The Internet has revolutionized the computer and communications
world like nothing before. The invention of the telegraph, telephone, radio,
and computer set the stage for this unprecedented integration of capabilities.
The Internet is at once a world-wide broadcasting capability, a mechanism for
information dissemination, and a medium for collaboration and interaction
between individuals and their computers without regard for geographic location.
The Internet represents one of the most successful examples of the benefits of
sustained investment and commitment to research and development of information
infrastructure. Beginning with the early research in packet switching, the
government, industry and academia have been partners in evolving and deploying
this exciting new technology. Today, terms like
"bleiner@computer.org" and "http://www.acm.org" trip
lightly off the tongue of the random person on the street. 1
This is intended to be a brief, necessarily cursory and incomplete
history. Much material currently exists about the Internet, covering history,
technology, and usage. A trip to almost any bookstore will find shelves of
material written about the Internet. 2
In this paper,3 several of us involved in the development
and evolution of the Internet share our views of its origins and history. This
history revolves around four distinct aspects. There is the technological
evolution that began with early research on packet switching and the ARPANET
(and related technologies), and where current research continues to expand the
horizons of the infrastructure along several dimensions, such as scale,
performance, and higher-level functionality. There is the operations and
management aspect of a global and complex operational infrastructure. There is
the social aspect, which resulted in a broad community of Internauts working
together to create and evolve the technology. And there is the
commercialization aspect, resulting in an extremely effective transition of
research results into a broadly deployed and available information
infrastructure.
The Internet today is a widespread information infrastructure, the
initial prototype of what is often called the National (or Global or Galactic)
Information Infrastructure. Its history is complex and involves many aspects -
technological, organizational, and community. And its influence reaches not
only to the technical fields of computer communications but throughout society
as we move toward increasing use of online tools to accomplish electronic
commerce, information acquisition, and community operations.
The first recorded description of the social interactions that
could be enabled through networking was a series of memos written
by J.C.R. Licklider of MIT in August 1962 discussing his "Galactic
Network" concept. He envisioned a globally interconnected set of computers
through which everyone could quickly access data and programs from any site. In
spirit, the concept was very much like the Internet of today. Licklider was the
first head of the computer research program at DARPA,4 starting in October 1962. While at DARPA
he convinced his successors at DARPA, Ivan Sutherland, Bob Taylor, and MIT
researcher Lawrence G. Roberts, of the importance of this networking concept.
Leonard Kleinrock at MIT published the first paper
on packet switching theory in July 1961 and the first book on the
subject in 1964. Kleinrock convinced Roberts of the theoretical
feasibility of communications using packets rather than circuits, which was a
major step along the path towards computer networking. The other key step was
to make the computers talk together. To explore this, in 1965 working with
Thomas Merrill, Roberts connected the TX-2 computer in Mass. to the Q-32 in
California with a low speed dial-up telephone line creating the first (however small) wide-area computer network ever
built. The result of this experiment was the realization that the
time-shared computers could work well together, running programs and retrieving
data as necessary on the remote machine, but that the circuit switched
telephone system was totally inadequate for the job. Kleinrock's conviction of
the need for packet switching was confirmed.
In late 1966 Roberts went to DARPA to develop the computer network
concept and quickly put together his plan for the
"ARPANET", publishing it in 1967. At the conference where
he presented the paper, there was also a paper on a packet network concept from
the UK by Donald Davies and Roger Scantlebury of NPL. Scantlebury told Roberts
about the NPL work as well as that of Paul Baran and others at RAND. The RAND
group had written a paper on packet switching networks for secure voice in
the military in 1964. It happened that the work at MIT (1961-1967), at RAND
(1962-1965), and at NPL (1964-1967) had all proceeded in parallel without any
of the researchers knowing about the other work. The word "packet" was
adopted from the work at NPL and the proposed line speed to be used in the
ARPANET design was upgraded from 2.4 kbps to 50 kbps. 5
In August 1968, after Roberts and the DARPA funded community had
refined the overall structure and specifications for the ARPANET, an RFQ was
released by DARPA for the development of one of the key components, the packet
switches called Interface Message Processors (IMP's). The RFQ was won in
December 1968 by a group headed by Frank Heart at Bolt Beranek and Newman
(BBN). As the BBN team worked on the IMP's with Bob Kahn playing a major role
in the overall ARPANET architectural design, the network topology and economics
were designed and optimized by Roberts working with Howard Frank and his team
at Network Analysis Corporation, and the network measurement system was
prepared by Kleinrock's team at UCLA. 6
Due to Kleinrock's early development of packet switching theory
and his focus on analysis, design and measurement, his Network Measurement
Center at UCLA was selected to be the first node on the ARPANET. All this came
together in September 1969 when BBN installed the first IMP at UCLA and the
first host computer was connected. Doug Engelbart's project on
"Augmentation of Human Intellect" (which included NLS, an early hypertext
system) at Stanford Research Institute (SRI) provided a second node. SRI
supported the Network Information Center, led by Elizabeth (Jake) Feinler and
including functions such as maintaining tables of host name to address mapping
as well as a directory of the RFC's.
One month later, when SRI was connected to the ARPANET, the first
host-to-host message was sent from Kleinrock's laboratory to SRI. Two more
nodes were added at UC Santa Barbara and University of Utah. These last two
nodes incorporated application visualization projects, with Glen Culler and
Burton Fried at UCSB investigating methods for display of mathematical
functions using storage displays to deal with the problem of refresh over the
net, and Robert Taylor and Ivan Sutherland at Utah investigating methods of 3-D
representations over the net. Thus, by the end of 1969, four host computers
were connected together into the initial ARPANET, and the budding Internet was
off the ground. Even at this early stage, it should be noted that the
networking research incorporated both work on the underlying network and work
on how to utilize the network. This tradition continues to this day.
Computers were added quickly to the ARPANET during the following
years, and work proceeded on completing a functionally complete Host-to-Host
protocol and other network software. In December 1970 the Network Working Group
(NWG) working under S. Crocker finished the initial ARPANET Host-to-Host
protocol, called the Network Control Protocol (NCP). As the ARPANET sites
completed implementing NCP during the period 1971-1972, the network users
finally could begin to develop applications.
In October 1972, Kahn organized a large, very successful
demonstration of the ARPANET at the International Computer Communication
Conference (ICCC). This was the first public demonstration of this new network
technology to the public. It was also in 1972 that the initial "hot"
application, electronic mail, was introduced. In March Ray Tomlinson at BBN
wrote the basic email message send and read software, motivated by the need of
the ARPANET developers for an easy coordination mechanism. In July, Roberts
expanded its utility by writing the first email utility program to list,
selectively read, file, forward, and respond to messages. From there email took
off as the largest network application for over a decade. This was a harbinger
of the kind of activity we see on the World Wide Web today, namely, the
enormous growth of all kinds of "people-to-people" traffic.
