How Darpa created the Internet worldwide

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The foundation of the current internet started taking shape in 1969 with the activation of the four-node network, known as ARPANET, and matured over two decades until ARPANET was deactivated as it became subsumed by the much more extensive network of networks, that is, the internet.Jul 9, 2020

ARPANET - Darpa

Defense Advanced Research Projects Agency (.mil)

https://www.darpa.mil › ARPANET_final

 

ARPANET
Advancing National Security Through Fundamental Research

THE NEED AND
OPPORTUNITY
DARPA research played a central
role in launching the information
revolution, including furthering much
of the conceptual basis for today’s
internet – a ubiquitous, global network
for sharing digital resources among
geographically separated computers.
The world-changeing consequences of
the research continue to unfold on a
daily basis.
The roots of the modern internet lie in
the groundbreaking work DARPA began
in the 1960s under program manager
Joseph Carl Robnett Licklider to create
what became the ARPANET. At the time,
the agency was known as the Advanced
Research Projects Agency, or ARPA. In
its earliest form, the ARPANET began
with four computer nodes, and the first
computer-to-computer signal on this
nascent network was sent between
UCLA and the Stanford Research
Institute on Oct. 29, 1969.
Secure communications and
information-sharing between
geographically dispersed research
facilities were among the ARPANET’s
original goals. As more computers
became involved in this early computer
network, however, engineering
problems arose. A key issue was
maintaining communications,
because if the ARPANET behaved like
a traditional circuit-based telephone
system, failure of a single node could
take down the entire network.
What was needed was a means to get
messages to their destination in a way
that did not depend on any single node.
This is the challenge that spawned
the concept of packet switching.
By moving packets of data that
dynamically worked their way through
a network to the destination where
they would reassemble themselves,
it became possible to avoid losing
data even if one or more nodes went
down. A common communications
protocol between computers was also
necessary, because the computers
involved were not always compatible.
Building a protocol and the software
that would allow different computers to
communicate and “internetwork” was a
significant challenge.
THE DARPA SOLUTION
The ARPANET was established in
the last months of the 1960s, but
the first major demonstration of its
networking capabilities took place in
Washington D.C., in 1972. At this time,
the Department of Defense (DoD)
became interested in using computers
for command and control. Unlike
the ARPANET, which used dedicated
phone lines to connect computer
facilities together, the military wanted
a mobile network to link tanks, planes,
ships, and other assets together. That
capability required the use of radio and
satellite systems.
By 1973, DARPA-supported researchers
had come up with four different packet-
switching technologies, which led to the
next challenge: to develop standards
that would enable these separate
communications technologies to, in
turn, communicate with each other. Dr.
Vint Cerf, who was at Stanford
University at the time and working
on contract for DARPA, recalls that
it took about six months of work to
develop the right system architecture
and create a rough protocol for
controlling and managing the packet
traffic.He and Robert Kahn, then
the director of DARPA’s Information
Processing Techniques Office (IPTO)
and who in 1976 hired Cerf as a
program manager, began work on
what would become the Transmission
Control Protocol (TCP) and the Internet
Protocol (IP).
The initial implementation of the first
TCP/IP protocol occurred at Stanford in
1975. As testing progressed the next
few years, the now-famous protocol was
being implemented on an exponentially
growing number of computer systems
around the world. In January 1983,
enough individual networks had
networked with each other that the
ARPANET had evolved into the internet,
although the original ARPANET itself
was not formally decommissioned until
1990.
By the early 1980s, the bones of what
would become the internet were in
place. This new and growing network,
with continued support by DARPA
and DoD, became available to the
academic community, which led to the
launch of other government networks.
Multiple geographically
dispersed nodes
Significant expansion across
U.S. military bases, government
labs, and universities
Switch to Transmission Control
Protocol (TCP) and the Internet
Protocol (IP) (TCP/IP)
ARPANET Ended
1969 1970 1977 1983 1989
The foundation of the current internet started taking shape in 1969 with the activation of the four-node network, known as ARPANET, and matured over two
decades until ARPANET was deactivated as it became subsumed by the much more extensive network of networks, that is, the internet.
Prominent among these was NSFnet,
which the National Science Foundation
established in 1985 to further the
causes of advanced research and
education.
In 1988, Cerf, who was then vice
president of the Corporation for
National Research Initiatives,
received permission from the Federal
Networking Council to connect the
MCI Mail service, which had been
providing commercial email services
over phone lines via modem since
1983, to the computer-based
internet. As president of MCI’s Digital
Information Services from 1982 to
1986, Cerf had led the development
of MCI Mail. This authorization served
to break the restriction prohibiting
commercial electronic communications
from traveling over the government
backbone. With service beginning in
1989, this new commercial, rather
than government-based, email service
opened the floodgates for other
commercial players. The major email
providers of the time (including AOL,
CompuServe, and Telenet’s Telemail),
which were providing messaging via
telephone modems, followed MCI
Mail’s lead and shifted their traffic
to the emerging internet. This rapid
expansion of commercial internet
services prompted the NSF to shut
down its dedicated backbone in 1995.
In the mid-1990s, DARPA sought
to build on this rapid technology
development and deployment by
delivering internet applications
that would make possible
secure, dependable battlefield
communications. The key issue was
that unlike the civilian internet, a
military network could not depend on
fixed infrastructure such as cell towers,
routers, and server farms, partly
because these fixed nodes would be
prime and easy targets on a battlefield
and partly because such infrastructure
probably would not be available where
and when it was needed.
What was needed was a mobile
network. Toward that end, DARPA-
backed research helped create a
network of devices, including laptop
ARPANET
One of the many essential steps in the creation
of what would become known as the internet
occurred in 1968 when ARPA contracted BBN
Technologies to build the first routers, known
as Interface Message Processors or IMPs, which
enabled ARPANET to become operational the
following year. (Photo courtesy of Steve Jurvetson
under a CC BY 2.0 license)
THE EVOLUTION OF ARPANET

www.darpa.mil
computers and mobile phones, which
did not require a fixed infrastructure.
Instead, each mobile device could
send and receive information from
one another. Should one device be
lost to the network, many others would
still be available to send and receive
data. Scaled upward from a local area
network, the concept paved the way for
“mesh networks.”
THE IMPACT
In military contexts, mesh networks
undergirded the implementation of a
series of operational communications
systems, among them Common Data
Link (CDL), the Tactical Common Data
Link (TCDL), and Tactical Targeting
Network Technology (TTNT).
For the civilian world, mesh networks
would mean investing less in expensive
and vulnerable infrastructure, and
instead in building networks that were
cheaper and more robust. Perhaps
more importantly, such networks could
deliver the internet to large swaths
of the world that still lacked access.
An increasingly consequential benefit
of mesh networks is that they enable
various devices on the Internet of
Things (IoT) – things like thermostats,
home automation systems,
vehicles, and wearable devices – to
communicate with each other as
well as provide connectivity for more
devices that might be too far away from
an internet service provider.
In figures cited by the Congressional
Research Service, the number of IoT
devices in 2019 is likely to grow from
the nearly 10 billion that were active in
2019 to more than 21 billion by 2025.
This explosion of devices creates both
great benefits and great challenges.
The IoT depends upon making the data
of those connecting devices accessible
to IoT companies and storable in the
cloud. This raises issues of privacy
and security, as well as of citizens’
ownership and control of their own
data.
LOOKING AHEAD
Today, DARPA’s internet-related
research addresses concerns regarding
autonomy, security, and privacy. The
DARPA program Brandeis, for example,
centers on breaking the tension
between maintaining privacy and being
able to tap into the huge value of data.
Rather than having to balance between
them, Brandeis aims to enable safe
and predictable sharing of data in
which privacy is preserved. Programs
such as Explainable AI seek to develop
automated tools that explain how
artificial intelligence systems arrive at
conclusions and make decisions.
A goal here is to develop foundations
of trust in AI as it becomes more
prevalent. Another program, Media
Forensics (MediFor), is investigating
the capability to automatically detect
manipulations of online imagery
and to reveal precisely how these
manipulations were performed.
Though the internet’s increasing
ubiquity brings a mix of promise and
peril, today it has in many ways fulfilled
Licklider’s vision of “the main and
essential medium of informational
interaction for governments,
institutions, corporations, and
individuals.” He sent that forward-
looking vision to his colleagues nearly
sixty years ago in a now famous memo
to the ARPA research community on
April 25, 1963. This year, according to
the technology firm Cisco, some 5.3
exabytes (1018 bytes) of data traffic will
course the internet each day, a rate
equivalent to transmitting every movie
ever made every two minutes.
This historic log entry for the Interface Message
Processor (IMP) at UCLA records the first
ARPANET message on 10/29/1969, at 22:30 Pacific
Time, from Boelter Hall 3420. On the cover page
of this vignette is a “back-of-the-napkin” sketch
(from December 1969) of the nascent ARPANET
and its four original nodes.