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RFC 369 - Evaluation of ARPANET services January-March, 1972


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Network Working Group                                         J. Pickens
Request for Comments: 369               UCSB COMPUTER SYSTEMS LABORATORY
NIC: 6801                                                   25 July 1972

                     EVALUATION OF ARPANET SERVICES
                      January through March, 1972

ABSTRACT

   RFC #302, Exercising the ARPANET, described a group organized at UCSB
   to investigate the network resources.  The stated goals were to
   develop problem solving capability and, in the process, produce
   helpful criticism for the nodes investigated.  This report summarizes
   the group's experiences and finding and suggests network refinements
   to improve user satisfaction.

   The group's encounter with ARPANET included many unexpected problems
   and difficulties.  Most worthy of mention are software heterogeneity
   and inadequate documentation.

   From this first hand experience the group has formulated criteria for
   ease in use of network resources.  The report presents these criteria
   as well as suggestions for improved documentation, better utilization
   of current resources, and a plea for regular usage of inter-personal
   communications facilities.  Individual sites have been graded on
   reliability, response, and friendliness.  Comments regarding specific
   sites have been included to help in adapting to the needs of
   uninitiated users.

   Despite problems encountered in the initial nine week exposure,
   enough was learned of ARPANET resources to enable the group to write
   useful software.  Programs to effect automatic login, file transfer,
   and interprocess communication have been written and put to use.

TABLE OF CONTENTS

      BACKGROUND
         Approach.......................................  2
         Goals..........................................  2
      THE SURVEY
         Extent and Duration............................  3
         Statistical Results............................  3
      CRITIQUE OF ARPANET SERVICES
         A Site Measurement Parameter, "Friendliness"...  4
         Software Critique..............................  5
         Community Spirit...............................  5
         Economics......................................  6

      SUGGESTIONS FOR IMPROVEMENT
         Software.......................................  6
         Community Spirit...............................  7
      CONCLUSION........................................  8
      APPENDIX A
         Sample of Survey Questionnaire................   9
      APPENDIX B
         Grades and Comments for Specifics Sites.......  10

BACKGROUND

Approach

   The test group was organized from a group of Electrical Engineering
   graduate students in Computer Science.  Within the group was
   represented a substantial degree of experience with high level
   languages and time sharing systems (such as the Dartmouth BASIC and
   UCSB mathematical graphics systems).  However, no one had experience
   in exercising ARPANET, and few knew what resources the ARPANET
   represented.  After two weeks of presentation from Jim White and
   Roland Bryan, the group was turned loose for open experimentation.

   Enthusiasm was high as each group managed to locate and decode the
   login procedures for various nodes and began to learn how to use the
   available resources.  In fact, half of the weekly seminar time was
   devoted to sharing learned experiences and procedures.  Interest,
   however, lagged some as the quarter progressed due to poor network
   site reliability, few active nodes, and hard to locate documentation
   (only five out of fourteen students remained active after the first
   quarter).

Goals

   The primary goal of the group was to learn how to use and to evaluate
   network resources.  It was decided to be fair but direct in
   evaluating each site, including UCSB.  Since the level of networking
   experience was initially low, the evaluation criteria was dictated
   mostly by gut feelings.

   At the conclusion of the first quarter's effort, a questionnaire was
   given to the students (a sample of which is included in Appendix A).

   The group response is summarized for overall performance below.  Data
   for individual sites is presented in Appendix B. Some of the
   questions asked were the following:

      Estimate percentage of time spent in various trouble states
      Estimate the mean time to failure
      Describe personal experience with the network
      Suggest improvements
      Grade the investigated nodes on the factors of reliability,
      response, and friendliness

THE SURVEY

Extent and Duration

   During the period in which the major effort was expended (January-
   March, 1972) relatively few nodes were active.  Experimentation,
   therefore, concentrated most heavily on UCSB, BBN-TENEX, MIT-MULTICS,
   and SRI-ARC.  Minor investigation was performed of HARV-10, UCLA-NMC,
   and UCLA-CCN.  The remaining sites were either inactive or
   inaccessible for lack of documentation.

   Activity included the following:

      Game playing (e.g., chess, life, and doctor at BBN-TENEX)
      Text and file manipulation (e.g., COL, NLS, TECO)
      Inter-personal communication (LINK and SNDMSG)
      On line compilation (e.g., TENEX FORTRAN, MULTICS PL/1).

Statistical Results

   Figure 1 below summarizes the overall response to the questionnaire
   given to the group after nine weeks experience with the ARPANET.
   Individual exposure varied from ten to sixty hours, and twelve
   students responded.  Each survey item is presented as a group average
   (sum/12) and is supplemented with a low and a high value to show the
   range of response.  The questions were slightly ambiguous in that
   they failed to distinguish between node inactivity and local NCP
   inactivity.  Also, some figures may reflect individual students'
   inadequacy in understanding local and foreign procedures.
   Nevertheless, the data is interesting as a look into uninitiated user
   experience.

Figure 1

   Survey Item                                Average    Low    High

   % of time unable to log in any site         12,4%     2%     25%
   % of time unable to log into desired site   35.7      20     75
   % of time foreign site suddenly crashes     13        5      50
   % of time local site suddenly crashes       12.5      5      25
   % of time trouble free operation            35        0      80
   Approximate mean-time-between-failure       1h       5 min   2 hrs

   TOTAL TIME INVESTED                         32.3hrs  10 hrs  60 hrs

   First to be noted is that considering the entire ARPANET complex, no
   one approximated the mean-time-between-failure at more than two
   hours!  Secondly, the average time for "trouble free" operation was
   35%, a figure untenable for regular user usage.  In all fairness,
   however, some sites were much more "trouble free" than others, and
   individuals tend to define the term by the level of their own
   competence and experience, thus explaining the high of 80% and the
   low of 0%.

CRITIQUE OF ARPANET SERVICES

A Site Measurement Parameter, Friendliness

   Much discussed by the group was the concept of "friendliness",
   especially as it applies to on-line systems.  The following
   definition of friendliness is offered, based on direct network
   experience.

   Friendliness is:

      Concise, complete, and available documentation.
      Easy system usage (e.g., minimum numbers of keys for login
      system and job status readily available).
      Easy to reach help both on-line people and on-line files.
      No messages overkill (as sometimes unexpectedly occurs
      during login).
      Reasonable reliability and response time
      Concise, but informative error diagnostics

   The reader can probably think of more criteria, but these were the
   outstanding points of friendliness generated specifically by the
   group's experience.

Software Critique

   1) Initial experimentation concentrated on login procedures, canned
   scenarios (e.g., Abhay K. Bhushan's ARPANET scenario, RFC #254), game
   playing, and inter-personal communication.  As the effort continued,
   attempts were made to solve problems at various nodes.  One student,
   for example, programmed a Newton-Raphson root finder in PL/1 at MIT-
   MULTICS a blackbody problem in FORTRAN at BBN-TENEX and MIT-MULTICS,
   and in PL/1 at MIT-MULTICS; and a Discrete Fourier Transform in BASIC
   at BBN-TENEX.  It is the group's conclusion that small problems can
   be written in a half hour, entered and edited in fifteen minutes and
   debugged in another fifteen minutes.  For small problems the current
   ARPANET software resources are quite adequate.

   2) By far the most annoying difficulty was obtaining adequate
   documentation.  The resource notebook was found to be interesting but
   of limited utility.

   3) Information about each node's NCP, which was requested in
   February, 1972, is still unavailable.

   4) Significant variations in procedures were found in executing
   similar tasks on different nodes.  Consider, for example, the wide
   variety of text editors with unique file naming, editing, and
   manipulation commands (TENEX, TECO, COL, NLS...).  Consider, too, the
   wide variety of compilation, load and execute procedures (RJE for
   UCSB edit, save, compile, save, load, execute for TENEX systems).
   Even more disparate are the "executive level" commands with all their
   varieties (TENEX's "Control-C", UCLA-NMC's "X", UCSB's "RESET" ...
   all of which return to the "top-lvel").  Software heterogeneity is a
   stumbling block to the user.

   5) Residents of large nodes are hard pressed to find problems which
   should be solved outside of the local environment.  With UCSB's
   mathematical graphics on-line system and direct access to batch, the
   group experienced apprehensive twinges spending hours on the network
   solving problems which could be solved in minutes locally.

Community Spirit

   1) Individuals sometimes got the impression (erroneously it is hoped)
   that some researchers in the ARPA community had little desire to
   consult and/or help.  On the other hand, others bent over backwards
   in giving assistance.  The group had hoped for a more consistent
   response.

   2) There was difficulty in locating the source of responsibility for
   resource development.  It seemed to the seminar group that the
   complete distribution of responsibility negated incentive to locate,
   document, and create useful network resources.

Economics

   Network economics at levels above as well as the communications
   level, are a big user problem, e.g., if distributed computing is
   allowed, then distributed billing is a necessity.  It is frustrating
   to watch accounts randomly die at different nodes and have to spend
   weeks in monetary renovation.  This problem was experienced with a
   site which (a) randomly changed passwords and then (b) eliminated its
   free account.  Also there is a problem with double connect charges,
   e.g., $4.00 per hour at UCSB to sign on to BBN-TENEX at $8.00 per
   hour, which totals to $12.00 per hour!

SUGGESTIONS FOR IMPROVEMENT

   In spite of the many difficulties and frustrations, the class was
   impressed with the potential of ARPANET and produced several
   suggestions for improvement.

Software

   1) Working groups should be organized to define problems which
   require the use of a significant set of the network resources.

   2) The ARPANET represents a great resource already, even with TELNET
   as the only operational protocol.  More effort should be put in
   utilization of what currently exists.  Two illustrative examples
   follow:

      a) By combining the resources represented by UCSB's OLS and UCSB's
         TELNET, user programs were created to sign on automatically to
         the various sites.  Thus a network user need know only the
         sign-on procedure for UCSB; all settings of local/remote echo,
         character/line at a time, upper/lower case, etc. are taken care
         of automatically by the pre-written user programs.

      b) Combining the resources of TELNET PROTOCOL, PL/1 subroutine
         calls to the UCSB NCP, and 360 O/S multi-programming, a group
         of students created a batch-fed command language in PL/1 to
         communicate via telnet with foreign sites.  This program has
         been used successfully to investigate file transfer (NIC files
         are regularly copied on 8-1/2 x 11" white printer paper, and
         cards will soon be transferred to I4-TENEX), interprocess
         communication (a program was started at BBN-TENEX to be used as

         a subroutine locally; plans exist to initiate and monitor a
         chess game between BBN-TENEX and SU-AI), and data transfer
         (pre-formatted files of data have been transferred from UCLA-
         NMC to UCSB; UCLA-NMC will soon make available survey and
         measurement data ala TELNET PROTOCOL and through direct ICP!).
         Moe details of this program will be available in a future
         report.

   3) Documentation: A self-sufficient mini-user-manual (MINIMAN) should
   exist for each site and also for each function network wide, such as
   the FORTRAN compilers.  The MINIMAN would be similar in some respects
   to the resource notebook, but would be more oriented to helping the
   user run.  A site dependent MINIMAN would contain the following:

      Sign on procedure
      Simple file manipulation and editing commands
      Compilation and execution instructions
      TELNET access
      Brief (!) summary of programs and subroutines
      Direction on how to get help.

   Overall documentation of hardware, software and human resources
   should be more complete.  A documentation questionnaire should
   perhaps be circulated to authors of network programs, including the
   authors of Network Control Programs.  Merging information from the
   questionnaire with the Resource Notebook would facilitate the
   construction of a resource-location cross referenced index.  Such an
   index, perhaps on-line, would aid the network user in locating both
   software and hardware.  Whatever the final scheme, more planning is
   required to improve the user versus documentation battle.  The recent
   effort in this direction by Marshall D. Abrams entitled "Serving
   Remote Users on the ARPANET" (NIC 10606 RFC #364) is well timed and
   should be thoroughly considered.

   4) Finally, high level subroutine calls to each NCP, such as those
   offered by UCSB, should be universally available.

Community Spirit

   1) Networks have great though unexploited potential for inter-
   personal communication.  The communication resources (NIC's JOURNAL,
   NLS TENEX's SENDMSG, LINK; UCLA-NMC'S S_.MSG:C to name a few) are
   used today only by the proficient few, but should be utilized
   regularly by all.  Two symptoms of the current state of network
   communications from the group's point of view are that most
   procedural information was shared verbally in class and that many

   problems in locating documentation were solved by a last resort to
   that old standby, the telephone.  Improved communications will
   stimulate cooperation on joint projects.

   2) Names and interests of programmers/researchers willing to
   cooperate on joint projects and corresponding "blue sky" lists of
   software projects should be maintained.

   3) A network NEWS and NOTES should be published to inform and advise
   network participants of new resources and procedural modifications.
   Care must be taken, however, to keep this document concise (i.e.,
   avoid "message over-kill").  Perhaps a one page flier published
   weekly would meet this need.

   4) A network consulting center should be created, perhaps at the
   existing NIC, which would specialize in non-partisan matching of
   network users to network resources.

   5) A strong potential of the network is in Computer Science
   education.  Being exposed to many varieties of computer systems helps
   the student/user avoid the narrowness of experience and opinion which
   sometimes exists in centers of learning and computing.  In this
   respect the TIP user is probably the most benefited as, for little
   investment in local resources, many styles of systems are at his
   "finger-tips".  Yet even for service nodes, the network represents an
   inexpensive extension to local educational resources.  Current
   efforts to tap the educational value of ARPANET should be encouraged
   and extended.

CONCLUSION

   Existing site surveys measure and evaluate the performance of IMP
   hardware, host hardware, and host NCP programs, but little has been
   done to evaluate software performance.  The UCSB EE 210 graduate
   students attempted a primitive first pass evaluation of network
   resources in the period between January and March 1972.  Out of this
   effort have come definitions and criteria which would be useful to
   other individuals or agencies in developing evaluation schemes on the
   USER protocol level.  To this end, it is hoped that this report is
   useful.

APPENDIX A - Sample Student Questionnaire

ARPANET

   Grade Given:  A=Excellent                 Evaluation by:
                 F=Bad

   -------------------------------------------------------------------
   SITE | RELIABILITY| RESPONSE | FRIENDLINESS | # HOURS  | COMMENTS |
        |            |          |              |   USED   |          |
   -----|------------|----------|--------------|----------|----------|
        |            |          |              |          |          |
        |            |          |              |          |          |

                            ARPANET Evaluation

   -- Indicate % of your sessions which were in the following categories:

              %               State
         +--------+-------------------------------------------+
         |        |  Unable to Log in to any site.            |
         |--------|-------------------------------------------|
         |        |  Unable to Log in to Desired site.        |
         |--------|-------------------------------------------|
         |        |  Foreign site suddenly crashes.           |
         |--------|-------------------------------------------|
         |        |  Local site crashes.                      |
         |--------|-------------------------------------------|
         |        |  Trouble free operation.                  |
         |--------|-------------------------------------------|
         |        |  Other                                    |
         +--------+-------------------------------------------+

   -- Considering the performance of the local host, communication
      network, and remote hosts, estimate the mean time to failure of
      ARPANET:
         Mean-Time-Between-Failure=___________

   -- What was your total time invested in the ARPANET this quarter?
         Total Time Invested=___________

   -- Describe your overall experience with the ARPANET (e.g., rise and
      fall of personal interest factors involved, etc.).

   -- What suggestions for changes or improvements or new capabilities
      do you have to make to ARPANET hosts?

      (Use back side or other paper for these questions if necessary)

APPENDIX B - Specific Sites, Grades and Comments

   The following grades and comments are based on the two to four most
   representative questionnaire responses for each site.  Reliability,
   Response, and Friendliness are averaged grades and reflect subjective
   criticism.  Total Invested time is the sum total of the
   experimentation times reported by individual respondents.  It is
   hoped that future evaluations might be more specific and complete
   than the current efforts, yet the value of these initial efforts
   should not be underestimated.

   Grades:

         A=Excellent

         F=Bad
                                                    Total Time
   Site        Reliability  Response  Friendliness   Invested
   --------------------------------------------------------------
   BBN-TENEX       A            A         A             71 hours
   UCSB            B            B+        B-            36
   SRI-ARC         B            B         A             75
   HARV-10         C            A-        B             14
   UCLA-NMC        C-           C         D             14
   MIT-MULTICS     C-           D         C+            82
   --------------------------------------------------------------

Group Comments

      Site:  BBN-TENEX
         Very popular site
         Doctor, life and chess are stimulating and easy to use games
         Operators are very helpful
         Account problems kept site from being useful
         BASIC is well-written and easy to use
         FORTRAN is difficult to use because of the many steps to
         create-compile-execute.

      Site:  UCSB
         There are many problems with old key boards
         TELNET diagnostics are poor
         Online help files are sorely lacking
         Graphics are necessary for full utility
         Operator would not reload NCP when down
         List of TELNET site names are not current or complete

      Site:  SRI-ARC
         Good documentation exists on NLS specifics, but general
           overview is lacking
         Inter-console link is convenient and often used.
         NLS-JOURNAL is useful but requires significant training
         Online perusal is difficult at terminals with small display faces.

      Site:  HARV-10
         Operator is readily available
         FORTRAN is straight forward
         Easy to use editor
         Couldn't get operator to put BASIC on.

      Site:  UCLA-NMC
         Self-explanatory ABACUS program is not self-explanatory
         System often disappears
         Hard to get past LOG ON* without TIMEOUT GOODBYE
         Message system is well organized.

      Site:  UCLA-CCN
         Always up, but nothing can be done (HELP is not supported)
         When RJS is executed, there is no response until correct signon
         procedure is entered (spurious death indication).

      Site:  MIT-MULTICS
         Response is very slow
         Automatic logout of autonomous user is excruciatingly painful
         Text editor is very easy and helpful
         PL/1 and FORTRAN are easy to use.

        [This RFC was put into machine readable form for entry]
     [into the online RFC archives by Hélène Morin, Viagénie 12/99]

 

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