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 RFCwas put into machine readable form for entry]
