Network Working Group                          National Research Council
Request for Comments: 939
                                                          February 1985

                          Executive Summary
                         of the NRC Report on
                       Transport Protocols for
                        Department of Defense
                            Data Networks


STATUS OF THIS MEMO

  This RFC is distributed for information only.  This RFC does not
  establish any policy for the DARPA research community or the DDN
  operational community.  Distribution of this memo is unlimited.

INTRODUCTION

  This RFC reproduces the material from the "front pages" of the
  National Research Council report resulting from a study of the DOD
  Internet Protocol (IP) and Transmission Control Protocol (TCP) in
  comparison with the ISO Internet Protocol (ISO-IP) and Transport
  Protocol level 4 (TP-4).  The point of this RFC is to make the text
  of the Executive Summary widely available in a timely way.  The order
  of presentation has been altered, and the pagination changed.

  The title of the full report is:



                       Transport Protocols for
                        Department of Defense
                            Data Networks

                 Report to the Department of Defense
                 and the National Bureau of Standards

        Committee on Computer-Computer Communication Protocols

  Board on Telecommunications and Computer Applications Commission on
                  Engineering and Technical Systems
                      National Research Council

                        National Academy Press
                   Washington, D.C.  February 1985







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                               OVERVIEW

  The project that is the subject of this report was approved by the
  Governing Board on the National Research Council, whose members are
  drawn from the councils of the National Academy of Sciences, the
  National Academy of Engineering, and the Institute of Medicine.  The
  members of the committee responsible for the report were chosen for
  their special competences and with regard for appropriate balance.

  This report has been reviewed by a group other than the authors,
  according to procedures approved by a Report Review Committee
  consisting of members of the National Academy of Sciences, the
  National Academy of Engineering, and the Institute of Medicine.

  The National Research Council was established by the National Academy
  of Sciences in 1916 to associate the broad community of science and
  technology with the Academy's purposes of furthering knowledge and of
  advising the federal government.  The Council operates in accordance
  with general policies determined by the Academy under the authority
  of its congressional charter of 1863, which establishes the Academy
  as a private, nonprofit, self-governing membership corporation.  The
  Council has become the principal operating agency of both the
  National Academy of Sciences and the National Academy of Engineering
  in the conduct of their services to the government, the public, and
  the scientific and engineering communities.  It is administered
  jointly by both Academies and the Institute of Medicine.  The
  National Academy of Engineering and the Institute of Medicine were
  established in 1964 and 1970, respectively, under the charter of the
  National Academy of Sciences.

  This is a report of work supported by Contract No. DCA-83-C-0051
  between the U.S. Defense Communications Agency and the National
  Academy of Sciences, underwritten jointly by the Department of
  Defense and the National Bureau of Standards.

  Copies of the full report are available from:

     Board on Telecommunications and Computer Applications Commission
     on Engineering and Technical Systems
     National Research Council
     2101 Constitution Avenue, N.W.
     Washington, D.C. 20418







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                               PREFACE

  This is the final report of the National Research Council Committee
  on Computer-Computer Communication Protocols.  The committee was
  established in May l983 at the request of the Department of Defense
  (DOD) and the National Bureau of Standards (NBS), Department of
  Commerce, to develop recommendations and guidelines for resolving
  differences between the two agencies on a data communications
  transport protocol standard.

  Computer-based information and transaction-processing systems are
  basic tools in modern industry and government.  Over the past several
  years there has been a growing demand to transfer and exchange
  digitized data in these systems quickly and accurately.  This demand
  for data transfer and exchange has been both among the terminals and
  computers within an organization and among those in different
  organizations.

  Rapid electronic transport of digitized data requires electronic
  communication links that tie the elements together.  These links are
  established, organized, and maintained by means of a layered series
  of procedures performing the many functions inherent in the
  communications process.  The successful movement of digitized data
  depends upon the participants using identical or compatible
  procedures, or protocols.

  The DOD and NBS have each developed and promulgated a transport
  protocol as standard.  The two protocols, however, are dissimilar and
  incompatible.  The committee was called to resolve the differences
  between these protocols.

  The committee held its first meeting in August l983 at the National
  Research Council in Washington, D.C.  Following this two-day meeting
  the committee held five more two-day meetings, a three-day meeting,
  and a one-week workshop.

  The committee was briefed by personnel from both agencies.  In
  addition, the committee heard from Jon Postel, University of Southern
  California's Information Sciences Institute; Dave Oran, Digital
  Equipment Corporation; Vinton Cerf, MCI; David Wood, The Mitre
  Corporation; Clair Miller, Honeywell, and Robert Follett, IBM,
  representing the Computer and Business Equipment Manufacturer's
  Association; and John Newman, Ultimate Corporation.  In most cases
  the briefings were followed by discussion.

  The committee wishes to thank  Philip Selvaggi of the Department of
  Defense and Robert Blanc of the NBS, Institute of Computer Sciences


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  and Technology, for their cooperation as their agency's liaison
  representatives to the committee.  The committee appreciates the
  contributions and support of Richard B. Marsten, Executive Director
  of the Board on Telecommunications -- Computer Applications (BOTCAP),
  and Jerome D. Rosenberg, BOTCAP Senior Staff Officer and the
  committee Study Director.  We also wish to thank Lois A. Leak for her
  expert administrative and secretarial support.










































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                          EXECUTIVE SUMMARY

  Computer communication networks have become a very important part of
  military and commercial operations.  Indeed, the nation is becoming
  dependent upon their efficiency and reliability, and the recent
  proliferation of networks and their widespread use have emphasized
  the importance of developing uniform conventions, or protocols, for
  communication between computer systems.  The Department of Defense
  (DOD) and the National Bureau of Standards (NBS) have been actively
  engaged in activities related to protocol standardization.  This
  report is concerned primarily with recommendations on protocol
  standardization within the Department of Defense.

  Department of Defense's Transmission Protocol

     The DOD's Defense Advanced Research Projects Agency (DARPA) has
     been conducting and supporting research on computer networks for
     over fifteen years (1).  These efforts led to the development of
     modern packet-switched network design concepts.  Transmission
     between computers is generally accomplished by packet switching
     using strict protocols for the control and exchange of messages.
     The Advanced Research Projects Agency network (ARPANET),
     implemented in the early 1970s, provided a testing ground for
     research on communications protocols.  In 1978, after four years
     of development, the DOD promulgated versions of its Transmission
     Control Protocol (TCP) and an Internet Protocol (IP) and mandated
     their use as standards within the DOD.  TCP is now widely used and
     accepted.  These protocols meet the unique operational and
     functional requirements of the DOD, and any changes in the
     protocols are viewed with some trepidation by members of the
     department.  DOD representatives have stated that standardizing
     TCP greatly increased the momentum within the DOD toward
     establishing interoperability between networks within the DOD.

  International Standards Organization's Transport Protocol

     The NBS Institute for Computer Sciences and Technology (ICST), in
     cooperation with the DOD, many industrial firms, and the
     International Standards Organization (ISO), has developed a new
     international standard

     Transport Protocol (TP-4) and a new Internetwork Protocol (2).
     These protocols will soon be available as commercial products.
     Although in part derived from TCP, the new protocols are not
     compatible with TCP (3).  The U.S. standards organizations are




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     supporting TP-4 in international operations, and the Department of
     Commerce is proposing TP-4 as a Federal Information Processing
     Standard (FIPS) for use by all federal agencies.

  DOD OPERATIONAL AND TECHNICAL NEEDS

     The DOD has unique needs that could be affected by the Transport
     and Internet Protocol layers.  Although all data networks must
     have some of these capabilities, the DOD's needs for operational
     readiness, mobilization, and war-fighting capabilities are
     extreme.  These needs include the following:

        Survivability--Some networks must function, albeit at reduced
        performance, after many nodes and links have been destroyed.

        Security--Traffic patterns and data must be selectively
        protected through encryption, access control, auditing, and
        routing.

        Precedence--Systems should adjust the quality of service on the
        basis of priority of use; this includes a capability to preempt
        services in cases of very high priority.

        Robustness--The system must not fail or suffer much loss of
        capability because of unpredicted situations, unexpected loads,
        or misuse.  An international crisis is the strongest test of
        robustness, since the system must operate immediately and with
        virtually full performance when an international situation
        flares up unexpectedly.

        Availability--Elements of the system needed for operational
        readiness or fighting must be continuously available.

        Interoperability--Different elements of the Department must be
        able to "talk" to one another, often in unpredicted ways
        between parties that had not planned to interoperate.

     These operational needs reflect themselves into five technical or
     managerial needs:

        1.   Functional and operational specifications (that is, will
             the protocol designs meet the operational needs?);

        2.   Maximum interoperability;

        3.   Minimum procurement, development, and support costs;



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        4.   Ease of transition to new protocols; and

        5.   Manageability and responsiveness to changing DOD
             requirements.

     These are the criteria against which DOD options for using the ISO
     transport and internet protocols should be evaluated.

     Interoperability is a very important DOD need.  Ideally, DOD
     networks would permit operators at any terminal to access or be
     accessed by applications in any computer.  This would provide more
     network power for users, integration of independently developed
     systems, better use of resources, and increased survivability.  To
     increase interoperability, the Office of the Secretary of Defense
     has mandated the use of TCP for the Defense Communication System's
     Defense Data Network (DDN), unless waivers are granted.  In
     addition, the Defense Communication Agency (DCA) is establishing
     standards for three higher-level "utility" protocols for file
     transfer, terminal access, and electronic mail.  Partly as a
     result of these actions, it has become clear that there is growing
     momentum toward accepting interoperability and a recognition that
     it is an important operational need.

     It is very important, however, to recognize that functional
     interoperability is only achieved with full generality when two
     communication nodes can interoperate at all protocol levels.  For
     the DOD the relevant levels are as follows:

        1.   Internet, using IP;

        2.   Transport, using TCP;

        3.   Utility, using file, terminal, or mail protocols; and

        4.   Specific applications that use the above protocols for
             their particular purpose.

     Accordingly, if a network is developed using one transport
     protocol, it would generally not be able to interoperate
     functionally with other networks using the same transport protocol
     unless both networks were also using the higher-level utility and
     application protocols.  In evaluating whether or not to convert to
     TP-4 and in developing a transition plan, the following factors
     must be considered:

        The DOD contains numerous communities of interest whose
        principal need is to interoperate within their own members,


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        independently. Such communities generally have a specific,
        well-defined mission. The DOD Intelligence Information System
        (DODIIS) and the World Wide Military Command and Control System
        (WWMCCS) are examples. Interoperability is needed primarily
        between the higher layer applications programs initially unique
        to each community of interest.

        There are many different kinds of operations needed between
        communities of interest.  Examples of such operations are
        headquarters' need for access to several subordinate
        communities and the communities' need for some minimum
        functional interoperability with each other (such as mail
        exchange).

        The need for functional interoperability can arise,
        unexpectedly and urgently, at a time of crisis or when improved
        management opportunities are discovered.  Widespread
        standardization of TP-4 and higher-level protocols can readily
        help to achieve these needs.  Often, special development of
        additional applications that cost time and money will be
        necessary.

        The DOD needs functional interoperability with many important
        external agencies that are committed to ISO standards:  The
        North Atlantic Treaty Organization (NATO), some intelligence
        and security agencies, and other parts of the federal
        government.

        The same objectives that have prompted the use of standardized
        protocols at higher-level headquarters will lead to their use
        by tactical groups in the field.

  SOME COMPARISONS

     A detailed comparison of the DOD Transmission Control Protocol and
     the ISO Transport Protocol indicates they are functionally
     equivalent and provide essentially similar services.  Because it
     is clear that a great deal of care and experience in protocol
     development have gone into generating the specifications for TP-4,
     the committee is confident that TP-4 will meet military
     requirements.

     Although there are differences between the two protocols, they do
     not compromise DOD requirements.  And, although in several areas,
     including the data transfer interface, flow control, connection
     establishment, and out-of-band, services are provided in different
     ways by the two protocols, neither seems intrinsically superior.


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     Thus, while existing applications may need to be modified somewhat
     if moved from TCP to TP-4, new applications can be written to use
     either protocol with a similar level of effort.

     The TCP and TP-4 protocols are sufficiently equivalent in their
     security-related properties in that there are no significant
     technical points favoring the use of one over the other.

     While TCP currently has the edge in maturity of implementation,
     TP-4 is gaining rapidly due to the worldwide support for and
     acceptance of the Open System Interconnection (OSI) international
     standards.  Experimental TCP implementations were completed in
     1974 at Stanford University and BBN Communications Corporation.
     Between 1974 and 1982 a large number of implementations were
     produced.  The Defense Advanced Research Projects Agency (ARPA)
     network switched to a complete use of TCP in January 1983.
     Operations have been satisfactory and its use is growing.  A
     number of TCP implementations are also in commercial use in
     various private networks.

     In contrast, TP-4 has not yet been implemented in any large
     operational system.  It has been tested experimentally, however,
     and has received endorsement by many commercial vendors worldwide.
     In addition, substantial portions of TP-4 have been demonstrated
     at the National Computer Conference in July 1984.

     The Internet Protocol (IP) part of the standards is not believed
     to be a problem.  The ISO IP is not as far along as TP-4, but it
     is much less complex.  The ISO IP, based very strongly on the DOD
     IP, became a draft international standard in April 1984.

     The rapidity of the progress in ISO and the results achieved over
     the past two years have surprised even the supporters of
     international standards. The reasons for this progress are
     twofold:  strong market demands stemming from the growing
     integration of communications and data processing and the progress
     in networking technology over the past years as the result of ARPA
     and commercial developments.

     Although the DOD networks have been a model upon which the ISO
     transport standards have been built, the rest of the world is
     adopting TP-4. Because the DOD represents a small fraction of the
     market and because the United States supports the ISO standard, it
     is not realistic to hope that TP-4 can be altered to conform with
     TCP.  This raises the question as to what action should be taken
     by the DOD with respect to the ISO standard.



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  SOME ECONOMIC CONSIDERATIONS

     The DOD has a large and growing commitment in operational TCP
     networks, and this will increase by 50 to 100 percent in the next
     eighteen months.  This rate of investment will probably continue
     for the next five years for new systems and the upgrading of
     current ones.  The current Military Network (MILNET) and Movement
     Information Network (MINET) systems are expanding and will shortly
     be combined.  The Strategic Air Command Digital Information
     Network (SACDIN) and DODIIS are undergoing major upgrading.  When
     these changes are completed, there are plans to upgrade the WWMCCS
     Intercomputer Network (WIN) and to add separate SECRET and TOP
     SECRET networks.  There are plans to combine these six networks in
     the late 1980s, and they will become interoperable and multilevel
     secure using an advanced technology now under development.  If
     these plans are implemented on schedule, a delay of several years
     in moving to TP-4 would mean that the DOD networks in the late
     1980s would be virtually all TCP-based. Subsequent conversion to
     international standards would be very expensive if hastily
     attempted in order to maintain established DOD interoperability
     and gain interoperability with a large body of users.

     As the Department of Defense policy recognizes, there are
     significant advantages in using commercial vendor products if they
     meet the department's operational needs.  The major advantages are
     as follows:

        Costs to the DOD for development, production, and maintenance
        are significantly lower because (1) vendors spread the cost
        over a much larger user base, (2) commercial vendors are
        generally more efficient in their operations, and (3) vendors
        look for ways to improve their product to meet competition.

        The department generally gets more effective products because
        vendors integrate the protocol functions into their entire
        software and hardware product line.  Thus the DOD may be able
        eventually to use commercial software products that are built
        on top of, and thereby take advantage of, the transport
        protocols.

        By depending on industry to manage the development and
        maintenance of products, the department can use its scarce
        management and technical resources on activities unique to its
        mission.

     Because the costs of transport and internet protocol development
     and maintenance are so intertwined with other factors, it is


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     impossible to give a precise estimate of the savings that would be
     achieved by using commercial products.  Savings will vary in
     individual cases.  The marginal savings should range from 30 to 80
     percent.

  RECOMMENDATIONS

     The ISO protocols are now well specified but will not generally be
     commercially available for many months.  Nevertheless, this
     committee believes that the principles on which they are based are
     well-established, and the protocols can be made to satisfy fully
     DOD's needs.  The committee recommends that the DOD move toward
     adoption of TP-4 as costandard with TCP and toward exclusive use
     of TP-4.

     Transition to the use of the ISO standards, however, must be
     managed in a manner that will maintain DOD's operational
     capabilities and minimize risks.  The timing of the transition is,
     therefore, a major concern.

     Descriptions of two options that take this requirement into
     account follow.  A majority of the committee recommends the first
     option, while a minority favors the second.  A third option--to
     defer action--is also described but not recommended.

     Option 1

        The first option is for the DOD to immediately modify its
        current transport policy statement to specify TP-4 as a
        costandard along with TCP.  In addition, the DOD would develop
        a military specification for TP-4 that would also cover DOD
        requirements for discretionary options allowed under the NBS
        protocol specifications.  Requests for proposals (RFPs) for new
        networks or major upgrades of existing networks would specify
        TP-4 as the preferred protocol.  Contracts for TP-4 systems
        would be awarded only to contractors providing commercial
        products, except for unique cases.

        Existing networks that use TCP and new networks firmly
        committed to the use of TCP-based systems could continue to
        acquire implementations of TCP.  The DOD should carefully
        review each case, however, to see whether it would be
        advantageous to delay or modify some of these acquisitions in
        order to use commercial TP-4 products.  For each community of
        users it should be decided when it is operationally or




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        economically most advantageous to replace its current or
        planned systems in order to conform to ISO standards without
        excessively compromising continued operations.

        United States government test facilities would be developed to
        enable validation of TP-4 products (4).  The Department of
        Defense would either require that products be validated using
        these test facilities or that they be certified by the vendor.
        The test facilities could also be used to isolate multivendor
        protocol compatibility problems.  The existing NBS validation
        tools should be used as the base for the DOD test facilities.

        Because under this option networks based on both TCP and TP-4
        would coexist for some time, several capabilities that
        facilitate interoperability among networks would need to be
        developed.  The Department of Defense generally will not find
        them commercially available.  Examples are gateways among
        networks or specialized hosts that provide services such as
        electronic mail.  The department would need to initiate or
        modify development programs to provide these capabilities, and
        a test and demonstration network would be required.

     Option 2

        Under Option 2 the Department of Defense would immediately
        announce its intention to adopt TP-4 as a transport protocol
        costandard with TCP after a satisfactory demonstration of its
        suitability for use in military networks.  A final commitment
        would be deferred until the demonstration has been evaluated
        and TP-4 is commercially available.

        The demonstration should take at most eighteen months and
        should involve development of TP-4 implementations and their
        installation.  This option differs from Option 1 primarily in
        postponing the adoption of a TP-4 standard and, consequently,
        the issuance of RFPs based on TP-4 until successful completion
        of a demonstration.  The department, however, should proceed
        with those provisions of Option 1 that may be completed in
        parallel with the demonstration.  Early issuance of a TP-4
        military specification, development of validation procedures,
        and implementation of means for interoperability would be
        particularly important in this regard.







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     Option 3

        Under the third option the DOD would continue using TCP as the
        accepted transport standard and defer any decision on the use
        of TP-4 indefinitely.  The department would be expected to stay
        well informed on the development and use of the new protocol in
        the commercial and international arena and, with the National
        Bureau of Standards, work on means to transfer data between the
        two protocol systems.  Testing and evaluation of TP-4 standards
        by NBS would continue.  The DOD might eventually accommodate
        both protocol systems in an evolutionary conversion to TP-4.

     Comparison of Options

        The committee believes that all three options equally satisfy
        the functional objectives of the DOD, including matters of
        security.  It believes the two protocols are sufficiently
        similar and no significant differences in performance are to be
        expected if the chosen protocol implementation is of equal
        quality and is optimized for the given environment.

        The primary motivation for recommending Option 1 is to obtain
        the benefits of standard commercial products in the
        communication protocol area at an early date.  Benefits include
        smaller development, procurement, and support costs; more
        timely updates; and a wider product availability. By
        immediately committing to TP-4 as a costandard for new systems,
        Option 1 minimizes the number of systems that have to be
        converted eventually from TCP.  The ability to manage the
        transition is better than with Option 2 since the number of
        systems changed would be smaller and the time duration of mixed
        TCP and TP-4 operation would be shorter. Interoperability with
        external systems (NATO, government, commercial), which
        presumably will also use TP-4, would be brought about more
        quickly. Option 1 involves greater risk, however, since it
        commits to a new approach without as complete a demonstration
        of its viability.

        As with Option 1, a primary benefit of following Option 2 would
        be obtaining the use of standard commercial products.  Unit
        procurement costs probably would be lower than with Option 1
        because the commercial market for TP-4 will have expanded
        somewhat by the time DOD would begin to buy TP-4 products.
        Risk is smaller, compared to Option 1, because testing and
        demonstration of the suitability for military use will have
        preceded the commitment to the ISO protocols.  Transition and
        support costs would be higher than for Option 1, however,


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        because more networks and systems would already have been
        implemented with TCP.  Also this is perhaps the most difficult
        option to manage since the largest number of system conversions
        and the longest interval of mixed TCP and TP-4 operations would
        occur.  In addition, interoperability with external networks
        through standardization would be delayed.

        The principal benefit of exercising Option 3 would be the
        elimination of transition cost and the risk of faulty system
        behavior and delay.  It would allow the most rapid achievement
        of full internal interoperability among DOD systems.
        Manageability should be good because only one set of protocols
        would be in use (one with which the DOD already has much
        experience), and because the DOD would be in complete control
        of system evolution. Procurement costs for TCP systems would
        remain high compared with standard ISO protocol products,
        however, and availability of implementations for new systems
        and releases would remain limited.  External interoperability
        with non-DOD systems would be limited and inefficient.

        In summary, Option 1 provides the most rapid path toward the
        use of commercial products and interoperability with external
        systems.  Option 2 reduces the risk but involves somewhat
        greater delay and expense.  Option 3 involves the least risk
        and provides the quickest route to interoperability within the
        Defense Department at the least short-term cost.  These are,
        however, accompanied by penalties of incompatibility with NATO
        and other external systems and higher life-cycle costs.

  NOTES:

     (1)  The Advanced Research Projects Agency (ARPA) was reorganized
          and became the Defense Advanced Research Projects Agency
          (DARPA) in 1973.

     (2)  The ISO Transport Protocol and ISO Internetwork Protocol
          became Draft International Standards in September 1983 and
          April 1984, respectively. Commercial vendors normally
          consider Draft International Standards to be ready for
          implementation.

     (3)  Except where noted, the abbreviation TCP generally refers to
          both the DOD's Transmission Control Protocol and its Internet
          Protocol.  Similarly, the abbreviation TP-4 refers to both
          the ISO Transport Protocol class 4 and its Internetwork
          Protocol.  (Transport Protocol classes 0 to 3 are used for
          special purposes not related to those of this study.)


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     (4)  Validation means a systematic and thorough state-of-the-art
          testing of the products to assure that all technical
          specifications are being achieved.














































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                     CONTENTS OF THE FULL REPORT

  PREFACE .........................................................  ix

  EXECUTIVE SUMMARY ...............................................  xi

  I     Introduction ...............................................  1

  II    Review of NBS and DOD Objectives ...........................  3

  III   Comparison of DOD and ISO Protocols .......................  13

  IV    Status of DOD and ISO Protocol
        Implementations and Specifications .......................   25

  V     Markets ...................................................  31

  VI    Development of Standard Commercial versus
        Special Commercial Products ...............................  39

  VII   Responsiveness of International Standards
        Process to Change .........................................  43

  VIII  Options for DOD and NBS ...................................  45

  IX    Cost Comparison of Options ...............................   47

  X     Evaluation of Options .....................................  53

  XI    Recommendations ...........................................  61



















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         BOARD ON TELECOMMUNICATIONS -- COMPUTER APPLICATIONS
        COMMITTEE ON COMPUTER-COMPUTER COMMUNICATION PROTOCOLS

  Chairman

     C. CHAPIN CUTLER, Professor of Applied Physics, Stanford
     University, Stanford, California

  Members

     HERBERT D. BENINGTON, Technical Director, System Development
     Corporation, McLean, Virginia

     DONALD L. BOYD, Director, Honeywell Corporate Computer Sciences
     Center, Honeywell Corporate Technology Center, Bloomington,
     Minnesota

     DAVID J. FARBER, Professor of Electrical Engineering and Professor
     of Computer Science, Department of Electrical Engineering,
     University of Delaware, Newark, Delaware

     LAWRENCE H. LANDWEBER, Professor, Computer Sciences Department,
     University of Wisconsin, Madison, Wisconsin

     ANTHONY G. LAUCK, Manager, Distributed Systems Architecture and
     Advanced Development, Digital Equipment Corporation, Tewksbury,
     Massachusetts

     KEITH A. LUCKE, General Manager of Control Data Technical
     Standards, Control Data Corporation, Minneapolis, Minnesota

     MISCHA SCHWARTZ, Professor of Electrical Engineering and Computer
     Science, Columbia University, New York, New York

     ROBERT F. STEEN, Director of Architecture, Communication Products
     Division IBM Corporation, Research Triangle Park, North Carolina

     CARL A. SUNSHINE, Principal Engineer, Sytek, Incorporated, Los
     Angeles Operation, Culver City, California

     DANIEL J. FINK, (Ex-officio), President, D.J. Fink Associates,
     Inc., Arlington, Virginia

     JAMES L. FLANAGAN, (CETS LIAISON MEMBER), Head, Acoustics Research
     Department, AT&T Bell Laboratories, Murray Hill, New Jersey




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  Staff

     RICHARD B. MARSTEN, Executive Director
     JEROME D. ROSENBERG, Senior Staff Officer and Study Director
     LOIS A. LEAK, Administrative Secretary












































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RFC 939                                                    February 1985
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           COMMISSION ON ENGINEERING AND TECHNICAL SYSTEMS
         BOARD ON TELECOMMUNICATIONS -- COMPUTER APPLICATIONS

  Chairman

     DANIEL J. FINK, President, D.J. Fink Associates, Inc., Arlington,
     Virginia

  Past Chairman

     BROCKWAY MCMILLAN, Vice President (Retired), Bell Laboratories,
     Sedgwick, Maine

  Members

     ARTHUR G. ANDERSON, Vice President (Retired), IBM Corporation, San
     Jose, California

     DANIEL BELL, Henry Ford II Professor of Social Sciences,
     Department of Sociology, Harvard University, Cambridge,
     Massachusetts

     HERBERT D. BENINGTON, Technical Director, System Development
     Corporation, McLean, Virginia

     ELWYN R. BERLEKAMP, Professor of Mathematics, Department of
     Mathematics, University of California, Berkeley, California

     ANTHONY J. DEMARIA, Assistant Director of Research for Electronics
     and Electro-Optics Technology, United Technologies Research
     Center, East Hartford, Connecticut

     GERALD P. DINNEEN, Vice President, Science and Technology,
     Honeywell Incorporated, Minneapolis, Minnesota

     GEORGE GERBNER, Professor and Dean, The Annenberg School of
     Communications, University of Pennsylvania, Philadelphia,
     Pennsylvania

     ANNE P. JONES, Partner, Sutherland, Asbill and Brennan,
     Washington, D.C.

     ADRIAN M. MCDONOUGH, Professor of Management and Decision Sciences
     (Retired), The Wharton School, University of Pennsylvania,
     Havertown, Pennsylvania




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     WILBUR L. PRITCHARD, President, Satellite Systems Engineering,
     Inc., Bethesda, Maryland

     MICHAEL B. PURSLEY, Professor of Electrical Engineering,
     University of Illinois, Urbana, Illinois

     IVAN SELIN, Chairman of the Board, American Management Systems,
     Inc., Arlington, Virginia

     MISCHA SCHWARTZ, Professor of Electrical Engineering and Computer
     Science, Columbia University, New York, New York

     ERIC E. SUMNER, Vice President, Operations System and Network
     Planning, AT&T Bell Laboratories, Holmdel, New Jersey

     KEITH W. UNCAPHER, Executive Director, USC-Information Sciences
     Institute Associate Dean, School of Engineering, University of
     Southern California, Marina del Rey, California

     JAMES L. FLANAGAN, (CETS LIAISON MEMBER), Head, Acoustics Research
     Department, AT&T Bell Laboratories, Murray Hill, New Jersey

  Staff

     Richard B. Marsten, Executive Director
     Jerome D. Rosenberg, Senior Staff Officer
     Karen Laughlin, Administrative Coordinator
     Carmen A. Ruby, Administrative Assistant
     Lois A. Leak, Administrative Secretary




















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