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        APRANET History of Network Working Group and NCP.

Comments and Criticisms Welcome. This paper will be in 3 or 4
parts depending on if I decide to post parts of the appendices in
a 4th part.

    Behind the Net: The untold history of the ARPANET

                        By Michael Hauben
                       [e-mail]

     The global Internet's progenitor was the Advanced Research
Projects Agency Network (ARPANET) of the U.S. Department of
Defense. This is important to remember, because the support and
style of management by ARPA to its contractors was crucial to the
success of the ARPANET. As the Internet develops and the struggle
over the role it plays unfolds, it will be important to remember
how the network developed and the culture with which it was
connected. As a facilitator of communication, the culture of the
Net is an important feature to acknowledge.

     The ARPANET Completion Report, as published jointly by Bolt,
Beranek and Newman (BBN) of Cambridge, Mass., and ARPA concludes
by stating:

     ...it is somewhat fitting to end on the note that the
     ARPANET program has had a strong and direct feedback into
     the support and strength of computer science, from which the
     network itself sprung. (Chapter III, pg.132, Section 2.3.4)

In order to understand the wonder that the Internet, and various
parts of the Net, represent, we need to understand why the
ARPANET Completion report ends with the suggestion that the
ARPANET is fundamentally connected to and born of computer
science, rather than of the military.

      PART I: The history of ARPA leading up to the ARPANET

     A climate of pure research surrounded the entire history of
the ARPANET. The Advanced Research Projects Agency was formed to
fund research, and thus was not oriented to a military product.
The formation of this agency was part of the U.S. reaction to the
then Soviet Union's launch of Sputnik in 1957. (ARPA draft,
III-6). ARPA was assigned to research how to utilize the mili-
tary's investment in computers via Command and Control Research
(CCR). Dr. J.C.R. Licklider was chosen to head this effort.
Licklider came to ARPA from Bolt, Beranek and Newman, (BBN) in
Cambridge, MA in October 1962. (ARPA draft, III-6) He came to
ARPA from a background of combining engineering studies and
physiological psychology. This provided Licklider with an unusual
prospective uncommon among engineers.

     From Licklider's arrival, the department's contracts were
shifted from independent corporations towards "the best academic
computer centers" (ARPA draft, III-7). The then current method of
computing was via batch processing (i.e., input via stacks of
punched cards, and output: the results, or lack of them, made
known one or more days later.). Licklider saw improvements could
be made in CCR only from work on advancing the current state of
computing technology. He particularly wanted to move forward into
the age of interactive computing, and the current contractors
were not moving in that direction. In an Interview, Licklider
told the interviewee that SDC (Systems Development Corporation)
"was based on batch processing, and while I was interested in a
new way of doing things, they [SDC] were studying how to make
improvements in the ways things were done already." (An Interview
with J.C.R. Licklider conducted by William Aspray and Arthur
Norberg on October 28, 1988 Cambridge, Mass. CBI Univ of Minn.,
Madison) The office "developed into a far-reaching basic research
program in advanced technology." (ARPA draft III-7) Licklider's
Office was renamed Information Processing Techniques Office (IPT
or IPTO) to reflect that change.

     The Completion report states that "Prophetically, Licklider
nicknamed the group of computer specialists he gathered the
'Intergalactic Network'." (ARPA draft, III-7) Before work on the
ARPANET began, the very idea of the network was planted by the
creation of the Information Processing Techniques Office of ARPA.
Robert Taylor, Licklider's successor at the IPTO, remembers why
this was true because of Lick's interest in interconnecting
communities:

     Lick was among the first to perceive the spirit of community
     created among the users of the first time-sharing systems...
     In pointing out the community phenomena created, in part, by
     the sharing of resources in one timesharing system, Lick
     made it easy to think about interconnecting the communities,
     the interconnection of interactive, on-line communities of
     people, ..." (ARPA draft, III-21)

     The "spirit of community" was related to Lick's interest in
having computers help people communicate with other people
(Licklider and Robert Taylor, "The Computer as a Communication
Device") Licklider's vision of an "intergalactic network" con-
necting people represented an important conceptional shift in
computer science. This vision was also an important beginning to
the ARPANET. After the ARPANET was up and running, the computer
scientists using it realized that assisting human communication
was a major fundamental advance that the ARPANET made possible.

     As early as 1963, a commonly asked question of the IPTO
directors by the ARPA directors about IPTO projects was "Why
don't we rely on the computer industry to do that?", or occasion-
ally more strongly, "We should not support that effort because
ABC (read, "computer industry") will do it - if it's worth
doing!" (ARPA draft, III-23) This question leads to an important
point - this ARPA research was different from what the computer
industry had in mind to do - or was likely to undertake. Since
Licklider's creation of the IPTO, the work supported by ARPA/IPTO
continued his explicit emphasis on communications. The Completion
Report explains,

     The ARPA theme is that the promise offered by the computer
     as a communication medium between people, dwarfs into rela-
     tive insignificance the historical beginnings of the comput-
     er as an arithmetic engine." (ARPA draft, III-24)

The Completion Report goes on to differentiate ARPA from the
computer industry:

     The computer industry, in the main, still thinks of the
     computer as an arithmetic engine. Their heritage is reflect-
     ed even in current designs of their communication systems.
     They have an economic and psychological commitment to the
     arithmetic engine model, and it can die only slowly..."
     (ARPA draft, III-24)

The Completion Report further analyzes this problem by tracing it
back to the nation's universities:

     ...furthermore, it is a view that is still reinforced by
     most of the nation's computer science programs. Even univer-
     sities, or at least parts of them, are held in the grasp of
     the arithmetic engine concept.... (ARPA draft, III-24)

     ARPA's IPTO was responsible for the research and development
which led to the success of first the ARPANET, and later the
Internet. Without the commitment that existed via this support,
such a development might never have happened. One of ARPA's
criterion for supporting research was that the research had to be
of such a level as to offer an order of magnitude of advance over
the current state of development. As most research and develop-
ment is not immediately profitable, there is a need for organiza-
tions which do not pursue profit as their goal, but rather work
on furthering the state of the art. What is very telling is that
computer networking spread widely without profit being involved.

     Others have understood the communications promise of comput-
ers. For example, in RFC 1336, David Clark, senior research
scientist at MIT's laboratory for computer science, is quoted,

     It is not proper to think of networks as connecting comput-
     ers. Rather, they connect people using computers to mediate.
     The great success of the internet is not technical, but in
     human impact. Electronic mail may not be a wonderful advance
     in Computer Science, but it is a whole new way for people to
     communicate. The continued growth of the Internet is a
     technical challenge to all of us, but we must never loose
     sight of where we came from, the great change we have worked
     on the larger computer community, and the great potential we
     have for future change.

     Various research predating the ARPANET had been done by Paul
Baron, Thomas Marill and others. [End note 1] This led Lawrence
Roberts and other IPTO staff to formally introduce the topic of
networking computers of differing types (i.e.: incompatible
hardware and software) together in order to share resources to
the early 1967 meeting of ARPA's Principle Investigators (PI).

     In the spring of 1967 at the University of Michigan, ARPA
held its yearly meeting of the Principle Investigators from each
of its university and other contractors. (ARPA draft, III-25)
Results from the previous year's research was summarized and
future research was discussed, either introduced by ARPA or the
various researchers present at the meeting. Networking was one of
the topics brought up at this meeting. (ARPA draft, III-25) At
that meeting, it was decided that there had to be agreement on
conventions for character and block transmission, error checking
and retransmission, and computer and user identification. These
specifications became the contents of the inter-host
communication's "protocol." Frank Westervelt was chosen to write
about this protocol and a communication group was formed to study
the questions. (ARPA draft, III-26)

     In order to develop a network of varied computers, two main
problems had to be solved:

     1. To construct a 'subnetwork' consisting of telephone
     circuits and switching nodes whose reliability, delay char-
     acteristics, capacity, and cost would facilitate resource
     sharing among computers on the network.

     2. To understand, design, and implement the protocols and
     procedures within the operating systems of each connected
     computer, in order to allow the use of the new subnetwork by
     the computers in sharing resources. (ARPA, II-8)

     After one draft and additional work on this communications
position paper was completed, a meeting was scheduled in early
October 1967 by ARPA at which the protocol paper and specifica-
tions for the Interface Message Processor (IMP) were discussed. A
subnetwork of IMPs, dedicated mini-computers connected to each of
the participant computers, was the method chosen to connect the
participants's computers (hosts) to each other via phone lines.
This standardized the subnet to which the hosts connected. Now,
only the connection of the hosts to the network would depend on
vendor type, etc. ARPA had picked 19 possible participants in
what was now known as the "ARPA Network."

     From the time of the 1967 PI Meeting, various computer
scientists who were ARPA contractors were busy thinking about
various aspects which would be relevant to the planning and
development of the ARPANET. Part of that work was a document
outlining a beginning design for the IMP subnetwork. This speci-
fication led to a competitive procurement for the design of the
IMP subnetwork.

     By late 1967 ARPA had given a contract to the Stanford
Research Institute (SRI) to write the specifications for the
communications network they were developing. In December of 1968,
SRI issued a report "A Study of Computer Network Design Parame-
ters." Elmer Shapiro played an important role in the research for
this report. Based on this work, Roberts and Barry Wessler of
ARPA wrote the final ARPA version of the IMP specification. (ARPA
draft, III-32) This specification was ready to be discussed at
the June 1968 PI meeting.

     The Program Plan "Resource Sharing Computer Networks" was
submitted June 3, 1968 by the IPTO to the ARPA Director, who
approved it on June 21, 1968. It outlined the objectives of the
research, and the plan of how the objectives would be fulfilled.
The purposed network was impressive as it would prove useful to
both the computing research centers which connected to the
network and the military. The proposed requirements for the
research would provide immediate benefits to the computer centers
the network would connect. (ARPA draft, III-35) ARPA's stated
objectives were to experiment with varied interconnections of
computers and sharing resources in an attempt to improve produc-
tivity of computer research. (ARPA, II-2) Justification was drawn
from technical needs in both the scientific and military environ-
ments. The Program Plan developed into a set of specifications.
These specifications were connected to a competitive Request for
Quotation (RFQ) to find an organization which would design and
build the IMP subnetwork.

     Following the approval of the Program Plan, 140 potential
bidders were mailed the Request for Quotation. After a bidders
conference, 12 proposals were received and from them ARPA nar-
rowed the bidders down to four. BBN was the eventual recipient of
the contract. (ARPA draft, III-35)

     The second technical problem, as defined by the ad hoc
Communications Group, still remained to be solved. The set of
agreed upon communications settings (known as a protocol), which
would allow the hosts to communicate with each other over the
subnetwork, had to be developed. This work was left "for host
sites to work out among themselves." (ARPA draft, III-67) This
meant that the software necessary to connect the hosts to the IMP
subnetwork had to be developed. ARPA assigned this duty to the
initially designated ARPANET sites. Each of the first sites had a
different type of computer to connect. ARPA trusted/knew the
programmers at each site would be capable of modifying their
operating systems in order to connect their systems to the
subnetwork. In addition the sites needed to develop the software
necessary to utilize the other hosts on the network. (ARPA draft,
III-39) ARPA's assigning of responsibilities made the academic
computer science community an active part of the ARPANET develop-
ment team. (Interview with Alex McKenize, Nov, 1 1993)

     Steve Crocker, one of graduate students involved with the
development of the earliest ARPANET protocols, associates the
placement of the initial ARPANET sites at research institutions
to the fact that the ARPANET was ground-breaking research. He
wrote in a message responding to my questions on the COM-PRIV
mailing list:

     During the initial development of the Arpanet, there was
     simply a limit as to how far ahead anyone could see and
     manage. The IMPs were placed in cooperative ARPA R&D sites
     with the hope that these research sites would figure out how
     to exploit this new communication medium. (Crocker, 1993A)

     The first sites of the ARPANET were picked to provide either
network support services or unique resources. The key services
the first four sites provided were

     UCLA - Network Measurement Center
     SRI  - Network Information Center
     UCSB - Culler-Fried interactive mathematics
     UTAH - graphics (hidden line removal)
    (Cerf, Vinton 1993)

Steve Crocker also recounts that the reason for selecting these
particular four sites was because they were "existing ARPA
computer science research contractors." This was important
because "the research community could be counted on to take some
initiative." (RFC 1000, pg 1)

     The very first site to receive an IMP was UCLA. Professor
Leonard Kleinrock of UCLA was involved with much of the early
development of the ARPANET. His work in queuing theory gave him a
basis to develop measurement techniques used to monitor the
ARPANET's performance. This made it natural to make sure that
UCLA received one of the first nodes as it would be important to
measure the network's activity from early on. In order for the
statistics to have correct data and analysis purposes - one of
the first two or three sites had to be the measurement site. Sure
enough UCLA was assigned to be the Network Measurement Center
(NMC). [END NOTE 2]


               Part II. The Network Working Group

     Once the initial sites were picked, representatives from
each site gathered together to start talking about solving the
technical problem of getting the hosts to communicate with each
other. The ARPA Completion report tells us about this beginning:

     To provide the hosts with a little impetus to work on the
     host-to-host problems. ARPA assigned Elmer Shapiro of SRI
     "to make something happen", a typically vague ARPA assign-
     ment. Shapiro called a meeting in the summer of 1968 which
     was attended by programmers from several of the first hosts
     to be connected to the network. Individuals who were present
     have said that it was clear from the meeting at that time,
     no one had even any clear notions of what the fundamental
     host-to-host issues might be. (AC Draft III-67 1.4.1.7)

     We see that this group, which came to be known as the
Network Working Group (NWG), was exploring new territory. The
first meeting took place several months before the first IMP was
put together and they had to think from a blank slate. Throughout
the existing recollections of the important developments the NWG
produced, (especially RFC 1000) the reader is reminded that the
thinking involved was groundbreaking and thus exciting. Steve
Crocker remembers in the RFC Reference Guide (RFC 1000) that the
first meeting was chaired by Elmer Shapiro, who initiated the
conversation with a list of questions. (Crocker, 1993b) Also
present were Steve Carr from University of Utah, Stephen Crocker
from UCLA, Jeff Rulifson from SRI, and Ron Stoughton from UCSB.
These attendees are the programmers referred to in the ARPANET
Completion Report.

     According to Steve Crocker, this was a seminal meeting. The
attendees could only be but theoretical, as none of the lowest
levels of communication had been developed yet. They needed a
transport layer or low-level communications platform to be able
to build upon. BBN would not deliver the first IMP until August
30, 1969. It was important to meet before this date, as the NWG
"imagined all sorts of possibilities." (Rfc1000) Only once their
thought processes started could this working group actually
develop anything. These fresh thoughts from fresh minds helped to
incubate new ideas. The ARPANET Completion Report properly
acknowledges what this early group helped accomplished: "Their
early thinking was at a very high level." (ARPA draft, III-67) A
concrete decision of the first meeting was to continue holding
meetings similar to the first one. This wound up setting the
precedent of holding exchange meetings at each of the sites.

     Steve Crocker, describing the problems facing these network-
ing pioneers, writes:

     With no specific service definition in place for what the
     IMPs were providing to the hosts, there wasn't any clear
     idea of what work the hosts had to do. Only later did we
     articulate the notion of building a layered set of protocols
     with general transport services on the bottom and multiple
     application-specific protocols on the top. More precisely,
     we understood quite early that we wanted quite a bit of
     generality, but we didn't have a clear idea how to achieve
     it. We struggled between a grand design and getting some-
     thing working quickly. (Crocker,1993c)

     The initial protocol development lead to DEL (Decode-
Encode-Language) and NIL (Network Interchange Language). These
languages were more advanced than what was needed or possible at
the time. The basic purpose was to form an on-the-fly description
that would tell the receiving end how to understand the informa-
tion that would be sent. These first set of meetings were ex-
tremely abstract as neither ARPA nor the universities had deemed
any official charter. However, the lack of a charter allowed the
group to think broadly and openly.

     BBN did submit details about the host-IMP interface specifi-
cations from the IMP side. This information provided the group
some definite starting points to build from. Soon after BBN
provided more information, on Valentine's Day, 1969, members of
the NWG, members of BBN and members of the Network Analysis
Corporation (NAC) met for the first time. [Endnote 3]
As all the parties had different priorities on mind, the meeting
was a difficult one. BBN was interested in the lowest level of
making a reliable connection. The programmers from the host sites
were interested in getting the hosts to communicate with each
either via various higher level programs. And BBN also did not
turn out to be the "experts from the East" that Steve Crocker
wrote the members of the NWG expected. He continues by writing in
RFC 1000 that they constantly thought that "a professional crew
would show up eventually to take over the problems we were
dealing with."

     A step of incredible importance and openness occurred as a
result from a "particularly delightful" meeting that took place a
month later in Utah. (RFC1000) The participants decided it was
time to start recording their meetings in a consistent fashion.
What resulted was a set of informal notes titled "Request for
Comments." Steve Crocker writes about their formation:

     I remember having great fear that we would offend whomever
     the official protocol designers were, and I spent a sleep-
     less night composing humble words for our notes. The basic
     ground rules were that anyone could say anything and that
     nothing was official. And to emphasize the point, I labeled
     the notes "Request for Comments." I never dreamed these
     notes would distributed through the very medium we were
     discussing in these notes. Talk about Sorcerer's Apprentice!
     (Crocker, RFC 1000, pg 3, 1987)

     Crocker replaced Shapiro as the Chairman of the NWG soon
after the initial meeting. He describes how they wrestled with
the creation of the host-host protocols:

     Over the spring and summer of 1969 we grappled with the
     detailed problems of protocol design. Although we had a
     vision of the vast potential for intercomputer communica-
     tion, designing usable protocols was another matter. A
     custom hardware interface and custom intrusion into the
     operating system was going to be required for anything we
     designed, and we anticipated serious difficulty at each of
     the sites. We looked for existing abstractions to use. It
     would have been convenient if we could have made the network
     simply look like a tape drive to each host, but we knew that
     wouldn't do. (Crocker, RFC 1000, pg. 3)

     The first IMP was delivered to UCLA in late August, 1969.
The next was delivered to SRI a month later in October. [Endnote
4] Once more than one IMP existed, the NWG had to implement a
working communications protocol. This first set of pairwise host
protocols included remote login for interactive use (telnet), and
a way to copy files between remote hosts (FTP). Crocker writes:

     In particular, only asymmetric, user-server relationships
     were supported. In December 1969, we met with Larry Roberts
     in Utah, [and he] made it abundantly clear that our first
     step was not big enough, and we went back to the drawing
     board. Over the next few months we designed a symmetric
     host-host protocol, and we defined an abstract implementa-
     tion of the protocol known as the Network Control Program.
     ("NCP" later came to be used as the name for the protocol,
     but it originally meant the program within the operating
     system that managed connections. The protocol itself was
     known blandly only as the host-host protocol.) Along with
     the basic host-host protocol, we also envisioned a hierarchy
     of protocols, with Telnet, FTP and some splinter protocols
     as the first examples. If we had only consulted the ancient
     mystics, we would have seen immediately that seven layers
     were required. (RFC 1000, pg 4)

     After Robert's guidance, the Network Working Group went
forward in developing the protocols necessary to make the network
viable. The group swelled in attendance as more and more sites
connected to the ARPANET. The group became large enough (around
100 people) that one meeting was held in conjunction with the
1971 Spring Joint Computer Conference in Atlantic City. A major
test of the NWG's work came in October 1971, when a meeting was
held at MIT. Crocker continues the story,

     [A] major protocol "fly-off" - Representatives from each
     site were on hand, and everyone tried to log in to everyone
     else's site. With the exception of one site that was com-
     pletely down, the matrix was almost completely filled in,
     and we had reached a major milestone in connectivity.
     (Crocker, RFC 1000, pg. 4)

     The NCP was created as what was called the "host to host
protocol." Explaining why this was important, the authors of the
ARPA draft write:

     The problem is to design a host protocol which is suffi-
     ciently powerful for the kinds of communication that will
     occur and yet can be implemented in all of the various
     different host computer systems. The initial approach taken
     involved an entity called a "Network Control Program" which
     would typically reside in the executive of a host, such that
     processes within a host would communicate with the network
     through this Network Control Program. The primary function
     of the NCP is to establish connections, break connections,
     switch connections, and control flow. A layered approach was
     taken such that more complex procedures (such as File Trans-
     fer Procedures) were built on top of similar procedures in
     the host Network Control Program. (Arpa draft, II-24)

     As the ARPANET grew, the number of users bypassed the number
of developers. This signaled the success of these networking
pioneers. Steve Crocker appointed Alex McKenize and Jon Postel to
replace him as Chairmen of the Network Working Group. The Comple-
tion Report details how this role changed:

     McKenzie and Postel interpreted their task to be one of
     codification and coordination primarily, and after a few
     more spurts of activity the protocol definition process
     settled for the most part into a status of a maintenance
     effort.(ARPA draft,III-69)

     ARPA was a management body which funded academic computer
scientists. ARPA's funding paved the way for these scientists to
create the ARPANET. BBN helped via developing the packet switch-
ing techniques which served as the bottom level of transmitting
information between sites. The NWG provided an important develop-
ment in its "Request for Comments" documentation which made
possible the developing the new protocols.


          PART III. About RFC's as "Open" Documentation

     The openness initiated from the very first meeting of the
Network Working Group continued on in a more informal formalized
manner in the Request For Comments. As meeting notes, the RFCs
were meant to keep members updated on the status of various
developments and ideas by the development community. They were
also meant to gather responses from people. The Documentation
Conventions RFC (RFC 3) documents the "rules" governing the
production of these notes. Heading the page were the open distri-
bution rules:

     Documentation of the NWG's effort is through notes such as
     this. Notes may be produced at any site by anybody and
     included in this series.

These opening sentences invite anyone willing to be helpful in
the protocol definition process. This is important because all
restrictions are denied by these words, allowing for the best
possible developments. The guide goes on to describe the rules
concerning the contents of the RFCs:

     The content of a NWG note may be any thought, suggestion,
     etc. related to the HOST software or other aspect of the
     network. Notes are encouraged to be timely rather than
     polished. Philosophical positions without examples or other
     specifics, specific suggestions or implementation techniques
     without introductory or background explication, and explicit
     questions without any attempted answers are all acceptable.
     The minimum length for a NWG note is one sentence.

The RFC continues to explain the philosophy behind the perhaps
unprecedented amount of openness represented:

     These standards (or lack of them) are stated explicitly for
     two reasons. First, there is a tendency to view a written
     statement as ipso facto authoritative, and we hope to pro-
     mote the exchange and discussion of considerably less than
     authoritative ideas. Second, there is a natural hesitancy to
     publish something unpolished, and we hope to ease this
     inhibition." (Crocker, RFC 3 - 1969) [The entire RFC is
     reproduced in Appendix B.]

This openness led to the exchange of information. Technical
development is only successful when information is allowed to
flow freely and easily between the parties involved. These open
principles are what made the development of the Net possible.

     Statements like the ones contained in RFC 3 are very pro-
gressive in their openness. The late 1960's was a time alive in
popular protest for freedom of speech and people demanding more
of a say in how their country was run. The openness applied in
trying to develop new technologies fits well with the cry for
more democracy which students demanded throughout the country and
the world. What is amazing is that the collaboration of the NWG
(mostly graduate students) and ARPA (a component of the mili-
tary), seems to be contrary to the normal atmosphere of the
times. Robert Braden of the Internet Activities Board reflects on
this collaboration:

     For me, participation in the development of the ARPAnet and
     the Internet protocols has been very exciting. One important
     reason it worked, I believe, is that there were a lot of
     very bright people all working more or less in the same
     direction, led by some very wise people in the funding
     agency. The result was to create a community of network
     researchers who believed strongly that collaboration is more
     powerful than competition among researchers. I don't think
     any other model would have gotten us where we are today.
     (RFC 1336)

These ideas point to a reason why the work of these computer
scientists founded what has led to be one of the most amazing and
democratic bodies (i.e.: The Net and the culture attached to it)
to emerge in a long time. The community that has developed and
the tools which accompany it form an important democratic force.
[See endnote 5.]

     The idea of calling these notes a "Request for Comment" set
a fascinating tradition. It predates the Usenet Post, which in a
fashion could be called a "request for comment" as it is the
presentation of a particular person's ideas, questions or com-
ments, to the general public (of those who read that newsgroup)
for comments, criticism or suggestion, or just plain to further
the readers' knowledge. Other Early RFCs echo this reality. There
are plenty of RFCs which are in response to a previous RFC.
Following are some examples, more are contained in the appendix.

1    Crocker, S.  Host software   1969 April 7
65   Walden, D.   Comments on Host/Host Protocol document #1

36   Crocker, S.  Protocol notes  1970 March 16
38   Wolfe, S.    Comments on network protocol from NWG/RFC #36
39   Harslem, E.; Heafner, J. Comments on protocol re: NWG/RFC#36

33   Crocker, S.  New Host-Host Protocol  1970 February 12
47   Crowther, W. BBN's comments on NWG/RFC #33  1970 April 20


                      Part IV: Conclusion

     How were the developments of the ARPANET made possible? This
question appears from the very problems that the various contri-
butors to the ARPA project faced themselves. None of the partici-
pants had the solutions to any of the tasks they approached
before putting much thought and work into their research. As the
resulting ARPANET was tremendously successful and fulfilled the
project ARPA presented, it is important to see what can be
learned from the research out of which it emerged. Bernie Cosell,
who worked at BBN during this early period, describes the impor-
tance of openness in a developmental situation:

     *no*one* had the necessary expertise [and vision] to figure
     any of this out on their own. The cultures among the early
     groups were VERY different multics, sigma-7, IBM ... at
     Rand, ... PDP-10s at BBN and SRI... [and possibly] UCSB and
     Utah had pdp-10's, too. The pie-in-the-sky applications
     ranged over a WIDE landscape, with no one knowing quite
     where it would lead. Some kind of free, cross-cultural
     info/idea exchange *had* to happen. (Cosell 1993)

     The computer scientists and others involved were encouraged
in their work by ARPA's philosophy of gathering the best computer
scientists working in the field and supporting them:

     IPT usually does little day-to-day management of its con-
     tractors. Especially with its research contracts, IPT would
     not be producing faster results with such management as
     research must progress at its own pace. IPT has generally
     adopted a mode of management which entails finding highly
     motivated, highly skilled contractors, giving them a task,
     and allowing them to proceed by themselves. (ARPA draft,
     III-47)

     The work of the Network Working Group was vital to the
development of the ARPANET. Vint Cerf, another of the graduate
students involved with the early protocol development and still
closely connected to the Internet, echoed this sentiment when he
opened his paper "An Assessment of ARPANET Protocols," by writ-
ing:

     The history of the Advanced Research Project Agency resource
     sharing computer network (ARPANET) is in many ways a history
     of the study, development, and implementation of protocols."
     (Cerf, _An Assessment of ARPANET Protocols_)

Cerf supports Cosell's opinion about the uncertainty and newness
of the entire project when he continues in his paper by writing:

     The tasks facing the ARPANET design teams were often un-
     clear, and frequently required agreements which had never
     been contemplated before (e.g., common protocols to permit
     different operating systems and hardware to communicate).
     The success of the effort, seen in retrospect, is astonish-
     ing, and much credit is due to those who were willing to
     commit themselves to the job of putting the ARPANET togeth-
     er. (Cerf, IBID.)

     The NWG's work blazed the trail which the developers of the
TCP/IP suite of protocols (Transport Control Protocol/ Internet
Protocol) followed to success when the need to expand and include
other networks based on other technologies than NCP arose. The
principles embodied by RFC 3 and open RFC documentation provided
a strong foundation which began with NCP and was continued by the
work on TCP/IP. NCP was developed in the field and versions of it
were released early in its development so various programmers
could work on implementing and improving the protocol. In addi-
tion all specifications were available for free and easily
available for people to examine and comment on. Through this
principle of early release the problems and kinks were found and
worked out in a timely manner. The future developers of TCP/IP
learned from the developers of NCP a practice of developing from
the bottom up. The bottom-up model allows for a wide-range of
people and experiences to join in and perfect the protocol and
make it the best possible.

     The public funding of the ARPANET project allowed its
documentation to be open and available. This documentation was
neither restricted nor classified. The possibility of communi-
cation represented by openness was necessary for these pioneers.
Research of new fields of study require that researchers cooper-
ate and communicate in order to share their expertise with the
larger body of people conducting research. This openness is
especially critical when no one person has the answers in ad-
vance. Larry Roberts of ARPA explained in an article:

     "Since the ARPANET was a public project connecting many
     major universities and research institutions, the implemen-
     tation and performance details were widely published." ("The
     Evolution of Packet Switching", 267)

     The people at the forefront of development of these proto-
cols were the members of the Network Working Group, many of whom
came from academic institutions, and who therefore had the
support and time needed for the research. In summing up the
achievements of the process that developed the ARPANET, the
ARPANET Completion Report draft explains:

     The ARPANET development was an extremely intense activity in
     which contributions were made by many of the best computer
     scientists in the United States. Thus, almost all of the
     "major technical problems" already mentioned received con-
     tinuing attention and the detailed approach to those prob-
     lems changed several times during the early years of the
     ARPANET effort. [II-24]

     Fundamental to the ARPANET, as explained by the Completion
Report, was the discovery of a new way of looking at computers.
The developers of the ARPANET viewed the computer as a communica-
tions device rather than only as an arithmetic device. (draft,
III-24) This new view made the building of the ARPANET possible.
This view came from the research conducted by those in academic
computer science. The shift in the understanding of the role of
the computer is fundamental to advancing computer science. The
ARPANET research has provided a rich legacy for the further
advancement of computer science and it is important that the
significant lessons learned be studied and used to further
advance the study of computer science.


                           END - NOTES


1. This history is covered well in the article "From ARPANET to
USENET" by Ronda Hauben. Also in Chapter III, section 1.1.2
starting on page III-9 in the published ARPANET Completion
Report.

2. These quotes show some of the perspective chosen to pick the
initial ARPANET sites.

III - 689 "CCN's [The Campus Computing Network of UCLA] chance to
obtain a connection to the ARPANET was a result of the presence
at UCLA of Professor L. Kleinrock and his students, including S.
Crocker, J. Postel, and V. Cerf. This group was not only involved
in the original design of the network and the Host protocols, but
also was to operate the Network Measurement Center (NMC). For
these reasons the first delivered IMP was installed at UCLA, and
ARPA was thus able to easily offer CCN the opportunity for
connection."

pg II-16
"    In a somewhat less structured way, the research groups
receiving ARPA IPTO support were then encouraged to begin consid-
ering the design and implementation of protocols and procedures
and, in turn, computer program modifications, in the various host
computers in order to use the subnetwork. Several specific
responsibilities were arranged: UCLA was specifically asked to
take on the task of a "Network Measurement Center" with the
objective of studying the performance of the network as it was
built, grown, and modified; SRI was specifically asked to take on
the task of a "Network Information Center" with the objective of
collecting information about the network, about host resources,
and at the same time generating computer based tools for storing
and accessing that collected information. Beyond these two
specific contracts, some rather ad hoc mechanisms were pursued to
reach agreement between the various research contractors about
the appropriate "host protocols" for intercommunicating over the
subnetwork. The "Network Working Group" of interested individuals
from the various host sites was rather informally encouraged by
ARPA. After a time, this Network Working Group became the forum
for, and eventually a semi-official approval authority for, the
discussion of and "

III - 60   1.4.1.5 The Network Information Center

The accessibility of distributed resources carries with it the
need for an information service (either centralized or distribut-
ed) that enables users to learn about those resources. This was
recognized at the PI [ed. Primary Instigators] meeting in Michi-
gan in the spring of 1967. At the time, Doug Engelbart and his
group at the Stanford Research Institute were already involved in
research and development to provide a computer-based facility to
augment human interaction. Thus, it was decided that Stanford
Research Institute would be a suitable place for a "Network
Information Center" (NIC) to be established for the ARPANET. With
the beginning of implementation of the network in 1969, construc-
tion also began on the NIC at SRI."

3. The NAC was contracted by ARPA to "specify the topological
design of the ARPANET and to analyze its cost, performance, and
reliability characteristics. (ARPA, III-30)

4. RFC 1000 reports on the process of the installation of the
first IMP.
  "[T]ime was pressing: The first IMP was due to be delivered to
UCLA September 1, 1969, and the rest were scheduled at monthly
intervals.

     At UCLA we scrambled to build a host-IMP interface.  SDS,
the builder of the Sigma 7, wanted many months and many dollars
to do the job.
   Mike Wingfield, another grad student at UCLA, stepped in and
offered to get interface built in six weeks for a few thousand
dollars.  He had a gorgeous, fully instrumented interface working
in five and one half weeks.  I was in charge of the software, and
we were naturally running a bit late.  September 1 was Labor Day,
so I knew I had a couple of extra days to debug the software.
Moreover, I had heard BBN was having some timing troubles with
the software, so I had some hope they'd miss the ship date.  And
I figured that first some Honeywell people would install the
hardware -- IMPs were built out of Honeywell 516s in those days
-- and then BBN people would come in a few days later to shake
down the software.  An easy couple of weeks of grace.

   BBN fixed their timing trouble, air shipped the IMP, and it
arrived on our loading dock on Saturday, August 30.  They arrived
with the IMP, wheeled it into our computer room, plugged it in
and the software restarted from where it had been when the plug
was pulled in Cambridge.  Still Saturday, August 30.  Panic time
at UCLA.

   The second IMP was delivered to SRI at the beginning of
October, and ARPA's interest was intense.  Larry Roberts and
Barry Wessler came by for a visit on November 21, and we actually
managed to demonstrate a Telnet-like connection to SRI."

5. This democratic community is in danger of being fundamentally
altered. This study of the history of the development of the
ARPANET in conjunction with my paper, "The Social Forces Behind
the Development of Usenet News" are meant to help people under-
stand where the Net has come from, in order to defend it, and try
to fight to keep it open and democratic - the seventh wonder of
the world as a recent ad called the Internet, misdirected as it
was - but correct any way. I hope to make this analysis available
in RFC form as a comment on RFC 1000.


                          Bibliography

Special Thanks to Alexander McKenizie of BBN, Stephen Crocker of
TIS, and Vinton Cerf of CNRI for making research materials available.

ARPANET COMPLETION REPORT DRAFT , September 9, 1977, unpublished.

Cerf, Vinton G., private corespondence, dated Nov 27, 1993.
     Subject: "Re: Early Days of the ARPANET and the NWG"

Cerf, Vinton G., "An Assessment of ARPANET Protocols."  Infotech
     Education Ltd. Stanford University, California, 21 pages

Cosell, Bernie "Re: RFC1000 - Questions about the origins of
     ARPANET Protocols 2/2" Article: 54310 of
     alt.folklore.computers, Nov. 23, 193.

Crocker, Stephen D., 1993A email message to Com-Priv mailing list
     ([e-mail]) Subject "Re: RFC1000 (Partial response to
     part 1)" Date: Nov 27, 1993.

Crocker, Stephen D., 1993B email message to Com-Priv mailing list
     Subject: "Re: RFC1000 (End of response to part 1)"
     Date: Nov 27, 1993.

Crocker, Stephen D., 1993C email message to Com-Priv mailing list
     Subject "Subject: Re: RFC1000 (Response to part 2)"
     Date: Nov 27, 1993.

Crocker, Stephen D.,  RFC 3, DOCUMENTATION CONVENTIONS.

Crocker, Stephen D.,  RFC 1000, RFC Reference Guide.

Heart, F, McKenzie, A., McQuillan, J., Walden, D., ARPANET
     Completion Report, Washington, 1978.

Licklider, J.C.R., Interview conducted by William Aspray and
     Arthur Norberg on October 28, 1988 Cambridge, Mass. CBI Univ
     of Minn., Madison.

Licklider, J.C.R. and Robert Taylor, "The Computer as a Communi-
     cation Device" from "In Memoriam: J.C.R. Licklider
     1915-1990," Aug. 7, 1990, p. 40; reprinted by permission
     from Digital Research Center; originally published as "The
     Computer as a Communication Device," in "Science and Tech-
     nology", April, 1968, pg. 40

Mckenzie, Alexander, Interview with Nov 1, 1993.

Roberts, Lawrence Member IEEE, Invited Paper, "The Evolution of
     Packet Switching", Proceedings of the IEEE Volume 66, Number
     11, November 1978, pages 1307 - 1313

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