10 August 2009
A worldwide network of interlocking computer
systems, developed out of a U.S. government project to improve
The people behind the invention:
Paul Baran, a researcher for the RAND corporation
Vinton G. Cerf (1943- ), an American computer scientist
regarded as the “father of the Internet”
Cold War Computer Systems
In 1957, the world was stunned by the launching of the satellite
Sputnik I by the Soviet Union. The international image of the United
States as the world’s technology superpower and its perceived edge
in the ColdWar were instantly brought into question. As part of the
U.S. response, the Defense Department quickly created the Advanced
Research Projects Agency (ARPA) to conduct research into
“command, control, and communications” systems. Military planners
in the Pentagon ordered ARPA to develop a communications
network that would remain usable in the wake of a nuclear attack.
The solution, proposed by Paul Baran, a scientist at the RAND Corporation,
was the creation of a network of linked computers that
could route communications around damage to any part of the system.
Because the centralized control of data flow by major “hub”
computers would make such a system vulnerable, the system could
not have any central command, and all surviving points had to be
able to reestablish contact following an attack on any single point.
This redundancy of connectivity (later known as “packet switching”)
would not monopolize a single circuit for communications, as
telephones do, but would automatically break up computer messages
into smaller packets, each of which could reach a destination
by rerouting along different paths.
ARPA then began attempting to link university computers over
telephone lines. The historic connecting of four sites conducting
ARPAresearch was accomplished in 1969 at a computer laboratory
at the University of California at Los Angeles (UCLA), which was
connected to computers at the University of California at Santa
Barbara, the Stanford Research Institute, and the University of Utah.
UCLA graduate student Vinton Cerf played a major role in establishing
the connection, which was first known as “ARPAnet.” By
1971, more than twenty sites had been connected to the network, including
supercomputers at the Massachusetts Institute of Technology
and Harvard University; by 1981, there were more than two
hundred computers on the system.
The Development of the Internet
Because factors such as equipment failure, overtaxed telecommunications
lines, and power outages can quickly reduce or abort
(“crash”) computer network performance, the ARPAnet managers
and others quickly sought to build still larger “internetting” projects.
In the late 1980’s, the National Science Foundation built its
own network of five supercomputer centers to give academic researchers
access to high-power computers that had previously been
available only to military contractors. The “NSFnet” connected university
networks by linking them to the closest regional center; its
development put ARPAnet out of commission in 1990. The economic
savings that could be gained from the use of electronic mail
(“e-mail”), which reduced postage and telephone costs, were motivation
enough for many businesses and institutions to invest in
hardware and network connections.
The evolution of ARPAnet and NSFnet eventually led to the creation
of the “Internet,” an international web of interconnected government,
education, and business computer networks that has been
called “the largest machine ever constructed.” Using appropriate
software, a computer terminal or personal computer can send and
receive data via an “Internet Protocol” packet (an electronic envelope
with an address). Communications programs on the intervening
networks “read” the addresses on packets moving through the
Internet and forward the packets toward their destinations. From
approximately one thousand networks in the mid-1980’s, the Internet
grew to an estimated thirty thousand connected networks by
1994, with majority of Internet users live in the United States and Europe, but
the Internet has continued to expand internationally as telecommunications
lines are improved in other countries.
Most individual users access the Internet through modems attached
to their home personal computers by subscribing to local area
networks. These services make information sources available such as
on-line encyclopedias and magazines and embrace electronic discussion
groups and bulletin boards on nearly every specialized interest
area imaginable. Many universities converted large libraries to electronic
form for Internet distribution, with an ambitious example being
Cornell University’s conversion to electronic form of more than
100,000 books on the development of America’s infrastructure.
Numerous corporations and small businesses soon began to
market their products and services over the Internet. Problems soon
became apparent with the commercial use of the new medium,
however, as the protection of copyrighted material proved to be difficult;
data and other text available on the system can be “downloaded,”
or electronically copied. To protect their resources from
unauthorized use via the Internet, therefore, most companies set up
a “firewall” computer to screen incoming communications.
The economic policies of the Bill Clinton administration highlighted
the development of the “information superhighway” for
improving the delivery of social services and encouraging new
businesses; however, many governmental agencies and offices, including
the U.S. Senate and House of Representative, have been
slow to install high-speed fiber-optic network links. Nevertheless,
the Internet soon came to contain numerous information sites to improve
public access to the institutions of government.
are improved in other countries.
Although Vinton Cerf is widely hailed as the “father of the
Internet,” he himself disavows that honor. He has repeatedly
emphasized that the Internet was built on the work of countless
others, and that he and his partner merely happened to make a
crucial contribution at a turning point in Internet development.
The path leading Cerf to the Internet began early. He was
born in New Haven, Connecticut, in 1943. He read widely, devouring
L. Frank Baum’s Oz books and science fiction novels—
especially those dealing with real-science themes. When he was
ten, a book called The Boy Scientist fired his interest in science.
After starting high school in Los Angeles in 1958, he got his first
glimpse of computers, which were very different devices in
those days. During a visit to a Santa Monica lab, he inspected a
computer filling three rooms with wires and vacuum tubes that
analyzed data from a Canadian radar system built to detect
sneak missile attacks from the Soviet Union. Two years later he
and a friend began programming a paper-tape computer at
UCLA while they were still in high school.
After graduating from Stanford University in 1965 with a
degree in computer science, Cerf worked for IBM for two years,
then entered graduate school at UCLA. His work on multiprocessing
computer systems got sidetracked when a Defense
Department request came in asking for help on a packet-switching
project. This new project drew him into the brand-new field
of computer networking on a system that became known as the
ARPAnet. In 1972 Cerf returned to Stanford as an assistant professor.
There he and a colleague, Robert Kahn, developed the
concepts and protocols that became the basis of the modern Internet—
a term they coined in a paper they delivered in 1974.
Afterward Cerf made development of the Internet the focus
of his distinguished career, and he later moved back into the
business world. In 1994 he returned to MCI as senior vice president
of Internet architecture. Meanwhile, he founded the Internet
Society in 1992 and the Internet Societal Task Force in 1999.
See also: Cell phone; Communications satellite; Fax machine;