A Brief History of the Internet and Related Networks
In 1973, the U.S. Defense Advanced Research Projects Agency (DARPA)
initiated a research program to investigate techniques and technologies for
interlinking packet networks of various kinds. The objective was to develop
communication protocols which would allow networked computers to
communicate transparently across multiple, linked packet networks. This
was called the Internetting project and the system of networks which
emerged from the research was known as the "Internet." The system of
protocols which was developed over the course of this research effort
became known as the TCP/IP Protocol Suite, after the two initial protocols
developed: Transmission Control Protocol (TCP) and Internet Protocol (IP).
In 1986, the U.S. National Science Foundation (NSF) initiated the
development of the NSFNET which, today, provides a major backbone
communication service for the Internet. With its 45 megabit per second
facilities, the NSFNET carries on the order of 12 billion packets per month
between the networks it links. The National Aeronautics and Space
Administration (NASA) and the U.S. Department of Energy contributed
additional backbone facilities in the form of the NSINET and ESNET
respectively. In Europe, major international backbones such as NORDUNET
and others provide connectivity to over one hundred thousand computers
on a large number of networks. Commercial network providers in the U.S.
and Europe are beginning to offer Internet backbone and access support on
a competitive basis to any interested parties.
"Regional" support for the Internet is provided by various consortium
networks and "local" support is provided through each of the research and
educational institutions. Within the United States, much of this support has
come from the federal and state governments, but a considerable
contribution has been made by industry. In Europe and elsewhere, support
arises from cooperative international efforts and through national research
organizations. During the course of its evolution, particularly after 1989,
the Internet system began to integrate support for other protocol suites into
its basic networking fabric. The present emphasis in the system is on
multiprotocol interworking, and in particular, with the integration of the
Open Systems Interconnection (OSI) protocols into the architecture.
Both public domain and commercial implementations of the roughly 100
protocols of TCP/IP protocol suite became available in the 1980's. During
the early 1990's, OSI protocol implementations also became available and,
by the end of 1991, the Internet has grown to include some 5,000 networks
in over three dozen countries, serving over 700,000 host computers used by
over 4,000,000 people.
A great deal of support for the Internet community has come from the U.S.
Federal Government, since the Internet was originally part of a
federally-funded research program and, subsequently, has become a major
part of the U.S. research infrastructure. During the late 1980's, however,
the population of Internet users and network constituents expanded
internationally and began to include commercial facilities. Indeed, the bulk
of the system today is made up of private networking facilities in
educational and research institutions, businesses and in government
organizations across the globe.
The Coordinating Committee for Intercontinental Networks (CCIRN), which
was organized by the U.S. Federal Networking Council (FNC) and the
European Reseaux Associees pour la Recherche Europeenne (RARE), plays
an important role in the coordination of plans for government- sponsored
research networking. CCIRN efforts have been a stimulus for the support
of international cooperation in the Internet environment.
Internet Technical Evolution
Over its fifteen year history, the Internet has functioned as a collaboration
among cooperating parties. Certain key functions have been critical for its
operation, not the least of which is the specification of the protocols by
which the components of the system operate. These were originally
developed in the DARPA research program mentioned above, but in the last
five or six years, this work has been undertaken on a wider basis with
support from Government agencies in many countries, industry and the
academic community. The Internet Activities Board (IAB) was created in
1983 to guide the evolution of the TCP/IP Protocol Suite and to provide
research advice to the Internet community.
During the course of its existence, the IAB has reorganized several times.
It now has two primary components: the Internet Engineering Task Force
and the Internet Research Task Force. The former has primary
responsibility for further evolution of the TCP/IP protocol suite, its
standardization with the concurrence of the IAB, and the integration of
other protocols into Internet operation (e.g. the Open Systems
Interconnection protocols). The Internet Research Task Force continues to
organize and explore advanced concepts in networking under the guidance
of the Internet Activities Board and with support from various government
A secretariat has been created to manage the day-to-day function of the
Internet Activities Board and Internet Engineering Task Force. IETF meets
three times a year in plenary and its approximately 50 working groups
convene at intermediate times by electronic mail, teleconferencing and at
face-to-face meetings. The IAB meets quarterly face-to-face or by
videoconference and at intervening times by telephone, electronic mail and
Two other functions are critical to IAB operation: publication of documents
describing the Internet and the assignment and recording of various
identifiers needed for protocol operation. Throughout the development of the
Internet, its protocols and other aspects of its operation have been
documented first in a series of documents called Internet Experiment Notes
and, later, in a series of documents called Requests for Comment (RFCs).
The latter were used initially to document the protocols of the first packet
switching network developed by DARPA, the ARPANET, beginning in 1969,
and have become the principal archive of information about the Internet.
At present, the publication function is provided by an RFC editor.
The recording of identifiers is provided by the Internet Assigned Numbers
Authority (IANA) who has delegated one part of this responsibility to an
Internet Registry which acts as a central repository for Internet information
and which provides central allocation of network and autonomous system
identifiers, in some cases to subsidiary registries located in various
countries. The Internet Registry (IR) also provides central maintenance of
the Domain Name System (DNS) root database which points to subsidiary
distributed DNS servers replicated throughout the Internet. The DNS
distributed database is used, inter alia, to associate host and network
names with their Internet addresses and is critical to the operation of the
higher level TCP/IP protocols including electronic mail.
There are a number of Network Information Centers (NICs) located
throughout the Internet to serve its users with documentation, guidance,
advice and assistance. As the Internet continues to grow internationally,
the need for high quality NIC functions increases. Although the initial
community of users of the Internet were drawn from the ranks of computer
science and engineering, its users now comprise a wide range of disciplines
in the sciences, arts, letters, business, military and government
In 1980-81, two other networking projects, BITNET and CSNET, were
initiated. BITNET adopted the IBM RSCS protocol suite and featured direct
leased line connections between participating sites. Most of the original
BITNET connections linked IBM mainframes in university data centers.
This rapidly changed as protocol implementations became available for
other machines. From the beginning, BITNET has been multi-disciplinary
in nature with users in all academic areas. It has also provided a number
of unique services to its users (e.g., LISTSERV). Today, BITNET and its
parallel networks in other parts of the world (e.g., EARN in Europe) have
several thousand participating sites. In recent years, BITNET has
established a backbone which uses the TCP/IP protocols with RSCS-based
applications running above TCP.
CSNET was initially funded by the National Science Foundation (NSF) to
provide networking for university, industry and government computer
science research groups. CSNET used the Phonenet MMDF protocol for
telephone-based electronic mail relaying and, in addition, pioneered the first
use of TCP/IP over X.25 using commercial public data networks. The
CSNET name server provided an early example of a white pages directory
service and this software is still in use at numerous sites. At its peak,
CSNET had approximately 200 participating sites and international
connections to approximately fifteen countries.
In 1987, BITNET and CSNET merged to form the Corporation for Research
and Educational Networking (CREN). In the Fall of 1991, CSNET service
was discontinued having fulfilled its important early role in the provision
of academic networking service. A key feature of CREN is that its
operational costs are fully met through dues paid by its member