[3] [Editor's Note: In honor of the 30th Anniversary of TCP/IP we print
the following history of the international collaboration that make TCP/IP
possible.]
The Internet: On its International Origins and Collaborative Vision
(A Work In Progress)
by Ronda Hauben
rh120@columbia.edu
"[T]he effort at developing the Internet Protocols was international
from the beginning."
Vinton Cerf, "How the Internet Came to Be"
ABSTRACT
The process of the Internet's development offers an important
prototype to understand the creation of a multinational
collaborative research project which depends on and fosters
communication across the boundaries of diverse administrative
structures, political entities, and technical designs.
The mythology surrounding the origins of the Internet is that it began in
1969 in the U.S. That is the date marking the origins of the ARPANET (a
U.S. packet switching network), but not the birth of the Internet. The
origins of the Internet date from 1973.
The goal of the researchers creating the Internet was to create a network
of networks, a means for networks from diverse countries to inter-
communicate. Originally the design was to link up several national but
diverse packet switching networks including the ARPANET (U.S.), Cyclades
(France), and NPL (Great Britain). When that was not politically feasible,
the research project involved Norwegian, British and American research
groups, and researchers from other countries, especially France, at
various junctures. These research groups did the early development work.
The Internet was international from its very beginnings.
Preface
The following work in progress begins the investigation of the
collaboration between researchers from the U.S. and several European
countries in the early development of the Internet. Both Bob Kahn and Vint
Cerf, Internet researchers who are credited with the invention of the
TCP/IP protocol, have noted that the Internet was international from its
very origins. Yet the common understanding of the development of the
TCP/IP protocol, the protocol that made it possible to build the Internet,
has been that it was an American development. This misconception prevents
the development of an accurate public understanding of the origins of the
Internet, and of the lessons that this early history can provide for the
future. It is impossible to have achieved the development of an
international network of networks, of the Internet, without the
international participation and collaboration to build the prototype and
the functioning implementations of the needed technology.
This hidden history involved researchers from Great Britain, France,
Norway, Germany and Italy, and the U.S. Recently I have also learned of
the knowledge and interest in computer networking of researchers in
Eastern European countries including Hungary, Russia and German Democratic
Republic. How the actual historical development unfolded cannot be known
unless there is serious attention to this research while pioneers of these
achievements are alive and can be interviewed and encouraged to provide
the help they can give. In the following working draft I begin to document
some of the links and events that have come to the fore. I hope this
working draft will begin the discussion needed to raise some of the
research questions involving the Internet's origins that need scholarly
collaborative attention, especially while the Internet pioneers are
still
alive.
I - Introduction: How Will the History of the Internet Be Told?
In a review essay in the December 1998 issue of the American Historical
Review, the author, Roy Rosenzweig, points to how rarely most histories of
the 20th century mention either computers or the Internet. Rosenzweig,
however, predicts that this will soon change. He writes:
It is a fair guess that textbooks of the next century will devote
considerable attention to the Internet and larger changes in information
and communication technologies that have emerged so dramatically in
recent years.
Then he asks the question, "How will the history be written?
Discussing several recent books about the history and development of the
Internet, Rosenzweig suggests that no one single account is sufficient;
that there will need to be a more adequate history written which will
include aspects of all the books.
The review raises the question of what is needed to write the history of
the Internet. It also considers whether the books already written meet the
challenge or if there are essentials left out that can be investigated and
documented.
Several of the books that have been written thus far focus mainly on the
development of the ARPANET.(1) The ARPANET was an important predecessor to
the Internet. It is the network that demonstrated to the world that large
scale packet switching would be a feasible form of computer communications
technology. Describing the ARPANET's contribution to the development of
the Internet, Robert Kahn, co-inventor of the TCP/IP protocol explains:
"The ARPANET was helpful in that it demonstrated the power of networking
even though for a single network and community. The kinds of things that
happened there, happen in all kinds of networks and communities. It also
showed the importance of protocols and introduced an example of protocol
layering (e.g. FTP on top of NCP on top of the communication subnet.)"
(Kahn, E-mail, September 15, 2002.) This new technology made possible the
resource sharing of human and computer resources.(2) This background helps
to understand the origins of the Internet.
The history of the ARPANET and of packet switching, however, is not the
history of the Internet. The ARPANET was a single network that linked
heterogeneous computer systems into a resource sharing network, first
within the U.S., and eventually it had tentacles to computer systems in
other countries.(3) The ARPANET also supported the sharing of human
resources and enabled people to interact. But the computer systems had to
meet certain requirements, including permission from the U.S. government
to connect to the ARPANET. The history of the ARPANET is the history of
some of the foundations for the Internet. But it is not the history of the
Internet. "What the ARPANET didn't address," Kahn clarifies, "was the
issue of interconnecting multiple networks and all the attendant issues
that raised." (Kahn, E-mail, September 15, 2002)(4)
II - Purpose
This paper is a beginning study of the origins, international in scope, of
the Internet, and of the technology that made the Internet possible. This
was the development of the TCP/IP protocol. The purpose of the paper is
three fold. The first is to distinguish between the ARPANET and the
Internet. In order to look at the origins and development of the Internet,
it is important to recognize that the Internet is the solution to the
multiple network problem, whereas the ARPANET and other packet switching
networks were the solution to an earlier problem: the problem of
communication among dissimilar computers and operating systems.(5)
Second, this paper documents the international collaboration and
participation to create and develop the Internet that could span national
borders and interconnect the computer communications networks of different
countries. This collaboration involved the U.S., Norway and the U.K. and
researchers from France and then Germany and Italy, at different stages in
the process. Creating an Internet was a difficult problem to solve, not
only theoretically, but practically as well. To understand the nature of
the Internet, it is necessary to understand the multiple network problem
and how it was solved. The difficulties were not only technical.
Describing some of the difficulty he encountered, a British Internet
pioneer, Peter Kirstein writes, "I was certainly ordered, in 1976, to stop
work on the Internet Protocol but to concentrate only on European
developments. I refused, and pursued several alternate paths for at least
another decade." (Kirstein, E-mail, October 4, 2002.)
Third, a central aspect in the development of the Internet is the vision
that inspired and provided the glue for the international collaborative
research efforts. To explore the nature and origin of this vision helps to
understand the research processes creating the TCP/IP protocol.
III - Packet Switching Networks
Early research efforts to develop a way of transporting computer data led
to the development of what is called "packet switching". Packet switching
technology breaks a message into small sections of data, gives each of
these addressing information called a header, which together with the data
are called "packets". It then routes and delivers the packets, inter-
spersed with other packets from other messages. After the packets reach
their destination, the message is reconstructed. Paul Baran in the U.S.
and a few years later, and unaware of Baran's work, Donald Davies in the
U.K., developed similar concepts. In 1966 Davies implemented a packet
switch connecting a set of host computers. Paal Spilling, a Norwegian
Internet pioneer, refers to the resulting National Physical Laboratory
(NPL) network as the first packet switching local area hub network.
(Spilling, E-mail, August 2002)
In the U.S., there was interest in exploring the feasibility of packet
switching for resource sharing computer networks. This interest led the
Advanced Research Projects Agency (ARPA) to recruit Larry Roberts, a
researcher at MIT's Lincoln Laboratories to join the Information
Processing Techniques Office (IPTO). IPTO was planning to establish a
packet switching network interconnecting a number of geographically
dispersed dissimilar computers.
Networking technology was also of interest to other researchers around the
world. In the early 1970s in France, Louis Pouzin was developing a French
packet switching network, building on the lessons learned from previous
packet switching research. He studied the research developments in the
U.S. and Great Britain, and along with his research group, created the
Cyclades/Cigale network. In the U.K., the NPL network was being developed
by a research group headed by Donald Davies. In the U.S., there was the
ARPANET development. The question became how could these networks be
interconnected, i.e. how would communication be possible across the
boundaries of these dissimilar networks. (Ronda Hauben, "The Birth of the
Internet")
A plan at the time was to connect the ARPANET in the U.S., CYCLADES, in
France and NPL in Great Britain. A memo written in 1973 describing early
technical plans for this interconnection, included a diagram of these
three networks linked by gateways. These gateways would make it possible
to transmit messages across the boundaries of different constituent
networks. Following is a replica of the diagram (Cerf, Memo, p. 5. See
Also Graphic I):
(Host)
/
( ) ( ) ( )
( ) ( ) ( )
(Host)-(CYCLADES)--(gateway)--( ARPA )--(gateway)--( NPL )
( ) ( ) ( )
( ) ( ) ( )
\
(Host)
Also there was a diagram of data going from a host computer on one
computer network to a gateway and then to a host on another computer
network.
(H)----(G)----(G)---(H)
\ /
\ /
(H)
Another description of the goal of connecting these 3 different networks,
is presented at the International Institute for Applied Systems Analysis
(IIASA) in Laxenburg, Austria, in 1974. In a paper for a conference there,
British researcher, Donald Davies writes:
To achieve... the interconnection of packet switching systems we have to
decide at what level they will interwork. The levels chosen could be
character stream, packet transport or the virtual circuit. After some
discussion, a group including ARPA, NPL, and CYCLADES is trying out a
scheme of interconnection based on a packet transport network with an
agreed protocol for message transport....
(Davies, "The Future of Computer Networks", IIASA Conference
on Computer Communicatio Networks, October 21-25, 1974, p. 36)
Davies' paper is helpful in documenting the interest in creating a
meta-network of other networks including the ARPANET, NPL and CYCLADES.
Also, however, the occasion of the paper is significant. The IIASA is a
research institute which supported collaboration among researchers from
the Soviet Union and Eastern European countries and from the U.S., Western
Europe and Japan. The conference in 1974 at which Davies spoke was a
conference where researchers from these different countries were all
introduced to networking technologies and developments of the time,
including the ARPANET, NPL and CYCLADES developments.
At a workshop the following year in Laxenburg, in 1975, sponsored jointly
by the IIASA and also the International Federation of Information
Processing Organizations (IFIP), another British researcher, Peter
Kirstein presented a paper that described the collaboration between the
U.K. and the U.S. in networking. The paper included a diagram of the
satellite and ground connectivity between the ARPANET in the U.S. and the
University College London, (UCL) computers in U.K. The diagram also showed
the Norwegian connection to the U.S. and U.K. networks. Kirstein's paper,
"The Uses of the ARPA Network via the University College London Node" was
reported to have been exciting to those present and plans for a network
connecting the researchers of the IIASA were developed. The list of those
at this workshop included researchers from Austria, Belgium, France, the
Federal Republic of Germany, the German Democratic Republic, Hungary,
Italy, Netherlands, Poland, Switzerland, the Soviet Union, the U.K., and
the U.S. Davies and Kirstein were there from the U.K., Cerf from the U.S.,
Lazzori from Italy. Kopetz from Austria, K. Fuchs-Kittowski from the
Germany Democratic Republic. Also there was discussion at the workshop
about what kind of network researchers the IIASA would develop to support
their collaboration.
The IIASA conference in 1974 and the workshop in 1975 include reports on
the networking research being done to create the Internet and other
networks like the European Informatics Network (EIN). It is significant
that at a group including researchers from both Eastern Europe, the U.S.
and Western Europe, the details of the internetworking developments were
presented and discussed. Fuchs-Kittowski, a researcher from the GDR
present at the 1975 workshop, remembers discussing possible participation
in the UCL network in the U.K. by those from the German Democratic
Republic. (See for example, Graphic III) There is at least one discussion
in 1976 about whether or not to have an IIASA connection to the ARPANET or
to the EIN. There was also international collaboration as part of the IFIP
6.1 working group toward the development of the Internet.
There are various streams of research that made contributions to the
development of the Internet. The researchers in France developing
Cyclades/Cigale contributed the important concept of the datagram as a
means of transporting data. Pouzin also is credited with the creation of
the sliding window as a flow control mechanism.(6) There were discussions
among those participating in the INWG, later called IFIP, WG 6.1, where
decisions were considered about what the standards should be to create the
protocol for an Internet. For example, Pouzin describes some of the
meetings:
Within INWG, which joined IFIP as WG 6.1, we had lengthy discussions
about which level of protocol should be agreed first. It must have been
during an INWG meeting on a boat (Stockholm-Turku and return) that a
consensus developed on the principle of a common packet format. I don't
have a record of this meeting in my diary, but I gather it was in August
1974, at the time of an IFIP Congress. (Pouzin, E-mail, April 28, 2003)
Pouzin was also at the INWG 1974 conference and describes some of the
discussion there. He writes:
Yes, this was 21-24 October 1974. We kept refining a common packet
format. I had cranked up a proposal overnight during the workshop, and I
remember Peter Kirstein made some objections after a call to Vint Cerf
in the U.S. I don't know if this paper was recorded in history, perhaps
as an INWG note. (Pouzin, E-mail, April 28, 2003)
Describing the efforts that were made to link Cyclades and NPL, Pouzin
explains:
In the end, there never was an interconnection based on this plan. What
occurred was a demo during an ICCC conference in Toronto, 3-5 August
1976. There was a Cyclades terminal concentrator (like a TIP) connected
to Paris with a leased phone line. There, a link to NPL was using the
packet network EIN (alias Cost 11), (if I remember). Then at NPL it was
connected to the internal local net.
On the exhibit in Toronto, Derek Barber demonstrated using an NPL host
through this patchwork. I felt it was amazing, if rather intricate.
Another more elaborate attempt was the definition of a protocol subset
allowing a TCP-IP host to talk to a Cyclades host, without a gateway,
simply by using a restricted set of protocol features. This work was
carried out by Alex McKenzie from BBN. He wrote an INWG note. Maybe
someone has a copy! Presumably, there was not enough steam, and money,
to implement the idea. (Pouzin, E-mail, April 28, 2003)
IV - Great Britain and the U.S. Plan to Collaborate
As early as the end of 1970, there was discussion between American and
British research groups on how to link the U.S. and U.K. networks
together. One plan was to utilize the connection between the U.S. and
Norway connecting the NORwegian Seismic ARray (NORSAR) near Oslo to the
U.S. Describing this discussion, Peter Kirstein of the University College
London (UCL)(7) writes:
In late 1970, Larry Roberts proposed to Donald Davies that it would be
very interesting to link their two networks together. The existence of
the Washington to NORSAR line would make it comparatively cheap to break
the connection in London and link in the NPL network. There were two
problems with this plan; first of all we underestimated the tariff
implications of adding the extra drop-off point; secondly, the timing
could not have been worse from a British national perspective. The
problem was that the British government had just applied to join the
European Community; this made Europe good and the U.S. bad from a
governmental policy standpoint. NPL was under the Department of
Technology and Donald was quite unable to take up Larry's offer. He had
to concentrate on European initiatives like the European Informatics
Network (EIN). In the meantime, I had been interested in the ARPANET
from the beginning; it was therefore agreed early in 1971, that we would
attempt to set up a project link in UCL instead of NPL.
(Kirstein, E-mail, July 3, 2002)
Through discussion between the U.K. and IPTO researchers, an agreement was
reached for a research collaboration. Larry Roberts, according to
Kirstein, "agreed to provide a Terminal Interface Message Processor (TIP)
for the project, valued at 50,000 pounds, and to allow us to use the very
expensive existing transatlantic link. It was merely for the U.K. to
provide any manpower and travel costs needed to complete the project, and
to provide the (assumed modest) cost of breaking the communications link
in London.... By the end of 1971, the technical proposal was complete."
(Ibid.)
Kirstein describes how he struggled through most of 1972 trying to get
funding support from the British government without success. "These
machinations," he notes, "took most of 1972, and by the end of that
period, the situation looked hopeless. Neither the SRC (Science Research
Council) nor the DOI (Department of Industry) would supply any finance."
(Ibid.)
Also the situation had changed with regard to the Washington to NORSAR
link. "The Scandinavian Tanum Earth Station in Sweden had come on-stream,"
writes Kirstein. "As a result the U.S. Norway connection no longer passed
through the U.K. Hence a new 9.6 kbps link between London and Kjeller was
needed; the cost of this link was going to be very expensive." (Ibid.)(8)
Fortunately, the British Post Office (BPO) and NPL, two British government
organizations, came through with the promise of support. Kirstein
continues(9):
Two senior directors of the BPO, Murray Laver of the National Data
Processing Service, and Alec Merriman of Advanced Technology, agreed to
provide the finance for the U.K. Norway link for one year. In addition,
Donald Davies agreed to promise the most he could sign for personally,
(5000 pounds). With these two modest contributions, I told Larry Roberts
that we would proceed. (Ibid.)
Even with this support, however, Kirstein was faced with a difficult
working environment in the U.K. He writes:
It would be nice, in retrospect, to have called it a British decision;
it was not. There was grudging support, and the main research
initiatives were in pursuit of the X.25 protocol suite and its upper
levels. There was almost no European activity on the Internet Protocols
outside Oslo and UCL. (Kirstein, E-mail, October 4, 2002)
V - U.S. and Norwegian Collaboration is Arranged
While these negotiations between UCL and IPTO were ongoing, IPTO invited
Norwegian researchers to collaborate on resource sharing network research.
After an invitation to the Norwegian Telecommunications Administration
(NTA) did not generate interest, the IPTO extended an invitation to the
Norwegian Defence Research Establishment (NDRE, "Forsvarets
Forskningsinstitutt").
NDRE welcomed the proposed collaboration. According to Yngvar Lundh, one
of the Internet pioneers in Norway, NDRE's interest in basic computing and
networking research was the reason for the Norwegian collaboration with
IPTO.(10)
On September 18, 1972, Larry Roberts and Robert (Bob) Kahn visited Norway,
meeting with Lundh, then a research engineer at NDRE, Finn Lied, the
director of NDRE, and Karl Holberg, the research superintendent of the
NDRE electronics department. (Lundh, E-mail, April 24, 2002) Lundh had met
Roberts several years earlier during Lundh's sabbatical in 1958-9 as a
visiting researcher. He was at MIT's Electronics Systems Lab where Roberts
was a graduate student finishing up his PhD. They were both using the
TX-0.(11)
Lundh recalls that the meeting with the visitors from IPTO was held in
Oslo at a civilian research administrative office at the Royal Norwegian
Council for Scientific and Industrial Research. Also at the meeting were
representatives from other Norwegian organizations. (Lundh, E-mail, April
26, 2002.) In a history in Norwegian of the role of Norway in early
Internet development, Gisle Hannemyr writes that Lundh saw the
collaboration with IPTO as "an opportunity to further advance data
communication research in Norway." (Hannemyr, E-mail, his translation)
Roberts and Kahn invited NDRE to collaborate and recommended they send
researchers to the first International Computer Communications Conference
(ICCC'72) planned for October 1972 in Washington, DC. There was to be a
demonstration of the resource sharing packet switching network that was
being developed in the U.S. Describing the importance of this event,
Donald Davies writes:
The meeting at the Washington Hilton in 1972 was quite the most
important and influential conference I have ever attended.... I arrived
at the Hilton Hotel early to see what was happening and met an
extraordinary scene. On a podium was 'Terminal IMP' or TIP ... joined
to the existing ARPA network, surrounded by many terminal devices of all
kinds.
The astounding thing was a crowd of young, enthusiastic researchers who
were rushing around or huddled in earnest discussions trying to get
everything to work. Listening to their conversation we heard all that we
had been trying to promote for the previous 5 years being talked about
as self evident � a new and strange experience. Most of all, one had the
impression of a great amount of intellectual effort now being applied to
computer networking, which must grow in importance.
It was a complete turn-around, seemingly in one day, though in fact it
was the enormous efforts of the ARPA team that achieved this
demonstration and caused the revolutionary change in thinking about
networks.
It completely changed attitudes to computer communications. Yet, many of
the ideas it fostered had been talked about for five years or more. What
happened in Washington was that people could now see these ideas in the
form of practical achievements. They could get a glimpse of the
intellectual impact that networks were destined to produce.
(Donald W. Davies, "Early Thoughts on Computer Communications")
Lundh writes that he attended the ICCC conference on October 25 and 26,
1972. While at the demonstration, he was invited to attend a meeting with
other networking researchers from around the world held after the ICCC'72
at the Comsat Corporation (at L'Enfant Plaza). He writes that this meeting
"may well have been the first Internet meeting." (Lundh, E-mail April 26,
2002) This was also the meeting where the International Network Working
Group (INWG) was created. Lundh reports that at the meeting at Comsat,
"The discussion(s) were in rather general terms as I recall, and mainly
clarifying reasons for establishing a net of nets where each individual
net would use the best low level protocol for utilizing the respective
transmission. He estimates that there were 10-15 people there that day.
Certainly Bob Kahn and most likely Dick Binder from BBN." (Lundh, E-mail,
June 24, 2002) Kirstein notes that he was there. Cerf adds that he was
there, along with Steve Crocker from ARPA, Louis Pouzin, Gesualdo Lemoli,
Roger Scantlebury and perhaps Donald Davies. Also Kirstein presented a
paper at the ICCC'72 conference.(12)
Although the research proposed by IPTO was new to him, Lundh found "the
ideas interesting and accepted the invitation to participate in the
development." (Lundh, E-mail, April 9, 2002) To actively participate in
the research, he built "a small group of researchers which became one of
ten groups which took part in basic Internet research during a ten year
period from 1972." (Lundh, E-mail, April 9, 2002) He was frustrated,
however, trying to muster resources and was hoping for some assistance
from ARPA. But he also realized that it was difficult for IPTO to help
fund the Norwegian researchers. (Lundh, E-mail, July 12, 2002)
Lundh reports, "I had no financial support in the beginning, but I
formalized a small 'job' called 'Radio Data Systems-RADA' at NDRE with the
purpose (of) fitting in with ARPA's resource sharing (research)." In the
beginning of the collaboration, Lundh had to support the travel and the
research he did in his spare time with other projects he was working on.
For the first few years, he recalls, he had help from two graduate
students whose thesis work he was supervising.
The ARPANET TIP was not put at NDRE which was in a military area with
restricted, and thus, limited access. Instead it was placed in NORSAR's
building which was on the other side of the fence from NDRE. Lundh
explains that "seismic array technology or test detection was not NDRE's
reason for placing the NDRE TIP at NORSAR.(13) It was a practical
arrangement for us, and probably a convenient arrangement for ARPA too."
(Lundh, E-mail, April 18, 2002) The TIP at NORSAR was thus at a civilian
facility, providing access for more widespread Norwegian participation in
networking research and facilitating academic collaboration in
networking.(Lundh, E-mail, April 18, 2002)
A problem the Norwegian group faced, according to Lundh, was that it was
difficult to build a research team given the lack of funding. "It was hard
to convince Norwegian financing sources of the importance of computer
networking," Lundh writes. (Lundh, 18) He was excited by the concept of
resource sharing. "My reasons for wanting to participate were that I
intuitively thought the possibilities of resource sharing were fantastic."
Lundh elaborates, "I saw 'resource sharing' as (providing -ed) interesting
possibilities in several 'dimensions', resources being expensive programs,
special data, ideas, people with various interests and capabilities, etc."
(Lundh, E-mail, July 12, 2002) Despite these funding difficulties, the
Norwegian research group made an important contribution to the development
of TCP/IP and the Internet.
VI - How to Communicate Across Network Boundaries?
Shortly after the successful ICCC'72 conference, Bob Kahn left his job at
Bolt Beranek and Newman (BBN) and went to work at IPTO. Joining IPTO as a
program manager, Kahn initiated certain projects and also took over
responsibility for one that had already been funded. A new initiative was
to create a ground based packet radio network. An existing initiative was
to create a satellite-based packet switching network. (Ronda Hauben, "The
Birth of the Internet", p. 7)
The ground packet radio network would be of particular interest to the
U.S. Department of Defense (DoD), as it would make packet switching
computer networks possible in otherwise difficult to reach areas or
conditions. Kahn's objective was to create a multinode ground packet radio
network (PRNET) where each node could be mobile. In parallel, he sought to
create a packet satellite network (SATNET) utilizing INTELSAT
satellites.(14) The goal of the packet satellite network research was to
make resource sharing computer communications networking possible with
different European sites. Two of the networks (PRNET and SATNET) would use
radio transmission and the third network which already existed (ARPANET)
used shared point to point leased lines from the telephone company. Though
Kahn originally considered the possibility of seeking changes to each of
the constituent networks to solve the multiple network problem, he soon
recognized the advantage of an architecture that would directly
accommodate a diversity of networks. To join an existing network like the
ARPANET would require another network to become a component of it. Kahn
conceived that there was a need for an architectural conception that would
allow the communicating networks to function as peers of each other,
rather than requiring that any one become a component of another. He saw
there was a need to design an architecture that would be open to all
networks, an architecture that Kahn called "open architecture".(15)
VII - Designing Protocols and Specifications for an Internet
Once at IPTO, Kahn invited Vinton (Vint) Cerf to collaborate with him.
Kahn wanted to design an open architecture protocol and needed Cerf's
knowledge of computer operating systems to do it. Other researchers were
also interested. For example, at an INWG meeting in June, 1973, in New
York City, Kahn and Cerf were joined by E. Aupperle, R. Metcalfe, R.
Scantlebury, D. Walden and H. Zimmerman. Scantlebury was from the U.K. and
Zimmerman, from France. Others listed were members of the U.S. network
research community. The document also credits G. Grossman and G. LeLann
for contributing after the meeting. LeLann was from France. (INWG note #39
NIC # 18764, dated 9-13-73). Cerf explains that LeLann worked with Louis
Pouzin at IRIA (now INRIA) and "spent 6 months working with me and others
on the design of the Internet's TCP protocol." (Cerf, E-mail, April 13,
2003) Pouzin also remembers a June 1973 INWG meeting, noting that it was
quite hot in NYC. (Pouzin, E-mail, April 28, 2003)
The INWG note #39 is a draft paper that Kahn and Cerf prepared for
presentation at the September 16, 1973 INWG meeting in Brighton, England.
A revised draft of the paper was published in May, 1974, titled "A
Protocol for Packet Network Intercommunication" in the IEEE Transactions
on Communications. The paper describes the philosophy and design for the
TCP/IP protocol, though the original paper called the protocol TCP, as the
IP function was originally embedded in TCP.(16)
After designing a protocol, there is a need to write specifications to
implement the design. (16a) Cerf refers to the development of two versions
of the specifications for TCP developed at Stanford University, one in
December 1974 and a second in March 1977. Subsequently two further
specifications were developed with other groups.(Cerf) Among the names of
those working on the initial specifications for TCP, Cerf lists U.S.
researchers or graduate students including Y. Dalal, C. Sunshine, R. Karp,
J. Estrin, and J. Mathis, at Stanford; R. Tomlinson and W. Plummer, at
BBN; R. Metcalfe, D. Boggs, and John Schoch, at Xerox PARC. He also lists
several researchers from the U.K., from UCL, F. Deignan, C. .J Bennett, A.
.J Hinchley and M. Gallard. Cerf also thanks G. LeLann from the University
of Rennes, France. Cerf writes that Dag Belsnes, from the University of
Oslo, Norway provided "additional philosophical leavening which influenced
the design of the protocol."(Cerf, The Final Report, IEN 151, 2)
When asked what he thought the term "philosophical leavening referred to,"
Belsnes responded, "I also wonder what 'philosophical leavening' is
referring to. Perhaps that I always like to discuss and establish some
understanding of problems."(17)
In 1973, Belsnes received a one year grant from the Norwegian Research
Council. After meeting Vint Cerf at a conference in England in 1973,
Belsnes contacted Cerf and was accepted to be part of the research effort
at the Digital System Laboratory at Stanford University. "I got the
opportunity," Belsnes writes,
to participate in his Protocol Design Group that worked on creating a
specification for the Internet Transmission Control Program. Belsnes
explains that among his main interests were "protocol correctness and
flow congestion control. (Belsnes, E-mail, June 17, 2002)
Creating a design and then specifications for the development of a
protocol for internetworking is a significant step. It is, however, part
of a larger research process. Elaborating on the value of the experimental
work, Paal Spilling, another of the Norwegian Internet pioneers, writes:
A group at Stanford University (SU) specified in detail a control
program ... the Transmission Control Program (TCP) allowing computers in
different inter-connected networks to communicate.... Although the TCP
was specified in detail, it had to be considered as a first approach
towards making a reliable process-to-process communication tool in an
internetwork environment. Experience showed that this was the case....
The results obtained, helped in the debugging of this first version of
the TCP, and uncovered some deficiencies in its design. Some of these
could be taken care of rather easily, while others were subjects for
further investigations. (Spilling, Proposal to NATO)
Kahn had recognized the need to include at least three different kinds of
packet switching networks to test if the protocol created for inter-
communication among dissimilar networks would be adequate. If a prototype
has only two different entities, it is difficult to tell what is
particular about each and what is general about the two. With three or
more dissimilar networks as part of a prototype, it is possible to
identify what is general to them all despite the dissimilar nature of
each.
In June 1973, a TIP was installed at Kjeller, Norway for the NDRE
researchers. By the end of July 1973, the UCL TIP in the U.K. was also
passing packets between the U.S. and U.K. These packets went from the U.S.
via satellite to the Tanum Earth Station in Sweden, via land and
underwater lines to NORSAR in Sylvia, Norway, and then to London in the
U.K. Kirstein and Kenny provide a diagram of the relation between the U.K.
TIP, the Norwegian TIP and the U.S. ARPANET.(18)
Kirstein writes that one of the significant activities in the early work
to develop the Internet was "an early protocol experiment in late 1974
between a junior assistant professor at Stanford (Vint Cerf) and a
visiting scholar from Norway at UCL (Paal Spilling) of the Proposed
Transmission Control Protocol." Spilling, visiting UCL from NDRE, worked
with Kirstein's research group. Judy Estrin was a graduate student working
with Vint Cerf at Stanford. Estrin and Spilling "did what was probably the
first TCP tests with each other. They were independent implementations,"
Kirstein explains. (Kirstein, E-mail, May 20, 2002.) Describing this
research, Spilling elaborates, "As I remember the fellows at the Stanford
side may have been Judy Estrin and Jim Mathis. At the UCL side were Frank
Deignan, Andrew Hinchley and me. Frank was the implementer. It was
extremely exciting to observe packets coming from Stanford and after an
initial debugging being accepted and processed by Frank's implementation
of TCP. One critical problem I can remember was that the TCP checksum was
applied slightly differently at Stanford and at UCL." (Spilling, E-mail,
August 1, 2002)
Kirstein describes how the British government became more supportative of
his research by 1975. He writes: "The British authorities became
increasingly positive from 1975. I had set up a management committee to
oversee the use of the ARPAnet link. This included representatives from
the British Post Office, the Ministry of Defence, the Science Research
Council and the Department of Industry. They had to approve all requests
for usage. From 1976, there was increasing pressure for using the emerging
X.25 infrastructure (International Packet Switched Service � IPSS) as an
alternative to SATNET. First this involved a commercial 9.6 Kbps line from
about 1978 between UCL and BBN; here it was necessary to arrange the link
so that no commercial charges would arise to BBN and DARPA. Later, I think
it was around 1980, a 64 Kbps IPSS link was provided also free of charge
by the British Post Office. This link existed until around 1984, and
allowed much fuller research into multiple routes with different capacity,
charging and access control considerations. The IPSS link was always using
IP; for this reason the multiple use of the commercial use and SATNET was
an important landmark into the use of interconnected networks. It was
their existence which allowed UCL to adopt a phased approach to the
adoption of the Internet Protocol. We first proved it on the IPSS link
without affecting NCP traffic on SATNET; this needed NCP-TCP relays at UCL
and BBN. We could then move it onto SATNET, without impacting too
drastically our service traffic � which could use the IPSS route in an
emergency. Finally, when the ARPANET had moved to Internet Protocols, we
could abandon our relays in BBN and also leave SATNET; all the traffic
could use IP/X.25 over IPSS. It is the phased nature of this transition
which explains why UCL finally left SATNET (see below) after the
Norwegians though they used IP for service traffic much earlier."
"By the time we got to around 1983, complete alternate mail nets, like
UUCP and BITNET started coming into being. The various gateways these
provided gave a much richer topology. When the DNS was added, its impact
on the international infrastructure was not realised at first. When we
introduced blocking on some of our IPSS routes, we suddenly realised the
magnitude of international traffic that was passing over the U.K.-U.S.
routes originating from these other networks. It was then that the work on
peering and service agreements took on a new urgency for these data
networks." (Kirstein, E-mail, October 8, 2002)
VIII - Early Norwegian Internet Research Challenges
During its earliest stage, Lundh's research group consisted of his 2
graduate students and himself. By 1974 he was able to get Paal Spilling
assigned to his group, Spilling had a PhD in nuclear physics and was
interested in the networking project. Subsequently other qualified
engineers were assigned by NDRE to the research group. Lundh describes the
change Spilling's participation made in the NDRE research group. He writes:
Paal Spilling came to my group in 1974.... I recruited him from one of
my colleague's group(s) at NDRE where he had become superfluous. At that
time I had good contact with people in PSP and INWG. I participated in
their meetings and knew Peter Kirstein. They were all delighted that I
finally got someone beside me. And - as I recall - Peter offered to have
him at UCL for a couple of months to give a flying start, which was very
good and useful indeed. Paal soon got the whole networking business
'under his skin' and after that participated together with me in all the
meetings. He soon became the main contributor to the networking effort
at NDRE, for some time being the only one who spent full time in it.
(Lundh, E-mail, June 12, 2002)
Lundh emphasizes that the continual invitation to the Norwegian
Telecommunications Administration Research Establishment (NTA-RE) to
participate in the research led to "the free loan for experimental
purposes of a spare channel in the INTELSAT IV satellite and a spare line
between NDRE and the existing Scandinavian Satellite Earth Station at
Tanum, Sweden. This permission was obtained in 1975 permitting the SIMP -
Satellite IMP - to be installed at the Tanum Station in mid 1975. From
then on SATNET had three ground stations permitting experiments involving
contentious traffic situations. Mario Gerla in Leonard Kleinrock's group
at UCLA was very active in the SATNET studies which eventually resulted in
the CPODA-protocol for Contention Priority Oriented Demand Access."
(Lundh) According to Lundh, other researchers in Norway were not eager to
use the NORSAR TIP during the 1970s. But interest was expressed by the
staff at NORSAR in utilizing the ARPANET as an alternative to the channel
they had for exchanging seismic data with the U.S. Lundh notes that
"Commercial traffic was prohibited in the Arpanet from the outset and that
was still the rule as the network changed into the Internet. The network
was an experimental facility supported for research purposes."(Lundh,
18)(20)
IX - Creating an Internet
The protocol suite that makes the Internet possible is known as the TCP/IP
protocol suite (Transmission Control Protocol/Internet Protocol). Lundh
explains the extensive effort needed to transform the design into
functioning protocol specifications. He describes the years of
experiments, analysis of the results, and the design of new experiments to
test the theory developed from the experimental process. Failures or
surprises from the actual experience of the researchers helped them to
make the needed changes in the implementation efforts. Lundh writes:
Those protocols resulted from an extremely thorough analysis and design.
'No stone was left unturned' during the development which took several
years. Theoretical analyses were complemented by experiments.
Combinations of traffic types and requirements, network topologies and
application types were imagined, tried, failed, changed and tried again.
The 'final' TCP and IP were not easily postulated and approved. Nobody
can ever reproduce in a laboratory the chaotic traffic pattern of a
lively telecom or computing network and even less the diverse demands of
information exchange. The growing active dynamic traffic situation in
the ARPANET prevailed during onwards development of its own underlying
technology. That may be one reason for the robustness, elegance and
survivability of the result. (Lundh, 12)
Lundh emphasizes the importance of a functional network with actual users
and traffic as a laboratory for the researchers. He describes how theory
grew out of experimental research and then was used to guide the
experimental process. In this way, the theory was verified or modified.
Recalling his experience, Lundh writes, "During a period of intensively
active development, methods were conceived and perfected until functioning
well in an environment which was closer to reality than anyone might have
dreamt up in a 'sterile' laboratory." This experimental process was
closely intertwined with theoretical development. He adds:
At the same time a profound theoretical understanding was developed. It
kept its scrutiny on experimental results and was both guiding and
following up the work in an admirable teamwork. (Lundh, 12)
Describing the political conditions that had to be accommodated to create
a protocol that would function for the international community, Spilling
explains the rationale of the TCP design:
In order to allow Host computers, connected to different networks to
communicate, these networks have to be interconnected. This is not a
trivial matter, since different networks, in general, are supported by
organizations with different requirements and therefore will develop
differently. Any changes in existing networks in order to interconnect
these, will be costly and impeded by political factors. The obvious
approach therefore, would be to leave the local nets undisturbed and to
perform the interconnections outside them. This is one of the main ideas
behind the TCP. (Spilling, Proposal to Nato, 5)
The protocol requirements were such that the networks participating in the
Internet would not be limited in their internal development or
activities.(21) The use of gateway computers helped in this process.
Gateway computers would reformat the packets of data from the form needed
by one network into the form to meet the requirements of the next network
on their journey to their final destination. The gateway software would
also determine the best next path for the packets of data to take to get
to their destination.
Spilling explains that when Host 1 (on Net 1) wants to exchange data with
Host 2 (on Net 2), it forms the data into Internet packets according to
the TCP format and encloses them in the format required by Net 1. This
action, he says, is called "wrapping." (Spilling, Proposal to Nato, 6)
Spilling attributes the term "wrapping" to an article by Louis Pouzin and
H. Zimmerman. Internet packets are then transported to the gateway where
they are unwrapped from the Net 1 format and rewrapped in the format for
Net 2 for transmission to Host 2 (on Net 2).
X - 1970s Networking Collaboration to Develop Internet Technology
Critical to the scientific process of the development of the TCP protocol
was the international collaboration of researchers working together on its
development. Describing the role of this collaboration, Lundh writes:
(T)he network technology was further refined and developed in an
intimate co-operation of ten research groups during the 1970s. That
co-operation resulted in the technology underlying today's Internet.
(Lundh, 10)
The results were documented and made openly available to anyone around the
world, particularly to academic researchers. The period from 1973 to 1980
was a significant period in the research to develop the Internet. For
Lundh, the Internet is the networking of interconnected nets. "From the
initial ARPANET," he writes, "the technology was developed into a
basically new computer cooperating technology � Internetworking
technology. Its main constituents were defined as proposed standards
around 1980." (Lundh, 10) Further important technical refinements and
geographical expansion occurred in the 1980s.
This development was done on a non-commercial research basis. The earliest
ARPANET development was done on the basis of leased telephone lines. The
research in the mid to late 1970s and into the 1980s, however, included
research on Ethernet, packet radio and packet satellite forms of
communication. Lundh points out that not only was the ARPANET a
laboratory, it was at the same time "an active telecom network, a resource
sharing network and a forum of creative and critical people."(Lundh,
12)(22)
Lundh cites an experiment where three people were located in different
geographical locations, Boston, MA in the U.S., London, England, and
Kjeller, Norway. They held a demonstration conference using speech, which
was observed by other researchers in a meeting at another ARPANET-TIP
international site, at University College London (UCL). Lundh writes:
Each of the three sites... communicated through local area nets
interconnected through gateways via ARPANET and SATNET. The packet
traffic in that Internet situation (new then!) was a combination of that
speech traffic together with 'natural' traffic in the Arpanet at the
time. (Lundh, 13)
Lundh calls this experiment in 1978, "one of the several major milestones
during development of Internet technology." He also emphasizes that not
only did the Internet research result in important and robust standards,
but it also influenced and actually pioneered a new methodology for
developing telecommunication standards. (Lundh, 13)
According to Lundh, ten groups collaborated on developing the TCP/IP
protocols. The whole team, he explains, referred to itself as the "Packet
Switching Protocols Working Group - PSPWG." Eight of the groups were in
the USA, one in England and a small group in Norway. "The development
comprised investigation of a variety of suggested methods. They were
thoroughly studied theoretically and experimentally." (Lundh, 13)(23)
Kirstein adds that in phases of the SATNET research, there were
researchers from Germany and Italy involved and there were also meetings
at their sites.(24)
Communication via e-mail helped the research, along with in-person
meetings held every three months that people from each group attended.
Lundh credits DARPA/IPTO with providing the leadership and much of the
funding for the work. The research, he emphasizes, "had the main purpose
to study and develop resource-sharing networks." (Lundh, 14)
The resources to be shared were the 'power' of the computers, programs and
data of various types. The human users were also seen as a significant
resource. "Further, and not least," writes Lundh, "it was important to
create an environment where human resources could co-operate and
strengthen creativity and knowledge." (Lundh, 14)
Lundh lists ten of the research groups that collaborated on Internet
research in the 1970s. (Lundh, 16)
1. ARPA in Washington, DC, USA; Advanced Research Projects Agency -
Information Processing Techniques Office
2. BBN in Cambridge, MA, USA; Bolt Beranek and Newman
3. SRI in Menlo Park, CA, USA; Stanford Research International
4. UCLA in Los Angeles, CA, USA; University of California
5. ISI in Marina del Rey, CA, USA; Information Sciences Institute
6. Linkabit in San Diego, CA, USA; Linkabit Corporation
7. Comsat in Gaithersburg, Maryland, USA; Comsat Corporation
8. MIT in Cambridge, MA, USA; Massachusetts Institute of Technology
9. UCL in London, England; University College London
10. NDRE in Kjeller, Norway; Norwegian Defence Research Establishment
"The tone was open and could be heated although always friendly. A certain
amount of social occasions usually took place and stimulated the smooth
co-operative spirit. ... The assembled group," Lundh explains,
"constituted a strong and inspiring research team." (Lundh, 17) When not
assembled, "from day to day the researchers exchanged e-mail. It comprised
of discussions, experimental results, comments and programs." (Lundh, 17)
From 1977, the usual 2 day PSPWG was "supplemented," by a third day
"Internet meeting dedicated to techniques for internet-working of
different nets." (Lundh, 17) Also see Appendix.
Following is a list Lundh provides of some of the rotation of meetings.
These were meetings between August 1974 and February 1978. (Lundh, 17):
10-11 Aug 74 On the ferry between Stockholm, Sweden and Abo, Finland
4-5 Sep 75 Linkabit Co, San Diego, California; Host: Irwin Jacobs
12-13 Nov 75 UCL, London, England; Host: Peter Kirstein
12-14 Feb 76 DCA and ARPA, Washington, DC.; Host: Bob Kahn
29-30 Apr 76 BBN, Cambridge, Massachusetts; Host: David Walden
29-30 Jun 76 NDRE, Kjeller, Norway; Host: Yngvar Lundh
23-24 Sep 76 UCLA, Los Angeles, California; Host: Leonard Kleinrock
9-10 Dec 76 UCL, London, England; Host: Peter Kirstein
10-11 Mar 77 Comsat, Washington, DC; Host: Estil Hoversten
8-10 Jun 77 NDRE, Kjeller, Norway; Host: Yngvar Lundh
17-19 Aug 77 Linkabit, San Diego, California; Host: Irwin Jacobs
31 Oct-2 Nov 77 BBN, Cambridge, MA; Host: Bob Bressler
1-3 Feb 78 UCLA, Los Angeles, California; Host: Wesley Chu
Dave Mills, who worked at COMSAT, as chief architect for the Internet from
1977 to �1982, adds that there were several meetings after the ones Lundh
lists, at least until January 1, 1983 when ARPANET computers were
officially to change to the TCP/IP protocol. The actual Internet coming
out party, Mills writes was at the NCC in 1979. (Mills, E-mail, April 28,
2003) The original vision of resource sharing networking was an important
source of inspiration for Internet development. Included in this resource
sharing were technical resources, and even more significantly, the sharing
of human resources, ideas and suggestions. (Lundh, 10)
XI - The Vision
Spilling credits JCR Licklider with the vision that inspired the Internet
developments.
Dr. Licklider, educated both in electrical engineering and psychology,
had the vision of 'an on-line community of people,' where the computers
should help people to communicate and provide support for the human
decision processes.... (Spilling, The Internet)(25)
The vision Licklider proposed was of an "intergalactic network". This was
to be a human computer communications networking utility which would
function like other utilities in that everyone would have access to it.
However, this was to be global and to make it possible for governments,
scientists and people around the world to communicate in a way that was
unprecedented. Licklider's vision was of an on-line community of people.
Computers would help humans to communicate with each other. This vision
inspired the early development of the Internet.(26) It is articulated in
diverse forms through this formative period of the Internet's development.
For example, an editorial in the ARPANET News in February, 1974 explains:
Inherent in the concept of a resource sharing computer network is the
idea of a cooperative, collaborative working mode. This calls for a very
special 'place for people's heads' � a special ability to be cognizant
of and concerned for the welfare of the whole. This long-term objective
and viewpoint requires a personal feeling of responsibility for the
welfare of the network instead of the short-sightedness of acquisitive
self-interest.... With the backing of ARPA-IPT in this endeavor... the
ARPANET shows every promise of becoming the global tool for enhanced
communication and understanding between nations and their scientists and
people that was envisioned for it in its beginning.(27)
The ARPANET News editorial suggests that the ARPANET can be an
international network. The researchers developing this worldwide
networking system, though, recognized the need for something different
from a centralized single network like the ARPANET. Networks like Cyclades
in France, NPL in Great Britain, and the ARPANET in the U.S. were under
the control of different national governments and were developing in
different technical ways suited to the needs of the political and
administrative entities they belonged to. This was the problem posed for
networking researchers of the early 1970s. An international collaboration
made it possible to solve the problem of interconnecting dissimilar packet
switching networks to make communication possible across their boundaries.
Lundh also credits Douglas Engelbart with contributing to the vision of
resource sharing.
While Licklider formulated the vision which inspired networking research,
Lundh points to Kahn's role in providing an overall direction toward
realizing this vision. Lundh writes that "more than anybody else Kahn was
the person who formulated goals and guided development of the Internet
technology during the most active development period." (Lundh, 16)
Kirstein concurs. He writes: "Others had much to do with protocol design
and implementation detail, Kahn had the overall research goals and
direction. He was personally responsible for formulating the programme,
and for ensuring that they followed the right lines. Moreover, when other
activities, like those of the PTTs at the time, threatened some of the
directions of the programme, it was Kahn who formulated activities that
kept the programme on the right lines without alienating the PTTs too
much. Thus when the British Post Office insisted on the use of IPSS (see
earlier), Kahn asked BBN to organise things with relays at BBN in a way
that would allow those channels to be used on the U.S. side � even though
this had no real interest to him in true Internet research." (Kirstein,
E-mail, October 8, 2002)
Kahn had worked on the BBN proposal to design the ARPANET. He was part of
the BBN team to create the IMP subnetwork. He was the author of the
original 1822 protocol specification for the interface between the IMPs
and Hosts for the ARPANET. He also provided important leadership for the
development of the Internet. In an article published in November, 1972,
Kahn presents both human and computer interaction in information
processing as a property of resource sharing networks. He writes:
A principal motive underlying computer network development is to provide
a convenient and economic method for a wide variety of resources to be
shared. Such a network provides more than an increased collection of
hardware and software resources; it affords the capability for computers
as well as individuals to interact in the exchange and processing of
information. (Kahn, "Resource Sharing", 116)
Kahn describes how such networks encourage participation among users. This
is a cooperative process that generates high levels of technical
achievement. He writes:
Computer networks provide a unique mechanism for increased participation
between individuals. Participation in research and development using the
distributed resources of a computer network can lead to close
cooperation between individuals who might otherwise have little
incentive to work together. This interaction can further cross-fertilize
the network community and encourage even higher levels of achievement
through technical cooperation. (Kahn, "Resource Sharing", 117)
In 1972, before the design of the TCP/IP protocol, Kahn proposed that "a
communication system not preclude the possibility that separate... data
networks may be accessed through it if all resources are to be mutually
accessible." (Kahn, "Resource Sharing", 120)(28)
The problem Kahn identified in his article on resource sharing networks is
the need for a means to link the networks of different countries.(29)
Intimately tied to the problem of communicating across the boundaries of
dissimilar packet switching networks, was the need to support a
collaborative process to create a working protocol for an Internet. The
requirements for this protocol were that it be as minimal as possible,
asking only of the differing networks, what was necessary for
internetworking communication. Also it was desirable to have the
internetworking process implemented outside of the individual networks
whenever possible (via gateways, which were later called routers). Then
the networks, themselves, would require the least change, if there were to
be a change in the protocol.
The TCP/IP protocol suite requires the agreement of the participating
networks to certain gateway and operating system specifications in the
host computers. Substantial collaborative scientific research and
experimentation were required to develop the design and work out the
implementation problems. Utilizing the SATNET research, IPTO and their
research community, in collaboration with research groups in Norway and
the U.K., developed and then spread a robust and functional protocol
design and implementation. Subsequently, German and Italian researchers
joined the cooperative efforts. Meanwhile other researchers, particularly
French researchers contributed in important ways. This created the basis
for a global Internet.(30)
In his book The Future of Ideas, Lawrence Lessig advocates preserving the
Internet's unique architecture and culture.(31) He proposes that it is the
end-to-end principle of networking architecture and shared code that are
critical aspects of the Internet. The end-to-end principle requires that
the network not be changed to accommodate the uses of individual entities.
Instead such uses are to be implemented at the ends of the Internet. This
is an important principle for the development of resource sharing in
packet switching networks. This is not, however, sufficient to make an
Internet a reality. Neither is the sharing of programming code, though
this, too, is desirable for Internet development and a desirable
networking goal. The critical aspect of the Internet's development is the
ability to develop an architecture that asks as little as possible of the
collaborating networks and that treats each network as a peer of the
other, rather than subordinating any network to any other. This
architecture, called by Kahn "open architecture", is the critical
principle of the Internet.(32)
This architecture means that each network wanting to interconnect and to
communicate does not have to ask any other network for permission to join.
This is one characteristic that leads Lessig and others to call the
Internet a "commons". Also Internet standards are freely available to all
interested. Therefore, any network can implement the TCP/IP protocol suite
as part of a host operating system and connect with a gateway to other
networks. This "open architecture" of the Internet facilitates its ability
to spread around the globe. Networks do not have to change their nature or
ownership to become part of the global Internet. The Internet welcomes the
technical and political diversity and provides for communication
accommodating this diversity.(33) Communication among those with
differences is a generative process. It is in the interaction of diverse
ideas that new ideas emerge. (Michael Hauben, "The Net and the Netizen",
in Hauben and Hauben, Netizens)(34)
XII - Conclusion
The earliest development of the Internet and its protocol suite TCP/IP
solved the problem of sharing resources across the boundaries of differing
networks and peoples. This development took place during the 1970s. It
demonstrates the generative capacity of a collaborative environment where
the researchers from different nations are able to work together to create
an ever evolving and developing Internet. This is one of the most
significant developments of the 20th century. Will it be studied and
continued? Lessig and others raise the possibility that it may all be
lost. A precious heritage has been contributed by visionaries like
Licklider and Engelbart, and research pioneers like Kahn and Cerf, Davies
and Kirstein, Lundh and Spilling, and Pouzin and Zimmerman. Many netizens
have participated to create this important advance for modern society.(35)
Its loss would be a great setback to our modern world. A collaborative and
resource sharing environment, similar to the one that nourished the
Internet's earliest development, continues to be needed, if we are to
generate the means for the Internet's ongoing evolution.
---------
Special thanks to Yngvar Lundh, Paal Spilling, Gisle Hannemyr, Peter
Kirstein, Les Earnest, Louis Pouzin, Dag Belsnes, Andrew Hinchley, Robert
Kahn, Dave Mills, Vint Cerf, Horst Claussen, and Hans Vorst for providing
background or documents about this important period of Internet history.
Ole Jacobsen, Patrice Flichy and Klaus Fuchs-Kittowski also provided
helpful material or suggestions on people to contact, as did several
people on mailing lists. Please know the help is appreciated. And thanks
to Jay Hauben and in memoriam to Michael Hauben for the work done that has
set a foundation for the understanding of Internet history. Also I want to
thank Dr. Samuel Moyn for his encouragement, helpful comments and
discussion toward the research for this paper.
------
Notes:
(1) There are several books that document aspects of Internet history, and
others that document related developments that set the foundation for the
Internet. These include Janet Abbate, Inventing the Internet, Cambridge,
1999; Katie Hafner and Matthew Lyon, Where Wizards Stay Up Late, N.Y,
1996; Michael Hauben and Ronda Hauben, Netizens: On the History and Impact
of Usenet and the Internet, Los Alamitos, 1997, John Naughton, A Brief
History of the Future, N.Y., 1999, Arthur Norberg and Judy O'Neill,
Transforming Computer Technology, Baltimore, MD, 1996; Howard Reingold,
Tools for Thought, 1985 and reprinted 2000; Peter Salus, Casting the Net,
Reading, MA, 1995; Lawrence Lessig, The Future of Ideas, New York, 2001.
Vint Cerf observes that a lot has been left out of the current histories,
and "that a lot of mistakes are made - the popular 'histories' being the
worst. Even when principals write, we forget details or get them wrong."
And that one of his biggest complaints is that many books focus mainly on
the development of the ARPANET. (Cerf, E-mail, April 13, 2003)
An example of such confusion, mistaking the development of the ARPANET for
the development of the Internet, is in The Internet Galaxy, where Manuel
Castells writes: "The origins of the Internet are to be found in
ARPANET.... The openness of the ARPANET's architecture allowed the future
Internet to survive its most daunting challenge.... ARPANET's protocols
were based on the diversity of networks." (pg 10, 26) (Oxford University
Press, 2001)
(2) See Michael Hauben, "Social Forces Behind the Development of Usenet"
in Hauben and Hauben, Netizens. Draft version online at
http://www.columbia.edu/~hauben/netbook. Also see Robert Kahn, "The
Introduction of Packet Satellite Communication", PROC NTC, November 1979.
To make communication possible among differ entities, there is a need to
have some common conventions or agreements. In computer networking
technology these are called protocols. Describing the nature of
communication in computer networking, Cerf and Kirstein write:
A fundamental aspect of interprocess communication is that no
communication can take place without some agreed upon conventions. The
communicating processes must share some physical transmission medium
(wire, shared memory, radio spectrum, etc.) and they must use common
conventions or agreed upon translation methods in order to successfully
exchange and interpret the data they wish to communicate. One of the key
elements in any network intercommunication strategy is therefore how the
required commonality is to be obtained. In some cases, it is enough to
translate one protocol into another. In others, protocols can be held in
common among the communicating parties.
(Vinton Cerf and Peter Kirstein "Issues in Packet Network
Interconnection")
Kahn describes the importance of recognizing the potential for resource
sharing in computer networking development:
Computer networks provide a unique mechanism for increased participation
between individuals. Participation in research and development using
the distributed resources of a computer network can lead to close
cooperation between individuals who might otherwise have little
incentive to work together. This interaction can further cross-fertilize
the network community and encourage even higher levels of achievement
through technical cooperation.
(Robert Kahn, "Resource Sharing Computer Communications Networks")
(3) "The ARPA computer communication network, ARPANET ... has been in
operation since 1970. The main part of it operates within the U.S., but it
has two tentacles, one to Hawaii and one to Norway and England."
(Spilling, Research Proposal to NATO, 1)
First Norway was connected to the ARPANET, and then Great Britain. Later
even several Eastern European countries were involved with networking and
knew of the ARPANET. (See IIASA Networking Proceedings, Laxenburg,
Austria, 1975)
(4) Kirstein, commenting on the importance of the development of TCP/IP as
the means to make an Internet possible writes:
Kahn is largely right, in that the ARPANET community in the U.S. did not
address these problems. The Europeans connected to the ARPANET did. As
early as 1974, mechanisms for connecting British and French networks
with the ARPANET were being explored. By 1978, interconnection between
the British Research Network and the ARPANET had one link via SATNET and
one via International Packet Switched Service of the British Telecom and
Telenet. The technology used was not that of the final Internet: the
motivation was there. It was just that the protocol wars had not been
settled.
He also comments, "This is the difference, the other mechanisms explored
internetworking: they did not embrace the IP protocols." (Kirstein,
E-mail, October 3, 2002)
(5) See Ronda Hauben, "Developing the New Field of Computer
Communications"
http://www.columbia.edu/~rh120/other/computer-communications.txt
and Ronda Hauben, "The Birth of the Internet: An Architectural Conception
for Solving the Multiple Network Problem"
http://www.columbia.edu/~rh120/other/birth_internet.txt
Cyclades was the name for the network and the host computers, while
Cigale, for the French word for grasshopper, was the packet switching
subnetwork. In 2003, Louis Pouzin was awarded the Legion of Honor award by
the French government for his networking contributions to the Internet's
development.
Offering a description of the difficult environment that made solving this
problem even more challenging, Kirstein writes:
By 1973, many PTTs were pursuing packet-switched networks which led to
the emergence of X.25 - which was, incidentally embraced by Larry
Roberts then at Telenet. This was meant to be, and actually was, an
Internet. All the protocol structure could have been built on top of it.
Indeed, in the British Coloured Books, embraced by the British research
network, this was done. The technology was packet switched, but the
interconnection was virtual circuit. This made it more difficult to move
to much higher speeds at the time. However many half truths were
prevalent in the '80s to state that X.25 could not exceed 1 Mbps - at a
time that the British research network was operating at 8 Mbps.
(Kirstein, E-mail, October 4, 2002)
(6) French researchers like Pouzin and others working on Cyclades, and
U.S. and other researchers involved with the development of the Internet
participated in a number of meetings where they met and shared their
research. For example, at a relatively early stage in the development of
the research to create Cyclades, the director of the program, Louis Pouzin
remembers a visit by Bob Kahn and Vint Cerf to his project on March 19,
1973. Also during that year, Pouzin lists an INFOTECH workshop and INWG
meeting in London, Feb. 20-23, 1973, and INWG meeting in NYC on June 7-8,
1973. He lists a NATO summer school in Brighton at the Univ of Sussex in
England on Sept 10-14, 1973, and an ACM Data Communications Symposium in
Tampa, Nov. 13-15, 1973. (Pouzin, E-mail, April 28, 2003)
(7) Robert Kahn also explains how there was the need to have access to an
experimental system in order to develop a Satellite packet switching
network. "This is the context in which an experimental program on packet
satellite technology was first raised with the British Post Office,
with... Comsat and subsequently with the Norwegian Telecommunications
Administration and the NDRE." Kahn, "The Introduction of Packet Satellite
Communications", Sec 4.5.2.
Dave Mills describes the important negotiations with INTELSAT that Kahn
managed to achieve to be able to use satellite for the SATNET program.
Mills writes:
I reviewed the common carrier documents for the satellite circuits. Bob
actually accomplished something nobody had done before. The war games
were played with the government telcos of six overseas countries and two
domestic U.S. carriers. None of these guys could function relative to
the others.... What seemed to make it work was the participation of the
military and military research infrastructures of the U.S. (DoD), U.K.
(RSRE) and Norway (NDRE).
I don't know where Germany (DFVLR) or the Italians got their support.
There was considerable friction between the landline, earth station and
satellite providers - they came from very different cultural groups with
rigid expectations for revenue.
Case in point was the INTELSAT tariff for SATNET. SATNET used a single
56-kbps SPADE satellite channel, but eventually seven earth stations
shared the channel. INTELSAT wanted to charge full capacity for each
earth station separately, even though only uplink operated at a time.
Bob managed to negotiate more favorable terms, but then there were the
earth station operators, who wanted their fair share of the loot.
Example: INTELSAT charged the earth station operators about U.S. $.05
per connected minute for the satellite channel itself. You might
remember the cost of a call between the U.S. and U.K. was U.S. $2.40 at
the time. Guess who got the difference? For monthly cost to COMSAT for
the INTELSAT channel of U.S. $2160, COMSAT charged DoD some U.S.
$29,000. But, that included the SIMP depreciation used as the satellite
interface. Similar gouging occurred overseas.
(Mills, E-mail, April 19, 2003)
(8) The Tanum earth station built in 1970-71 made possible international
telecom traffic between Sweden and the rest of the Nordic region.
When Dave Mills joined the research effort in 1976, he explains that the
NORSAR circuit was multiplexed with SDAC seismic data and ARPANET traffic.
The biggest problem he writes, "was the unreliability of the Tanum-Kjeller
microwave link." (Mills, E-mail, April 19, 2003)
It is also helpful to know something about the creation of NORSAR to
understand the collaborative relationship between NDRE and IPTO.
Lundh explains that NORSAR is the Seismic Observatory built in
collaboration with ARPA in South Norway in the mid 1960s. "The initiative
and most of the financing," he reports, "was made by ARPA's Nuclear Test
Detection Office in an effort to build a foundation for (an) international
nuclear test ban and to stop underground nuclear tests...." (Lund, E-mail,
April 18, 2002)
This relationship was actually facilitated by a treaty between the U.S.
and Norwegian governments signed in 1968. The agreement was toward the
construction of a large seismic array and research installation at
Kjeller, Norway, just outside of Oslo. After notes were exchanged between
the American Ambassador to Norway at the time, Margaret Jay Tibbets and
the Norwegian Minister for Foreign Affairs, John Lyng, an agreement was
reached which concerned: "seismological research focused on development of
methods and systems for detection and identification of underground
nuclear explosions." See http://www.norsar.no
The NORSAR (NORwegian Seismic ARay) website describes the conditions of
the treaty: "The agreement specified that the purpose of the installation
was to be seismological research and experimentation primarily in the
field of detection seismology. At the same time the agreement provided
that the facility could be used for independent research at the direction
of the Norwegian government. A framework for funding the construction and
operation of the array facilities was also specified."
"Cooperating agencies were authorized on both sides to conclude
administrative agreements to carry out the details of the agreement. The
cooperating agency for the United States has for more than 25 years been
the Advanced Research Projects Agency, while for Norway the cooperating
agency during construction of the NORSAR large-aperture array was the
Norwegian Defence Research Establishment, while the Royal Norwegian
Council for Scientific and Industrial Research (NTNF)was chosen in 1970 as
cooperating agency for the management of the facility...."
"NORSAR opened in 1969. Data gathered by it was transmitted to a data
center in Virginia, the Seismic Data Analysis Center (SDAC). By 1970/71
the Nordic satellite station in Tanum, Sweden was opened to transmit the
data via satellite. The transmission capacity of the satellite was 2.4
kb/s."
Cerf adds that "The ARPA office in charge of Nuclear Detection was called
the Nuclear Monitoring Research Office. Col David C. Russell worked in
that office before he succeeded Larry Roberts and J.C.R. Licklider as
ARPA/IPTO director. On Russell's retirement from the U.S. Army, Bob Kahn,
who was then deputy director of the office, became office director of
IPTO." (Cerf, E-mail, April 13, 2003)
(9) With regard to funding the UCL research, eventually there was also
"funding from IPTO on ARPANET and then TCP/IP experimentation. The funding
mechanism involved the appropriate foreign security reviews, but was
otherwise like any other funding." (Kahn, E-mail, July 22, 2002)
(10) It is generally believed that the transport of seismic data from
Norway to the U.S. was the reason for the Norwegian connection to the
ARPANET. Lundh explains that this is a misunderstanding. It was interest
in the research that IPTO was doing, not the desire to transport seismic
data more efficiently between the U.S. and Norway, that was the motivating
factor for NDRE to accept the invitation from IPTO to join the Internet
research program.
(11) Lundh reports that his first contact with ARPA was in Fall, 1965 when
he "was invited to Washington and to Billings Montana" on the occasion of
the opening of the seismic array in Montana LSSA (Large Scale Seismic
Array). Lundh's interest was, he explains, in "powerful computing methods,
notably multicomputers." His contacts at ARPA were Harry Sonneman and
Stephen Lukasik and occasionally Bob Frosh. (Lundh, E-mail, April 18,
2002)
(12) Kirstein's paper was "On the Development of Computer and Data
Networks in Europe", Proc. Int. Conf. on Computer Communications,
Washington, 240-244, 1972.
Cerf describes some of those present at the ICCC'72. He lists Donald
Davies from the U.K., National Physical Laboratory, Remi Despres who was
involved with the French Reseau Communication par Paquet (RCP) and later
with X.25 networking, Larry Roberts and Barry Wessler, from IPTO, Gesualdo
LeMoli, an Italian network researcher; Kjell Samuelson from the Swedish
Royal Institute, John Wedlake from British Telecom; Peter Kirstein from
University College London; Louis Pouzin who led the Cyclades/Cigale packet
network research program at the Institute Recherche d'Informatique et
d'Automatique (IRIA, now INRIA, in France). Roger Scantlebury from NPL
with Donald Davies may also have been there and Alex McKenzie from BBN
probably was there. (Cerf, "How the Internet Came to Be")
Cerf writes that the IFWP later became the IFIP 6.1. with the help of Alex
Curran who was the U.S. representative to IFIP Technical Committee 6. Cerf
also credits Keith Uncapher and Dick Tanaka with helping this affiliation
to be carried out. (Cerf, E-mail, April 13, 2003)
(13) Spilling, however, writes, "Yngvar and I disagree a little on this
point. I had the impression that Bob Kahn was looking for a good
demonstration object, sort of on a global scale, to defend all the
spending on developing the technology. The seismic detection facility
NORSAR had to send seismic information across a leased line to the
processing plant in Washington, D.C. And what could be a better
demonstration object, than to convey this information via packet switching
technology from Norway to the U.S. From what I understood, Bob Kahn used
this as an example of the usability of the technology � when NORSAR became
connected � toward his defence funding party."
Lundh responds that:
I believe Paal may well be right in his impression of Bob's motive for
inviting Norway. However, my reason for suggesting that NDRE accept the
invitation to actively collaborate and to actually undertake that
collaboration was my interest in resource sharing networking and its
manifold possibilities. That interest was first inspired by Bob Kahn and
Larry Roberts and the Washington, DC conference and demo in 1972. It was
further strengthened later by all that we learned and experienced during
the following years of collaboration. (Lundh, E-mail, October 15, 2002)
Cerf adds that "The original circuit was 2400 baud so the 9600 baud,
circuit, though shared, was faster for the data transport. Later SATNET
provided 64 kb/s service." (Cerf, E-mail, April 13, 2003)
Kirstein writes that "It (Seismic array technology or test detection-ed)
was ARPA's original reason for placing a TIP there. From the time ARPANET
came on-stream in 1970, ARPA wanted to bring the NORSAR array to SDAC in
Washington over ARPANET. This is what justified the bulk of the ARPA
expenditure (from the Nuclear Monitoring Research Office - NMROP on the
link in the early days.) I do not know when the extension ... which did
result from the extended IPTO interest in the NMRO activity, put actual
expenditure in the IPTO budget." (Kirstein, E-mail, October 8, 2002)
(14) Important developments in satellite technology in the 1960s and early
1970s led to the development of INTELSAT IV and made possible the SATNET
packet switching network. Abramson and Kuo write:
In 1970 the ARPA Network came into existence as a communications network
for the sharing of resources among a large number of computer centers.
The ARPANET and its resource sharing capabilities became feasible
because of the use of a new method of communication system organization
� called packet switching.... In April 1965, the scope and nature of
human communication was irreversibly altered by the successful launch of
INTELSAT I, the first geosynchronous communication satellite. Since that
time the cost of information transmission over long distances has
decreased at a rate that makes even the present decrease in information
processing costs seem mild by comparison. The cost per year of a single
voice grade channel in INTELSAT I was about $20,000 per year; that
satellite had a capacity of 24 such channels. The corresponding cost on
INTELSAT IV, launched in January 1971 was about $2,000 per year, and
each INTELSAT IV has about 5,000 channels....
By the beginning of 1973 the lower cost, higher channel capacity, higher
power, and small ground stations required by new communication
satellites had suggested the magnitude of the impact these developments
would make in computer-communication networks of the future.... By the
end of 1972, the worldwide satellite communication net of INTELSAT had
been completed.... (from Preface, Norman Abramson and Franklin F. Kuo,
Computer-Communications Networks edited by Abramson and Kuo, 1973,
Englewood Cliffs, N.Y., xvii.)
(15) For further elaboration see Ronda Hauben, "The Birth of the Internet"
http://www.columbia.edu/~rh120/other/birth_internet.txt and Ronda Hauben,
"Open Architecture", in The Encyclopedia of Computers and Computer
History. Raul Rojas, Editor, Fitzroy Dearborn, Chicago, 2001, vol 2, pp.
652-653.
Kirstein adds:
This was Kahn's thinking, but there was also a practical consideration.
The basis of all the network itself between 1969 and 1974 was the IMP,
and this was firmly under the control of one division of BBN. With the
interest in the Packet Radio and SATNET, any attempt to connect them was
delayed by the need to further develop the IMP to meet all its demands.
This was one very important reason why Kahn proposed a �gateway' which
could be programmed by others, freeing the programs from the
stranglehold of one group. In practice the IMPs could now be developed
differently for the different network technologies. Moreover, an
important development occurred. Shortly after, in 1975/76 when Dave
Mills (then at COMSAT) programmed the �fuzzballs', to provide a cheaper
and more lightweight alternative to the BBN implementation. (Kirstein,
E-mail, July 3, 2002)
Cerf elaborates,
In this case, the fuzzballs were functioning as routers - handled IP
switching as opposed to the IMPs. The apples-to-apples comparison would
be between fuzzballs and the BBN Internet Gateways. I believe in fact
the fuzzballs were providing all the functionality of the IMPs and the
gateways by switching IP packets. (Cerf, E-mail, April 13, 2003)
Kirstein adds that the development of the application level relay "during
this period was also a new form of interconnection" which "allowed all the
British network developments to occur independently of the U.S. ones, but
traffic still to flow easily between the networks."
He explains that,
This was not an interconnection at the network level, but at the
application protocol level (Telnet, FTP initially). This form of
interconnection was new at the time, (and-ed) allowed the different
networks to develop quite independently. In fact it was to exercise this
new concept, that all the traffic between the U.K. and ARPANET was
justified in the '70s and early '80s. Later in the '80s, this concept
even allowed the U.S. to develop Mockapetris' Domain Name System, while
the U.K. developed the 'Network Registration Service'.
"While these developments were quite different," Kirstein notes that, "the
relay function allowed them to look to users as a single network....
Clearly application level relays are not adequate in performance or
robustness, however, they played an important role prior to the world
agreeing that IP was the way to go." (See the article by V.G. Cerf and
P.T. Kirstein, "Issues in Packet Network Interconnection," Proc IEEE 66,
11, pp 1386-1408, November 1978. This is a special issue devoted to packet
internetworking issues.)
Kirstein adds:
In fact the original grant I had from ARPA was to connect in two
computers, the large IBM Computer at the Rutherford Laboratory near
Oxford and the CDC in London. Both were the centre of centralised
proprietary interactive and remote job entry networks. This connection
was made as one between two networks from the beginning. It looked to
ARPANET as if IBM was directly connected as a Host, and any ARPANET Host
looked like a remote IBM device. (Higginson, PL, PT Kirstein and AV
Stokes: "The Problems Connecting Hosts into ARPANET via Front-end
Computers", Workshop on Distributed Computer Systems, Darmstadt (1974).
Lloyd, D and PT Kirstein: "Alternative Approaches to the Interconnection
of Computer Networks", London, Proc European Comp. Conf. on
Communications Networks, London, Online, 499-515 (1975))
Kirstein continues:
This was not an Internet design; this was connections at an application
level, and hence not very rugged. However, this mechanism continued for
the next 15 years, while the British NREN became quite sophisticated,
including packet switching, their version of the Domain Name Service
(Name Registration Scheme), FTP, Telnet, mail, etc. By 1990, while the
links to the Internet had long gone IP, the hosts on the British
networks were running a totally different set of protocols. While
history (and the analysis we made at the time) showed this was not the
best, rugged or fast way to go, it allowed both interconnectivity and
independent development of protocol structures to co-exist until all the
bugs had been resolved in the Internet protocols, and also commercial
products to be produced by new firms such as Cisco.
(Kirstein, E-mail, Oct 3, 2002)
(16) The Brighton INWG meeting took place just after the NATO Advanced
Institute. Though the original protocol was called TCP, it later was split
into two parts and from then on called TCP/IP. When the paper describing
the philosophy and design for TCP was officially published in May, 1974,
the authors, Vint Cerf and Bob Kahn, wrote: "The authors wish to thank a
number of colleagues for helpful comments during early discussions of
international network protocols especially R. Metcalfe, R. Scantlebury, D.
Walden, H. Zimmerman. D. Davies and L. Pouzin who constructively commented
on the fragmentation and accounting issues, and S. Crocker who commented
on the creative destruction of associations."(p 643) (See also, Ronda
Hauben, "A Protocol for Packet Network Intercommunication", in The
Encyclopedia of Computers and Computer History. Raul Rojas, Editor,
Fitzroy Dearborn, Chicago, 2001, vol 2, pp. 652-653.)
(16a)Describing the process of creating a protocol specification, or
Request for Comment (RFC), Mills writes, "One of the principal drivers in
the standardization effort was the published TCP and IP standards, which
were issues both as RFCs and Military Specifications (MILSPEC). Bob
considered this a major coup. Later, DoD policy saluted COTS (Commercial
Off the Shelf) and told the agencies to avoid MILSPEC. Nobody at the time
happened to notice that TCP and IP were MILSPECs.
There is a lot more to the formal specification issues. The RFCs were
designed principally as instructions to system programmers on how to
implement the protocol and as such should not be considered formal
standard specifications. Later at great expense and contractor involvement
(SDC) a formal specification was in fact prepared. I was consultant on
that project, which did in fact do the right thing. So far as I know, the
document is rusting in a dark place." (Mills, E-mail, April 28, 2003)
(17) Remembering the meeting in Brighton, U.K. in September 1973, Lundh
writes that he first met Dag Belsnes at it. Lundh writes that "it was
clear to me then that Dag knew much more than I did about protocol
details."
Describing his introduction to networking research, Belsnes writes that he
had "started working with data communication in 1970 at the University of
Oslo. The university was (connected) by a CDC Cyber computer together with
some other research institutions (among them, the Norwegian Defense
Research Establishment, where Yngvar was working) and the computer was to
be located about 25 km away from the university campus. I headed a team,"
he writes, "that implemented a network system to connect this remote
(system-ed) at the university (a CDC 3300, Nord computer (a mini-computer
of the Norwegian company Norsk Data) and later a DEC 10.) The design of
the local university network was highly influenced by what we could read
about ARPA and Cyclades networks." (Belsnes, E-mail, June 17, 2002)
Explaining Belsnes' contribution, Cerf writes: "Actually Dag worked out
the need for a 5-way handshake to assure that old duplicate packets would
not be confused for new ones. We concluded this was too much overhead and
chose a three way handshake with a timeout mechanism to 'clear the net' of
old packets from a given connection. I considered Dag's work to provide a
very solid ground for the TCP - as did Ray Tomlinson, Yogen Dalal who
worked on the 3-way version and Carl Sunshine who did correctness proofs
for this version." (Cerf, E-mail, April 13, 2003) Also Kuninobu Tanno
(from Tohoku University) from Japan was part of the Stanford seminars Cerf
held to explore "how to get host computers to communicate across multiple
packet networks without knowing the network technology underneath." (Cerf,
"How the Internet Came to Be")
(18) See the diagram from the "Uses of the ARPA Network via the University
College London Node" by Peter T Kirstein and Sylvia B. Kenny, IIASA
Conference on Networks, Laxenburg, Austria, 1975, p. 54. Lundh calls
Kjeller "the little townlet where some research establishments reside,
some 20 km NE of OSLO."
Cerf explains that the TIPs were just part of the ARPANET, "we did not yet
have gateways/routers running IP." (Cerf, E-mail, April 13, 2003)
(19) Lundh also writes:
Later, I believe, around 1981-82 when I could no longer get even the
small support needed at NDRE, Paal left NDRE (with my blessings) and
took the equipment with him to the neighboring institute (�TF'), the
research establishment of the Norwegian Telecom Administration. They are
located at Kjeller also, just across the street from NDRE and next to
NORSAR. Paal was alone there being interested in Internetworking. NTA
did not believe in the Internet until about 1995 � similarly to most
telecom operators.... I think only one person at TF gave Paal some help
during those years. Going back some years again, a few months after Paal
joined me he also got another friend of his (Aage Stensby) over from his
old group at NDRE, having become 'similarly superfluous' there. However,
Paal was the main contributor without any doubt. Later on I was able to
recruit a few more people to the networking effort.... The most active
ones were Oyvind Hvinden and Finn Arve Aagesen. Both (were) very good
people.... Finn Arve is an unusually able person and made a great
contribution during the short time he was with us....
(Lundh, E-mail, June 12, 2002)
(20) Kirstein disagrees about the prohibition of commercial sites, though
not of commercial traffic. He writes that the UCL connection was to the
public telecom and consequently was accessible to both commercial and
academic sites. There was broad usage of the network in the U.K. and hence
there was much interest in it. As Kirstein explains, "A management
committee, which included the British Post Office, had to approve all
sites connected and their use. From the late '70s, applications included
quasi-commercial usage where one site was a British contractor to a U.S.
Agency, and the other the U.S. Agency or another such U.S. contractor �
usually in relation to R & D projects. When requested by the U.S. such
usage was normally approved; we were only concerned that the experimental
nature of the interconnection would not lead to any legal responsibilities
to the user entities. In the U.K. we connected the TIP to the Public
Telephone network immediately (by September 1973, and to the British
research networks (from late 1973))." (Kirstein, E-mail, October 8, 2002.)
"I should add," he writes, that "the British Post Office was part of the
management committee which was told all that we were doing. For this
reason they tolerated activities they might otherwise have forbidden; they
were clearly contrary to their monopoly." (Kirstein, E-mail, Oct. 3, 2002)
(21) Spilling continues: "The control program therefore must be an
integral part of the programs in the Host computers wishing to participate
in internetwork connections. The device interconnecting the two networks
is called a Gateway.... The Gateway is connected to the two networks. Net
1 and Net 2, in the same way as normal Host computers, and therefore looks
like a Host to both networks. When Host 1 wishes to exchange data with
Host 2, it forms an internet packet according to the TCP format and
encloses it in the format required by Net 1, for communications in that
network. This action ... is called 'wrapping.' The internet packet is then
transported to the Gateway where it is unwrapped from the Net 1 format and
is re-wrapped in the format for Net 2 for transmission across the net to
Host 2. This process can easily be extended through an arbitrary number of
networks and gateways. This form of data exchange between Host 1 and Host
2 looks to all intermediate networks like normal host-host communications,
thus the local networks are not aware of any internetwork activities. This
is taken care of by the TCP's in Host 1 and Host 2 and by the Gateway."
(Spilling, Proposal to NATO, pg 5)
Cerf explains the process using the term "encapsulation":
We adopted very early the idea of encapsulating IP packets in the
packets of connected networks - the gateways would remove the IP packets
from the carrying packet format and re-encapsulated it in the next
networks packet structure. Of course, before we split IP from TCP, it
was just TCP packets that were encapsulated.
(Cerf, E-mail, April 13, 2003)
(22) See Spilling, "Final Report," for a description of how the SATNET
program was initially developed using the ARPANET and gradually separated
apart from the ARPANET. The SIMPs were the Satellite IMPs created for
interfaces for SATNET. He writes: "The purpose of the Packet Satellite
Program is to develop a general-purpose satellite network based upon the
packet-switching principles... In order to utilize as much as possible the
facilities available in ARPANET, the initial satellite network was an
integral part of ARPANET.... During the program period, the SIMPs were
developed to a stage where they could be separated from the ARPANET, so
that the SIMP programs could be optimised for the satellite
environment.... As mentioned, the SIMPs initially were logically a part of
ARPANET and therefore had to obey the ARPANET IMP-IMP protocol. This was
done in order to utilize the ARPANET techniques in maintaining and
controlling the satellite part of the network from the Network Control
Center (NCC) at BBN. Gradually the SIMP programs were evolved to such a
level that SATNET could be separated from ARPANET, and its operation fine
tuned to the satellite environment. The separation made it necessary to
develop an interface both for host access to SATNET and for access to and
from other nets...."
(23) See list of the PSPWG notes in Spilling, "Final Report".
(24) Kirstein writes, "Certainly by 1979, the SATNET project as a
development project had been largely completed. There was a major meeting
in Washington, with a session on SATNET. I know that UCL participated in
it.... At that meeting we used packet voice to present part of the
proceedings from London in Washington. I am sure that CNUCE (Pisa, Italy)
and DFVLR (Munich, Germany) were well and truly aboard by them. Equally
clearly the SATNET route had become an operational entity by around 1983,
using TCP/IP. Shortly after that the academic parties in Italy and Germany
dropped out. The Defence parts never played any important role in network
development in Germany, Italy or the U.K." See also Kirstein, PT, et al.
"SATNET Applications Activities", Proc. Nat. Telecom. Conf. Washington,
45.1.1-45.1.7(1979). (Kirstein, E-mail, October 3, 2002)
Cerf adds that "In fact, we formed a coordination board - the
International Coordination Board (ICB) that included NDRE, UCL, the German
DFVLR and the Italian CNUCE as well as DARPA to coordinate the
international efforts." (Cerf, E-mail, April 13, 2003)
(25) In "The Internet- A Cuckoo in the Telecom Service Nest An Evolution
in Packet Switching" Spilling gives as an example of such a decision
process � the command and control processes of the Department of Defense.
(26) See Michael Hauben, "The Vision of Interactive Computing and the
Future" and Ronda Hauben, "The Birth and Development of the ARPANET" in
Netizens and Ronda Hauben, "Licklider" in Encyclopedia of Computers and
Computer History. Often, in funding proposals, it seems that only computer
resource sharing is referred to rather than human communication
facilitated by computers. See for example Ronda Hauben, Chapter 1, in
Cyberhypes(in German).
(27) ARPANET News, February 1974, Editorial, pp. 2-3.
(28) These statements of a vision for a communications system identified a
goal for the development process and thus made it possible to evaluate
whether the actual development makes progress toward this goal or not.
(29) Several articles provide an overview to document this international
collaborative research process. Such a process, was essential to develop
both a prototype and then the Internet. See for example: Kahn, Robert E.,
"The Introduction of Packet Satellite Communications," in Proc NTC,
November, 1979, pp. 45.1.1-45.1.6.
Lundh, Yngvar, "Yngvar Lundh: Computers and Communication � Early
development of Computing and Internet Technology - a Groundbreaking part
of Technical History". in Telektronikk Vol 97 No 2/3 2001, pp. 3-19.
Paal Spilling, "Research Proposal presented to NATO, Scientific Affairs
Division by Norwegian Defence Research Establishment also on behalf of
University College London and Stanford University, California concerning
A Study of the Transmission Control Program, a Novel Program for
Internetwork Computer Communications" 2 December 1975, NDRE.
(30) Also the packet radio network (PRNET) program made important
contributions to the creation of the Internet. See Kahn, Robert E., "The
Organization of Computer Resources into a Packet Radio Network", IEEE
Transactions on Communications, Vol Com-25, No. 1, January 1977, pp.
169-178.
(31) Lessig writes,
The environment of the Internet is now changing. Features of the
architecture � both legal and technical that created this environment of
free creativity are now being changed. They are being changed in ways
that will reintroduce the very barriers that the Internet originally
removed. (Lessig, p. 16)
(32) Considering the international collaborative process needed to develop
"open architecture" as the foundation for the Internet, it is interesting
that Lessig describes architecture as referring "to both the Internet's
technical protocols (e.g. TCP/IP) and its entrenched structures of
governance and social patterns of usage that themselves are not easily
changeable, at least not without coordinated action by many parties."
(from Lawrence Lessig and Paul Resnick, "Zoning Internet Speech," Michigan
Law Review, 98 (1999):395, quoted as footnote 34 in Lawrence Lessig, The
Future of Ideas, Random House, NY, 2001, p 276.)
(33) See Kirstein and Cerf's explanation of the conventions needed to make
communication possible in their November 1978 article.
(34) Describing the work of Licklider and Taylor in their article "The
Computer as a Communication Device", Michael Hauben writes:
Their concept of the sharing of both computing and human resources
together matches the modern Net. The networking of various human
connections quickly forms, changes its goals, disbands and reforms into
new collaborations. The fluidity of such group dynamics leads to a
quickening of the creation of new ideas. Groups can form to discuss an
idea, focus in or broaden out and reform to fit the new ideas that have
been worked out. (from "The Net and Netizens: The Impact the Net has on
People's Lives", Chapter 1 in Netizens)
(35) Michael Hauben, "Preface", Netizens.
------------
Bibliography
ARPANET News, October 1973.
ARPANET News, February 1974. Issue 12 NIC 21646,
http://198.92.252.3/arpanet/
Cerf, Vinton, "Final Report of the Stanford University TCP Project," IEN
151, 1 April 1980.
Cerf, Vinton, "How the Internet Came to Be: as told to Bernard Aboba," in
The Online User's Encyclopedia by Bernard Aboba, Addison-Wesley, November
1993.
Cerf, V.G. and P.T. Kirstein, "Issues in Packet Network Interconnection,"
Proc IEEE, 66, 11, pp 1386-1408, November 1978.
Cerf, V., "Packet Satellite Technology Reference Sources," RFC892,
November, 1982.
Cerf, V. and R. Kahn, "Towards Protocols for Internetwork Communication,"
IFIP/TC6.1, NIC 18764, INWG 39, Sept 13, 1973.
Cerf, V. and R. Kahn, "A Protocol for Packet Network Intercommunication",
IEEE Transactions on Communications, vol com-22, No. 5, May 1974.
Davies Donald W., "Early Thoughts on Computer Communications", n.d.
Hannemyr, Gisle (1999) Begynnelsen p� en historie om Internett; I
Nettsamfunn, (red., Braa Hetland og Liest�l) Tano-Aschehoug, Oslo, 1999,
pp. 11-27.
Hauben, Michael, "The Social Forces Behind the Development of Usenet," in
Netizens.
Hauben, Michael, "The Vision of Interactive Computing and the Future," in
Netizens.
Hauben, Michael and Ronda Hauben, Netizens: On the History and Impact of
Usenet and the Internet, IEEE Computer Society Press, Los Alamitos, 1997.
Hauben, Ronda. "The Birth of the Internet: An Architectural Conception for
Solving the Multiple Network Problem."
http://www.columbia.edu/~rh120/other/birth_internet.txt
Hauben, Ronda, "Developing the New Field of Computer Communications"
http://www.columbia.edu/~rh120/other/computer-communications.txt
Hauben, Ronda, "Licklider", in The Encyclopedia of Computers and Computer
History. Raul Rojas, Editor, Fitzroy Dearborn, Chicago, 2001, vol 1, pp.
465-466.
Hauben, Ronda, "Open Architecture", in The Encyclopedia of Computers and
Computer History. Raul Rojas, Editor, Fitzroy Dearborn, Chicago, 2001, vol
2, pp. 951-952.
Hauben, Ronda, "A Protocol for Packet Network Intercommunication", in The
Encyclopedia of Computers and Computer History. Raul Rojas, Editor,
Fitzroy Dearborn, Chicago, 2001, vol 2, pp. 652-653.
Hauben, Ronda, "Die Entstehung des Internet und die Rolle der Regierung'"
in Cyberhypes: Moglichkeiten und Grenzen des Internet, Rudolf Maresch and
Florien Rotzer, editors, Suhrkamf, Frankfurt am Main, 2001, pp. 27-52.
IIASA, Workshop on Data Communications, International Institute for
Applied Systems Analysis, Laxenburg, Austria, September 15-19, 1975
Kahn, Robert E., "Resource-Sharing Computer Communications Networks," in
Proceedings of the IEEE, November, 1972, pp. 1397-1407.
Kahn, Robert E., "The Organization of Computer Resources into a Packet
Radio Network", IEEE Transactions on Communications, Vol Com-25, No. 1,
January 1977, pp. 169-178.
Kahn, Robert E., Steven A Gronemeyer, Jerry Burchfiel, Ronald C.
Kunzelman, "Advances in Packet Radio Technology," Proceedings of the IEEE,
Vol 26, no. 11, November 1978, p. 1468.
Kahn, Robert E., "The Introduction of Packet Satellite Communications," in
Proc NTC, November, 1979, pp. 45.1.1-45.1.6.
Kahn, Robert E., Babbage Institute Interview (Arthur Norberg) 22 March
1989.
Kahn, Robert E., Babbage Institute Interview (Judy E. O'Neill), April
1990.
Kahn, Robert E., Vinton G. Cerf, "What Is The Internet (And What Makes It
Work)", http://www.internetpolicy.org/briefing/12_99_story.html
Kirstein, Peter, "Early Experiences with the ARPANET and INTERNET in the
U.K." (http://www.computer.org/annals/an1999/a1038abs.htm)
Kirstein, Peter and Sylvia B. Kenny, "The Uses of the ARPANET via the
University College London Node," in IIASA Workshop on Data Communications,
Laxenburg, Austria, 1975, pp. 53-62.
Kirstein, Peter, E-mail, July 3, 2002 E-mail, October 4, 2002
Leiner, Barry, "Globalization of the Internet", in Internet System
Handbook, ed, Dan Lynch and Marshall Rose, Reading, MA: Addison Wesley,
1993.
Leiner, Barry, et al, "A Brief History of the Internet", Feb 20, 1998,
http://www.isoc.org/internet/history/brief.html.
Lessig, Lawrence, The Future of Ideas: The Fate of the Commons in a
Connected World, Random House, New York, 2001.
Licklider, J.C.R. and Robert Taylor, "The Computer as a Communication
Device," in Science and Technology: For the Technical Men in Management.
No 76. April, 1968, pp 21-31. Also reprinted in In Memoriam: J.C.R.
Licklider: 1915-1990, Report 61, Systems Research Center, Digital
Equipment Corporation, Palo Alto, California, August 7, 1990, pp. 21-41.
Lundh, Yngvar, "Yngvar Lundh: Computers and Communication - Early
development of Computing and Internet Technology - a Groundbreaking part
of Technical History". in Telektronikk Vol 97 No 2/3 2001, pp. 3-19.
Lundh, Yngvar, E-mail April 9, 2002 E-mail April 18, 2002 E-mail April 26,
2002
Mills, Dave, E-mail, April 19, 2003
NORSAR web site - http://www.norsar.no/
Pouzin, L., editor, The Cyclades Computer Network, North-Holland,
Amsterdam, 1982.
Pouzin, Louis, E-mail, April 28, 2003
Rosenzweig, Roy, "Review Essay: Wizards, Bureaucrats, Warriors and
Hackers: Writing the History of the Internet", American Historical Review,
December, 1998.
Spilling, Paal, "The Internet - A Cuckoo in the Telecom Service Nest An
Evolution in packet switching services," in ..... Spilling, P., "The
Internet - An Evolution in Packet Switching", INDC'96 Conference, June
1996, Trondheim, Norway.
Spilling, P., Lundh Y, Aagensen F.A., "Final Report on the Packet
Satellite Program", Intern Rapport, E-290, FFIE, December, 1978.
Spilling, Paal, "Research Proposal presented to NATO, Scientific Affairs
Division by Norwegian Defence Research Establishment also on behalf of
University College London and Stanford University, California concerning A
Study of the Transmission Control Program, a Novel Program for
Internetwork Computer Communications." 2 December 1975, NDRE.
Winkler, Stanley, editor, Computer Communication: Impacts and
Implications, the First International Conference on Computer
Communication, October 24-26, 1972, Washington, D.C.
----------------------
Appendix
Additional Comments from the Researchers
An issue of the Computer Communications Review (vol 20, no 5, Oct 1990)
provides a set of ARPANET maps documenting different phases in the
development of the ARPANET. The maps are also helpful in providing a
chronology of the transition from the ARPANET to the Internet.
Following are some of the relevant dates:
Jun. '75 - Satellite circuits now cross oceans to Hawaii and the U.K.
First TCP implementations tested in this configuration by Stanford, Bolt
Beranek and Newman (BBN), and University College London (UCL).
April '79 - Multiple satellite links to U.K. and Norway. According to
Kirstein, one U.K.-U.S. link made via the commercial British Post Office
International Packet Switched Service(IPSS) using IP/X.25, the other using
the SATNET. Some U.K. traffic starts using the IPSS route.
Mar '82 - Norway leaves the ARPANET and become an Internet connection via
TCP/IP over SATNET.
Nov '82 - UCL leaves the ARPANET and becomes an Internet connection.
Cerf writes that in 1979 satellite systems were extended to include the
ground stations in Italy and Germany. (Cerf, "How the Internet Came to
Be") Horst Claussen confirms this:
Describing the participation of Germany in SATNET, Claussen writes:
Having no access to some of the documents I saved back in Salzburg: the
first access to the ARPAnet was established in the 1977-1978 time frame
when I was involved in the DARPA HOL program which later on led to the
programming language Ada. We connected through a Public Data Network to
the VAN gateway at BBN and were �on the net'. Later on the idea came up
to cooperate with the German Space Research Center (then DFVLR - now
called DLR) in Oberpfaffenhofen who was involved in satellite
communications and had a cooperation with Comsat Labs. Comsat Labs also
was involved in the SATNET and this way we got back to DARPA - Bob Kahn
was very supportive and so was Vint Cerf. Then I joined DFVLR in 1981
and we found support in the German Ministry of Defense and we also could
get funding for a PSP (I recall that the thing cost U.S. $275K - and
that at a time when the exchange rate for the German Mark fell through
the bottom!) The most difficult thing was to get the support of the
German PTT - Research Center people who �owned' and operated the ol
Symphoni Station a Raisting; Symphonie was an early satellite project
funded by the EEC which had been terminated and there was this beautiful
antenna and ground station building sitting empty at Raisting. Mostly
through the unofficial support by the local engineers we were able to
set up the PSP and the gateway at Raisting and connect to the research
center at Oberpfaffenhofen which is some 20 miles away. Don't ask me how
much we had to pay for the 9.6 kbit/sec leased line from
Oberpfaffenhofen to Raisting - horribly expensive.
When it comes to the exact dates I will have to dig up some of my old
files but officially it must have been at least 1982, maybe even 1983
until we got the official permission, however, we did operate the SATNET
station almost a year under a �temporary testing agreement'.
In May 1985 we ran a combined Packet Radio - SATNET demonstration for
the German Armed Forces and for the U.S. Army at Heidelberg
simultaneously and this was quite successful. SATNET was in operation
after I left DFVLR for another year or two and used mainly for
measurements and tests besides being used for Internet protocol
development. (I forgot to mention that we did implement IP, TCP, UDP
etc. in Modula-2 for our own VAX system and that this implementation was
later ported to the Siemens computers used by FGAN (another government
lab working for MOD) for the Packet Radio - SATNET demonstrations.
(Horst Claussen, E-mail, April 17, 2003)
Hans Dodel offers a similar account:
The German participation in SATNET began in the seventies, when the
German military became interested enough to ask their �Consultant
Agency' IABG to watch what was going on there. Within IABG it was Dr.
Horst Claussen who would come to the SATNET meetings then, which I
joined in 1979 or 1980.
Horst and I both joined the German Air and Space Administration DFVLR
and spent many years there, working on SATNET and establishing the first
Gateway to SATNET in continental Europe. (I think the Royal Signals and
Radar Establishment in Malvern, U.K., beat us by a few months.)
(Hans Dodel, E-mail, April 17, 2003)
These accounts help to document that there were both ARPANET and Internet
connections between UCL, Norway, Germany and the U.S. The Packet Satellite
Program (PSP) provides a means of understanding the transition from the
ARPANET to the Internet with the development of TCP/IP. First the ARPANET
was used to develop TCP/IP. Then SATNET was created as a packet satellite
network, and the research on TCP/IP was transitioned from the ARPANET to
SATNET providing communication between diverse networks via TCP/IP. Hence
this was an important step to creating the Internet. A series of Packet
Satellite Program Working Papers (PSPWP) were issued to document "Ideas,
specific investigations, and results and software and hardware
specifications." (Spilling, Lundh, and Aagesen) Like the Packet Switching
Protocol group that Lundh describes, the Packet Satellite Program (PSP)
held regularly scheduled meetings, rotating through the institutions where
the researchers worked. This was to encourage the exchange of ideas and
the coordination of their activities. Norwegian researchers explain the
nature of the program. They write (Spilling, Lundh, and Aagesen):
In mid 1975 the Packet Satellite Program (PSP) was initiated by DARPA,
with the purpose to develop a satellite-based, packet-switching
communication network, to demonstrate its capabilities, and to
investigate its performance factors.
The program involved the collaboration of a number of research groups in
the U.S. and Europe. In the appendix to the Report they list the groups.
SATNET was used as an experimental testbed for their research. To begin
with, SATNET was an integral part of the ARPANET, but as the research
evolved, SATNET became a free standing separate network. The devices
connecting SATNET with the ARPANET were called Gateways.
Describing the importance of gateways and Kahn's foresight regarding the
development of the Internet, Kirstein writes:
Bob Kahn's real contribution here was to recognize in 1974 the
conceptual need of these gateways and to design them at a level which
would endure. (Kirstein, E-mail, July 3, 2002)
Kirstein also describes other important innovations that were crucial at
the time, but didn't endure. Yet these innovations played an important
role in helping the Internet survive a number of obstacles it faced.
Kirstein writes, (Ibid):
One of the really important developments of the mid '70s was the ability
to create relays and gateways between networks to allow different
technologies to be interconnected � without a complete capitulation by
each group to adopt the U.S. and Internet Suite. Some like DECNET and
BITNET capitulated in the late '80s; others like the British networks,
stayed different until the early '90s. However, it was because they were
interconnected, and IP was then demonstrated to be better that it really
won the war.... My own approach was pragmatic; it worked well at the
level, and for the purpose, that I intended; however, it could not be
extended to meet the needs of the future generation. To give ... an
example of the importance of the connection capability, I was ordered by
1977 (by people in our research council) to stop work on IP networks,
because they were contrary to the British activities. It was only
because of support from other bodies in the U.K. and U.S., and because I
could continue to work with the IP networks connected to the favoured
British flavours, that the large-scale experimental services could
continue over the next 10-12 years.
Elaborating on how ARPANET and SATNET were different entities, Spilling
writes:
ARPANET and SATNET operated in parallel for a long period. UCL in
London and NDRE at Kjeller had both access to ARPANET via a TIP at UCL
and a TIP at Kjeller.... There was a leased line from London to Kjeller
and a fully or partly defence-related line from Kjeller to Wiesbaden in
Germany and then over satellite to the ARPANET in the U.S. This was the
situation as far as I can remember until say mid 1982. The SATNET
experiment ran from 1976 till 1979. Then it turned �operational.' That
meant, no real experiments. Further it meant that European sites, mainly
NDRE and UCL could start interconnecting their local networks to SATNET
via Gateways at Kjeller and UCL, and communicate with U.S. hosts through
a Gateway in the U.S. This replaced gradually the services provided by
the TIPs or via the TIPs. This was then to be known as the INTERNET,
with capital letters, and as such was a fact at the end of 1979.
Spilling notes that:
ARPANET links from the U.S. over satellite to Kjeller and a narrow-bank
link further on to UCL, were not efficient and required special
treatment by BBN. It was therefore a push to move away from ARPANET and
over on SATNET. NDRE had its first INTERNET host up 1981/82, making use
of Dave Mills' 'fuzzball' software.
But Spilling does not have a direct reference to when the ARPANET link to
Kjeller/London was decommissioned. Kahn confirms these accounts. Kirstein
remembers that it was in 1981 that UCL used SATNET. He writes,
UCL was the first to introduce the Internet protocols as their sole way
of communicating with the ARPANET in 1981. This was not to be
pioneering. We changed computers and the new ones did not support NCP.
(Kirstein, E-mail, October 3, 2002.)
Spilling writes (Kahn, E-mail, Sept. 5, 2002):
(I)n the 1970s, I initiated a broadcast packet satellite (SATNET)
experiment on INTELSAT IV with the first participants being the U.S. and
U.K. The third participant (of what eventually were five participants)
was Norway. We were already conducting internet experiments over SATNET
in the late 1970s using TCP/IP.
In the early 1980s, we decided to rely solely on SATNET for connectivity
with Europe and thus the two 9.6 kbps lines, which were running in
parallel with the SATNET connections, were decommissioned.
As Kirstein and Kahn emphasize, there were five nations who were
participants in the SATNET experiment. He writes that SATNET included not
only the U.S., Norway and Great Britain, but eventually also sites at
DFVLR in Oberpfaffinghofen, Germany (near Munich), and CNUCE in Pisa,
attached to the Fucino earth station in Italy. (Kirstein, E-mail, July 3,
2002) Providing a general chronology of the development of the 3 different
packet networks that TCP/IP interconnected to become the Internet,
Spilling writes, "DARPA ... had three different networking technologies
under development in the '70s, namely:
o The ARPANET; 1969 ->
o The Packet Radio Network (PRNET); 1973 ->
o A packet satellite network, called SATNET; 1976-1979"
"This implies," Spilling writes, "that the need for a protocol that would
connect these diverse networks was recognized early on and that resulted
in the paper by Cerf and Kahn, �A Protocol for Packet Network
Intercommunication.'"
Explaining the difficulty of involving different countries in the research
process, Spilling writes:
The start of the development and experimentation with SATNET was
considerably delayed. The idea was to use one 64 kb/s channel in the so
called 'Multi-destination half duplex' mode, with ground stations in
Norway, England, Germany, Italy and the USA. The endpoints of this
channel were terminated in equipment owned by different organizations.
This was unheard of in the Intelsat/Comsat organisations, and they had
no policy for handling this case � no regulations and no tariff ratings.
If I remember correctly, Bob Kahn spent a long time hammering on the
satellite organizations � more than a year � to have them accept this
new mode of operation.
Spilling explains the result of the creation of SATNET was the creation of
the INTERNET. He writes:
When SATNET development was ending in 1979 and the TCP/IP protocols were
matured sufficiently, SATNET was used as a means to interconnect local
area networks in Norway, England, Germany, and Italy with ARPANET, which
interconnected many LANs scattered all over the U.S. continent. This
constellation formed the INTERNET with capital letters, interconnecting
defence institutions and research institutions with military contracts,
hence forming a very closed community. As you have mentioned, you needed
permission from DARPA in order to connect with this community.
According to Kahn, by the 1980s there was a connection between these
different country networks using a gateway to SATNET and then a gateway to
connect to the ARPANET, "This was not a link over ARPANET," he
emphasizes(Kahn, E-mail, Sept 11, 2002), "It was a connection using
SATNET, which was a broadcast satellite system.... This is if you like an
ETHERNET IN THE SKY with drops in Norway (actually routed via Sweden) and
then the U.K. and later Germany and Italy. (Graphic IV)
Kahn explains that NDRE and UCL had been experimenting with TCP/IP before
the cutover to TCP/IP took place on the ARPANET in January 1983. Therefore
until January 1983, NDRE and UCL had two paths they would use. They could
still use NCP over the ARPANET links until they were dismantled ... and in
parallel TCP/IP could be used over SATNET. Once the ARPANET links were
dismantled, they had only the SATNET remaining." (See also From the
ARPANET to the Internet: A Study of the ARPANET TCP/IP Digest.)
http://www.ais.org/~ronda/new.papers/tcpdraft.txt
When the ARPANET nodes serving the U.K. and Norway were decommissioned,
researchers in these countries had to use TCP/IP over SATNET. Responding
to a question as to whether the 1983 cutover to TCP/IP on the ARPANET
created a new form of connection on the ARPANET, Kahn replies, "No. It was
not a new form of connection so much as it was using a different protocol
over the ARPANET (i.e. TCP/IP vs NCP) and thus, in effect, everyone on the
ARPANET was now Internet enabled since they could talk with anyone else
with TCP/IP on the Internet."
GRAPHICS
Graphic I � Diagram of NPL, CYCLADES and ARPANET as prototype for Internet
http://www.ais.org/~ronda/new.papers/1.pdf
Graphic II � Diagram of UCL, NORSAR and ARPANET links from Kirstein's 1975
paper http://www.ais.org/~ronda/new.papers/2.pdf
Graphic III � Diagram of plan for 1981 IIASA computer networking linking
research centers in Eastern and Western Europe and U.S.
http://www.ais.org/~ronda/new.papers/3.pdf
Graphic IV � SATNET as an Ethernet in the Sky http://www.ais.org
/~ronda/new.papers/4.pdf
Graphic V � 1977 Internet Experiment
http://www.ais.org/~ronda/new.papers/5.pdf
Ronda Hauben � 2004
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Reprinted from the Amateur Computerist Vol 12 No 2, Spring 2004. The
whole issue or a subscription is available for free via email. Send
a request to jrh@ais.org or see http://www.ais.org/~jrh/acn/
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