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

                           <span class="h1">Executive Summary</span>
                          <span class="h1">of the NRC Report on</span>
                        <span class="h1">Transport Protocols for</span>
                         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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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.)


<span class="grey">National Research Council                                      [Page 14]</span></pre>
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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
Executive Summary of the NRC Report Transport on Protocols


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














































<span class="grey">National Research Council                                      [Page 15]</span></pre>
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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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                      CONTENTS OF THE FULL REPORT

   PREFACE .........................................................  <a href="#page-ix">ix</a>

   EXECUTIVE SUMMARY ...............................................  <a href="#page-xi">xi</a>

   <a href="#appendix-I">I</a>     Introduction ...............................................  <a href="#page-1">1</a>

   II    Review of NBS and DOD Objectives ...........................  <a href="#page-3">3</a>

   III   Comparison of DOD and ISO Protocols .......................  <a href="#page-13">13</a>

   IV    Status of DOD and ISO Protocol
         Implementations and Specifications .......................   <a href="#page-25">25</a>

   <a href="#appendix-V">V</a>     Markets ...................................................  <a href="#page-31">31</a>

   VI    Development of Standard Commercial versus
         Special Commercial Products ...............................  <a href="#page-39">39</a>

   VII   Responsiveness of International Standards
         Process to Change .........................................  <a href="#page-43">43</a>

   VIII  Options for DOD and NBS ...................................  <a href="#page-45">45</a>

   IX    Cost Comparison of Options ...............................   <a href="#page-47">47</a>

   <a href="#appendix-X">X</a>     Evaluation of Options .....................................  <a href="#page-53">53</a>

   XI    Recommendations ...........................................  <a href="#page-61">61</a>



















<span class="grey">National Research Council                                      [Page 16]</span></pre>
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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
Executive Summary of the NRC Report Transport on Protocols


          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&amp;T Bell Laboratories, Murray Hill, New Jersey




<span class="grey">National Research Council                                      [Page 17]</span></pre>
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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
Executive Summary of the NRC Report Transport on Protocols


   Staff

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












































<span class="grey">National Research Council                                      [Page 18]</span></pre>
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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
Executive Summary of the NRC Report Transport on Protocols


            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




<span class="grey">National Research Council                                      [Page 19]</span></pre>
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<span class="grey"><a href="./rfc939">RFC 939</a>                                                    February 1985</span>
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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&amp;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&amp;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




















National Research Council                                      [Page 20]
</pre>