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diff --git a/doc/rfc/rfc1017.txt b/doc/rfc/rfc1017.txt new file mode 100644 index 0000000..9aad149 --- /dev/null +++ b/doc/rfc/rfc1017.txt @@ -0,0 +1,1067 @@ + + + + + + +Network Working Group Barry M. Leiner +Request for Comments: 1017 RIACS + August 1987 + + Network Requirements for Scientific Research + + Internet Task Force on Scientific Computing + +STATUS 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. This + + + +Leiner [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 be + + + +Leiner [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, there + + + +Leiner [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 network + + + +Leiner [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 overall + + + +Leiner [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 in section 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 dialing + + + +Leiner [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 such + + + +Leiner [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 with + + + +Leiner [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 dynamic + + + +Leiner [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-micro + + + +Leiner [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 1987 + + +Yellow 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 a + + + +Leiner [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 1987 + + +Accounting + + 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 of + + + +Leiner [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 University + + + + +Leiner [Page 19] +
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