner, two objectives could be achieved:      The need to add links just to support a particular networkLeiner                                                          [Page 7]

RFC 1017          Requirements for Scientific Research       August 1987      topology change would be decreased, and      New user sites could be connected more readily.   Existing technology (namely the DARPA-developed gateway system based   on the Internet Protocol, IP) provides an effective method for   accomplishing this sharing.  By using IP gateways to connect the   various networks, and by arranging for suitable cost-sharing, the   underlying connectivity would be greatly expanded and both of the   above objectives achieved.Expansion of Physical Structure   Unfortunately, the mere interconnectivity of the various networks   does not increase the bandwidth available.  While it may allow for   more effective use of that available bandwidth, a sufficient number   of links with adequate bandwidth must be provided to avoid network   congestion.  This problem has already occurred in the Arpanet, where   the expansion of the use of the network without a concurrent   expansion in the trunking and topology has resulted in congestion and   consequent degradation in performance.   Thus, it is necessary to augment the current physical structure   (links and switches) both by increasing the bandwidth of the current   configuration and by adding additional links and switches where   appropriate.Network Engineering   One of the major deficiencies in the current system of networks is   the lack of overall engineering.  While each of the various networks   generally is well supported, there is woefully little engineering of   the overall system.  As the networks are interconnected into a larger   system, this need will become more severe.  Examples of the areas   where engineering is needed are:   Topology engineering-deciding where links and switches should be   installed or upgraded.  If the interconnection of the networks is   achieved, this will often involve a decision as to which networks   need to be upgraded as well as deciding where in the network those   upgrades should take place.   Connection Engineering-when a user site desires to be connected,   deciding which node of which network is the best for that site,   considering such issues as existing node locations, available   bandwidth, and expected traffic patterns to/from that site.   Operations and Maintenance-monitoring the operation of the overallLeiner                                                          [Page 8]

RFC 1017          Requirements for Scientific Research       August 1987   system and identifying corrective actions when failures occur.Support of Different Types of Service   Several different end user applications are currently in place, and   these put different demands on the underlying structure.  For   example, interactive remote login requires low delay, while file   transfer requires high bandwidth.  It is important in the   installation of additional links and switches that care be given to   providing a mix of link characteristics.  For example, high bandwidth   satellite channels may be appropriate to support broadcast   applications or graphics, while low delay will be required to support   interactive applications.Future Goals   Significant expansion of the underlying transport mechanisms will be   required to support future scientific networking.  These expansions   will be both in size and performance.Bandwidth   Bandwidth requirements are being driven higher by advances in   computer technology as well as the proliferation of that technology.   As high performance graphics workstations work cooperatively with   supercomputers, and as real-time remote robotics and experimental   control become a reality, the bandwidth requirements will continue to   grow.  In addition, as the number of sites on the networks increase,   so will the aggregate bandwidth requirement.  However, at the same   time, the underlying bandwidth capabilities are also increasing.   Satellite bandwidths of tens of megabits are available, and fiber   optics technologies are providing extremely high bandwidths (in the   range of gigabits).  It is therefore essential that the underlying   connectivity take advantage of these advances in communications to   increase the available end-to-end bandwidth.Expressway Routing   As higher levels of internet connectivity occur there will be a new   set of problems related to lowest hop count and lowest delay routing   metrics. The assumed internet connectivity can easily present   situations where the highest speed, lowest delay route between two   nodes on the same net is via a route on another network.  Consider   two sites one either end of the country, but both on the same   multipoint internet, where their network also is gatewayed to some   other network with high speed transcontinental links.  The routing   algorithms must be able to handle these situations gracefully, and   they become of increased importance in handling global type-of-Leiner                                                          [Page 9]

RFC 1017          Requirements for Scientific Research       August 1987   service routing.3.  NETWORK SPECIFICATIONS    To achieve the end-to-end user functions discussed insection 2, it    is not adequate to simply provide the underlying connectivity    described in the previous section.  The network must provide a    certain set of capabilities on an end-to-end basis.  In this    section, we discuss the specifications on the network that are    required.Near Term Specifications   In the near term, the requirements on the networks are two-fold.   First is to provide those functions that will permit full   interoperability, and second the internetwork must address the   additional requirements that arise in the connection of networks,   users, and resources.Interoperability   A first-order requirement for scientific computer networks (and   computer networks in general) is that they be interoperable with each   other, as discussed in the above section on connectivity.  A first   step to accomplish this is to use IP.  The use of IP will allow   individual networks built by differing agencies to combine resources   and minimize cost by avoiding the needless duplication of network   resources and their management.  However, use of IP does not provide   end-to-end interoperability.  There must also be compatibility of   higher level functions and protocols.  At a minimum, while commonly   agreed upon standards (such as the ISO developments) are proceeding,   methods for interoperability between different protocol suites must   be developed.  This would provide interoperability of certain   functions, such as file transfer, electronic mail and remote login.   The emphasis, however, should be on developing agreement within the   scientific community on use of a standard set of protocols.Access Control   The design of the network should include adequate methods for   controlling access to the network by unauthorized personnel.  This   especially includes access to network capabilities that are reachable   via the commercial phone network and public data nets.  For example,   terminal servers that allow users to dial up via commercial phone   lines should have adequate authentication mechanisms in place to   prevent access by unauthorized individuals.  However, it should be   noted that most hosts that are reachable via such networks are also   reachable via other "non-network" means, such as directly dialingLeiner                                                         [Page 10]

RFC 1017          Requirements for Scientific Research       August 1987   over commercial phone lines.  The purpose of network access control   is not to insure isolation of hosts from unauthorized users, and   hosts should not expect the network itself to protect them from   "hackers".Privacy   The network should provide protection of data that traverses it in a   way that is commensurate with the sensitivity of that data.  It is   judged that the scientific requirements for privacy of data traveling   on networks does not warrant a large expenditure of resources in this   area.  However, nothing in the network design should preclude the use   of link level or end-to-end encryption, or other such methods that   can be added at a later time.  An example of this kind of capability   would be use of KG-84A link encryptors on MILNET or the Fig Leaf   DES-based end-to-end encryption box developed by DARPA.Accounting   The network should provide adequate accounting procedures to track   the consumption of network resources.  Accounting of network   resources is also important for the management of the network, and   particularly the management of interconnections with other networks.   Proper use of the accounting database should allow network management   personnel to determine the "flows" of data on the network, and the   identification of bottlenecks in network resources.  This capability   also has secondary value in tracking down intrusions of the network,   and to provide an audit trail if malicious abuse should occur.  In   addition, accounting of higher level network services (such as   terminal serving) should be kept track of for the same reasons.Type of Service Routing   Type of service routing is necessary since not all elements of   network activity require the same resources, and the opportunities   for minimizing use of costly network resources are large.  For   example, interactive traffic such as remote login requires low delay   so the network will not be a bottleneck to the user attempting to do   work.  Yet the bandwidth of interactive traffic can be quite small   compared to the requirements for file transfer and mail service which   are not response time critical.  Without type of service routing,   network resources must sized according to the largest user, and have   characteristics that are pleasing to the most finicky user.  This has   major cost implications for the network design, as high-delay links,   such as satellite links, cannot be used for interactive traffic   despite the significant cost savings they represent over terrestrial   links.  With type of service routing in place in the network   gateways, and proper software in the hosts to make use of suchLeiner                                                         [Page 11]

RFC 1017          Requirements for Scientific Research       August 1987   capabilities, overall network performance can be enhanced, and   sizable cost savings realized.  Since the IP protocol already has   provisions for such routing, such changes to existing implementations   does not require a major change in the underlying protocol   implementations.Administration of Address Space   Local administration of network address space is essential to provide   for prompt addition of hosts to the network, and to minimize the load   on backbone network administrators.  Further, a distributed name to   address translation service also has similar advantages.  The DARPA   Name Domain system currently in use on the Internet is a suitable   implementation of such a name to address translation system.Remote Procedure Call Libraries   In order to provide a standard library interface so that distributed   network utilities can easily communicate with each other in a   standard way, a standard Remote Procedure Call (RPC) library must be   deployed.  The computer industry has lead the research community in   developing RPC implementations, and current implementations tend to   be compatible within the same type of operating system, but not   across operating systems.  Nonetheless, a portable RPC implementation   that can be standardized can provide a substantial boost in present   capability to write operating system independent network utilities.   If a new RPC mechanism is to be designed from scratch, then it must   have enough capabilities to lure implementors away from current   standards.  Otherwise, modification of an existing standard that is   close to the mark in capabilities seems to be in order, with the   cooperation of vendors in the field to assure implementations will   exist for all major operating systems in use on the network.Remote Job Entry (RJE)   The capabilities of standard network RJE implementations are   inadequate, and are implemented prolifically among major operating   systems.  While the notion of RJE evokes memories of dated   technologies such as punch cards, the concept is still valid, and is   favored as a means of interaction with supercomputers by science   users.  All major supercomputer manufacturers support RJE access in   their operating systems, but many do not generalize well into the   Internet domain.  That is, a RJE standard that is designed for 2400   baud modem access from a card reader may not be easily modifiable for   use on the Internet.  Nonetheless, the capability for a network user   to submit a job from a host and have its output delivered on a   printer attached to a different host would be welcomed by most   science users.  Further, having this capability interoperate withLeiner                                                         [Page 12]

RFC 1017          Requirements for Scientific Research       August 1987   existing RJE packages would add a large amount of flexibility to the   whole system.Multiple Virtual Connections   The capability to have multiple network connections open from a   user's workstation to remote network hosts is an invaluable tool that   greatly increases user productivity.  The network design should not   place limits (procedural or otherwise) on this capability.Network Operation and Management Tools   The present state of internet technology requires the use of   personnel who are, in the vernacular of the trade, called network   "wizards," for the proper operation and management of networks.   These people are a scarce resource to begin with, and squandering   them on day to day operational issues detracts from progress in the   more developmental areas of networking.  The cause of this problem is   that a good part of the knowledge for operating and managing a   network has never been written down in any sort of concise fashion,   and the reason for that is because networks of this type in the past   were primarily used as a research tool, not as an operational   resource.  While the usage of these networks has changed, the   technology has not adjusted to the new reality that a wizard may not   be nearby when a problem arises.  To insure that the network can   flexibly expand in the future, new tools must be developed that allow   non-wizards to monitor network performance, determine trouble spots,   and implement repairs or 'work-arounds'.Future Goals   The networks of the future must be able to support transparent access   to distributed resources of a variety of different kinds.  These   resources will include supercomputer facilities, remote observing   facilities, distributed archives and databases, and other network   services.  Access to these resources is to be made widely available   to scientists, other researchers, and support personnel located at   remote sites over a variety of internetted connections.  Different   modes of access must be supported that are consonant with the sorts   of resources that are being accessed, the data bandwidths required   and the type of interaction demanded by the application.   Network protocol enhancements will be required to support this   expansion in functionality; mere increases in bandwidth are not   sufficient.  The number of end nodes to be connected is in the   hundreds of thousands, driven by increasing use of microprocessors   and workstations throughout the community.  Fundamentally different   sorts of services from those now offered are anticipated, and dynamicLeiner                                                         [Page 13]

RFC 1017          Requirements for Scientific Research       August 1987   bandwidth selection and allocation will be required to support the   different access modes.  Large-scale internet connections among   several agency size internets will require new approaches to routing   and naming paradigms.  All of this must be planned so as to   facilitate transition to the ISO/OSI standards as these mature and   robust implementations are placed in service and tuned for   performance.   Several specific areas are identified as being of critical importance   in support of future network requirements, listed in no particular   order:      Standards and Interface Abstractions         As more and different services are made available on these         various networks it will become increasingly important to         identify interface standards and suitable application         abstractions to support remote resource access.  These         abstractions may be applicable at several levels in the         protocol hierarchy and can serve to enhance both applications         functionality and portability.  Examples are transport or         connection layer abstractions that support applications         independence from lower level network realizations or interface         abstractions that provide a data description language that can         handle a full range of abstract data type definitions.         Applications or connection level abstractions can provide means         of bridging across different protocol suites as well as helping         with protocol transition.      OSI Transition and Enhancements         Further evolution of the OSI network protocols and realization         of large-scale networks so that some of the real protocol and         tuning issues can be dealt with must be anticipated.  It is         only when such networks have been created that these issues can         be approached and resolved.  Type-of-service and Expressway         routing and related routing issues must be resolved before a         real transition can be contemplated.  Using the interface         abstraction approach just described will allow definition now         of applications that can transition as the lower layer networks         are implemented.  Applications gateways and relay functions         will be a part of this transition strategy, along with dual         mode gateways and protocol translation layers.      Processor Count Expansion         Increases in the numbers of nodes and host sites and the         expected growth in use of micro-computers, super-microLeiner                                                         [Page 14]

RFC 1017          Requirements for Scientific Research       August 1987         workstations, and other modest cost but high power computing         solutions will drive the development of different network and         interconnect strategies as well as the infrastructure for         managing this increased name space.  Hierarchical name         management (as in domain based naming) and suitable transport         layer realizations will be required to build networks that are         robust and functional in the face of the anticipated         expansions.      Dynamic Binding of Names to Addresses         Increased processor counts and increased usage of portable         units, mobile units and lap-top micros will make dynamic         management of the name/address space a must.  Units must have         fixed designations that can be re-bound to physical addresses         as required or expedient.4.  USER SERVICES   The user services of the network are a key aspect of making the   network directly useful to the scientist.  Without the right user   services, network users separate into artificial subclasses based on   their degree of sophistication in acquiring skill in the use of the   network.  Flexible information dissemination equalizes the   effectiveness of the network for different kinds of users.Near Term Requirements   In the near term, the focus is on providing the services that allow   users to take advantage of the functions that the interconnected   network provides.Directory services   Much of the information necessary in the use of the network is for   directory purposes.  The user needs to access resources available on   the network, and needs to obtain a name or address.White Pages   The network needs to provide mechanisms for looking up names and   addresses of people and hosts on the network.  Flexible searches   should be possible on multiple aspects of the directory listing.   Some of these services are normally transparent to the user/host name   to address translation for example.Leiner                                                         [Page 15]

RFC 1017          Requirements for Scientific Research       August 1987Yellow Pages   Other kinds of information lookup are based on cataloging and   classification of information about resources on the networks.Information Sharing Services      Bulletin Boards         The service of the electronic bulletin board is the one-to-many         analog of the one-to-one service of electronic mail.  A         bulletin board provides a forum for discussion and interchange         of information.  Accessibility is network-wide depending on the         definition of the particular bulletin board.  Currently the         SMTP and UUCP protocols are used in the transport of postings         for many bulletin boards, but any similar electronic mail         transport can be substituted without affecting the underlying         concept.  An effectively open-ended recipient list is specified         as the recipient of a message, which then constitutes a         bulletin board posting.  A convention exists as to what         transport protocols are utilized for a particular set of         bulletin boards.  The user agent used to access the Bulletin         Board may vary from host to host.  Some number of host         resources on the network provide the service of progressively         expanding the symbolic mail address of the Bulletin Board into         its constituent parts, as well as relaying postings as a         service to the network.  Associated with this service is the         maintenance of the lists used in distributing the postings.         This maintenance includes responding to requests from Bulletin         Board readers and host Bulletin Board managers, as well as         drawing the appropriate conclusions from recurring         automatically generated or error messages in response to         distribution attempts.      Community Archiving         Much information can be shared over the network.  At some point         each particular information item reaches the stage where it is         no longer appropriately kept online and accessible.  When         moving a file of information to offline storage, a network can         provide its hosts a considerable economy if information of         interest to several of them need only be stored offline once.         Procedures then exist for querying and retrieving from the set         of offline stored files.      Shared/distributed file system         It should be possible for a user on the network to look at aLeiner                                                         [Page 16]

RFC 1017          Requirements for Scientific Research       August 1987         broadly defined collection of information on the network as one         useful whole.  To this end, standards for accessing files         remotely are necessary.  These standards should include means         for random access to remote files, similar to the generally         employed on a single computer system.      Distributed Databases and Archives         As more scientific disciplines computerize their data archives         and catalogs, mechanisms will have to be provided to support         distributed access to these resources.  Fundamentally new kins         of collaborative research will become possible when such         resources and access mechanisms are widely available.      Resource Sharing Services         In sharing the resources or services available on the network,         certain ancillary services are needed depending on the         resource.Access Control   Identification and authorization is needed for individuals, hosts or   subnetworks permitted to make use of a resource available via the   network.  There should be consistency of procedure for obtaining and   utilizing permission for use of shared resources.  The identification   scheme used for access to the network should be available for use by   resources as well.  In some cases, this will serve as sufficient   access control, and in other cases it will be a useful adjunct to   resource-specific controls.  The information on the current network   location of the user should be available along with information on   user identification to permit added flexibility for resources.  For   example, it should be possible to verify that an access attempt is   coming from within a state.  A state agency might then grant public   access to its services only for users within the state.  Attributes   of individuals should be codifiable within the access control   database, for example membership in a given professional society.Privacy   Users of a resource have a right to expect that they have control   over the release of the information they generate.  Resources should   allow classifying information according to degree of access, i.e.   none, access to read, access according to criteria specified in the   data itself, ability to change or add information.  The full range of   identification information described under access control should be   available to the user when specifying access.  Access could be   granted to all fellow members of a professional society, for example.Leiner                                                         [Page 17]

RFC 1017          Requirements for Scientific Research       August 1987Accounting   To permit auditing of usage, accounting information should be   provided for those resources for which it is deemed necessary.  This   would include identity of the user of the resource and the   corresponding volume of resource components.Legalities of Interagency Research Internet   To make the multiply-sponsored internetwork feasible, the federal   budget will have to recognize that some usage outside a particular   budget category may occur.  This will permit the cross-utilization of   agency funded resources.  For example, NSFnet researchers would be   able to access supercomputers over NASnet.  In return for this, the   total cost to the government will be significantly reduced because of   the benefits of sharing network and other resources, rather than   duplicating them.Standards   In order for the networking needs of scientific computing to be met,   new standards are going to evolve.  It is important that they be   tested under actual use conditions, and that feedback be used to   refine them.  Since the standards for scientific communication and   networking are to be experimented with, they are more dynamic than   those in other electronic communication fields.  It is critical that   the resources of the network be expended to promulgate experimental   standards and maximize the range of the community utilizing them.  To   this end, the sharing of results of the testing is important.User-oriented Documentation   The functionality of the network should be available widely without   the costly need to refer requests to experts for formulation.  A   basic information facility in the network should therefore be   developed.  The network should be self-documenting via online help   files, interactive tutorials, and good design.  In addition, concise,   well-indexed and complete printed documentation should be available.Future Goals   The goal for the future should be to provide the advanced user   services that allow full advantage to be taken of the interconnection   of users, computing resources, data bases, and experimental   facilities.  One major goal would be the creation of a national   knowledge bank.  Such a knowledge bank would capture and organize   computer-based knowledge in various scientific fields that is   currently available only in written/printed form, or in the minds ofLeiner                                                         [Page 18]

RFC 1017          Requirements for Scientific Research       August 1987   experts or experienced workers in the field.  This knowledge would be   stored in knowledge banks which will be accessible over the network   to individual researchers and their programs.  The result will be a   codification of scientific understanding and technical know-how in a   series of knowledge based systems which would become increasingly   capable over time.CONCLUSION   In this paper, we have tried to describe the functions required of   the interconnected national network to support scientific research.   These functions range from basic connectivity through to the   provision for powerful distributed user services.   Many of the goals described in this paper are achievable with current   technology.  They require coordination of the various networking   activities, agreement to share costs and technologies, and agreement   to use common protocols and standards in the provision of those   functions.  Other goals require further research, where the   coordination of the efforts and sharing of results will be key to   making those results available to the scientific user.   For these reasons, we welcome the initiative represented by this   workshop to have the government agencies join forces in providing the   best network facilities possible in support of scientific research.APPENDIX                Internet Task Force on Scientific Computing             Rick Adrion     University of Massachusetts             Ron Bailey      NASA Ames Research Center             Rick Bogart     Stanford University             Bob Brown       RIACS             Dave Farber     University of Delaware             Alan Katz       USC Information Science Institute             Jim Leighton    Lawrence Livermore Laboratories             Keith Lantz     Stanford University             Barry Leiner    (chair) RIACS             Milo Medin      NASA Ames Research Center             Mike Muuss      US Army Ballistics Research Laboratory             Harvey Newman   California Institute of Technology             David Roode     Intellicorp             Ari Ollikainen  General Electric             Peter Shames    Space Telescope Science Institute             Phil Scherrer   Stanford UniversityLeiner                                                         [Page 19]