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rfc:rfc1017

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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