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ARPANET – The First Internet
was in charge of the software, and we were naturally running a
bit late. September 1 was Labor Day, so I knew I had a couple of
extra days to debug the software. Moreover, I had heard BBN was
having some timing troubles with the software, so I had some hope
they'd miss the ship date. And I figured that first some Honeywell
people would install the hardware -- IMPs were built out of Honeywell
516s in those days -- and then BBN people would come in a few days
later to shake down the software. An easy couple of weeks of grace.
fixed their timing trouble, air shipped the IMP, and it arrived
on our loading dock on Saturday, August 30. They arrived with
the IMP, wheeled it into our computer room, plugged it in and
the software restarted from where it had been when the plug was
pulled in Cambridge. Still Saturday, August 30. Panic time at
Stephen D. Crocker, The
Request For Comments Reference Guide.
The ARPANET was the first wide area packet
switching network, the "Eve" network of what has evolved into
the Internet we know and love today.
The ARPANET was originally created by the IPTO under
the sponsorship of DARPA, and conceived
and planned by Lick Licklider, Lawrence
Roberts, and others as described earlier in this section.
The ARPANET, and so the Internet, was born on August 30, 1969, when BBN delivered
the first Interface Message Processor (IMP)
Kleinrock's Network Measurements Center at UCLA. The IMP was built from
a Honeywell DDP 516 computer with 12K of memory, designed to handle the ARPANET
network interface. In a famous piece of Internet lore, on the side of the crate,
a hardware designer at BBN named Ben Barker had written "Do it to it, Truett",
in tribute to the BBN engineer Truett Thach who traveled with the computer to
UCLA on the plane.
The UCLA team responsible for installing the IMP and creating the first
ARPANET node included graduate students Vinton
Cerf, Steve Crocker, Bill Naylor, Jon
Postel, and Mike Wingfield. Wingfield had built the hardware interface
between the UCLA computer and the IMP, the machines were connected, and within
a couple of days of delivery the IMP was communicating with the local NMC host,
an SDS Sigma 7 computer running the SEX operating system. Messages were successfully
exchanged, and the one computer ARPANET was born. A picture of Leonard Kleinrock
with the first ARPANET IMP is shown below (click on the picture to link to a
larger image on Kleinrock's home site).
- Leonard Kleinrock with first IMP
The first full ARPANET network connection was next, planned to be with Douglas
Engelbart's NLS system at the Stanford Research Institute (SRI),
running an SDS-940 computer with the Genie operating system and connected
to another IMP. At about 10:30 PM on October 29'th, 1969, the connection
was established over a 50 kbps line provided by the AT&T telephone
company, and a two node ARPANET was born. As is often the case, the first
test didn't work flawlessly, as Kleinrock describes below:
At the UCLA
end, they typed in the 'l' and asked SRI if they received it; 'got
the l' came the voice reply. UCLA typed in the 'o', asked if they
got it, and received 'got the o'. UCLA then typed in the 'g' and
the darned system CRASHED! Quite a beginning. On the second attempt,
it worked fine!
- Leonard Kleinrock, The
Birth of the Internet.
Interactive Mathematics centre at the University of California at Santa
Barbara was the third site added to the ARPANET, running on an IBM 360/75
computer using the OS/MVT operating system. The fourth ARPANET site was
added in December 1969 at the University
of Utah Graphics Department, running on a DEC PDP-10 computer using
the Tenex operating system. These first four sites had been selected by
Roberts to constitute the initial ARPANET because they were already DARPA
sites, and he believed they had the technical capability required to develop
the required custom interface to the IMP.
Over the next several years the ARPANET grew rapidly. In July, 1975, DARPA
transferred management and operation of the ARPANET to the Defense Communications
Agency, now DISA.
The NSFNET then assumed management of
the non-military side of the network during its first period of very rapid
growth, including connection to networks like the CSNET and EUnet,
and the subsequent evolution into the Internet we know today.
Milestones. Some of the milestones in the early history of the ARPANET
are summarized below:
- East Coast. In March, 1970, the consulting company Bolt, Beranek & Newman
joined the ARPANET, becoming the first ARPANET node on the US east coast.
- Remote Access. In September, 1971, the first Terminal Interface
Processor (TIP) was deployed, enabling individual computer terminals to
dial directly into the ARPANET, thereby greatly increasing the ease of
network connections and leading to significant growth.
- 1972. By the end of 1972 there were 24 sites on the ARPANET, including
the Department of Defense, the National Science Foundation, NASA, and the
Federal Reserve Board.
- 1973. By the end of 1973 there were 37 sites on the ARPANET, including
a satellite link from California to Hawaii. Also in 1973, the University
College of London in England and the Royal Radar Establishment in Norway
become the first international connections to the ARPANET. A logical map of the ARPANET from 1973 can be found here.
- 1974. In June, 1974, there were 62 computers connected to the
- 1977. In March, 1977, there were 111 computers on the ARPANET. A logical map of the ARPANET from March 1977 can be found here.
- 1983. In 1983, an unclassified military only network called MILNET
split off from the ARPANET, remaining connected only at a small number
of gateways for exchange of electronic mail that could be easily disconnected
for security reasons if required. MILNET later become part of the DoD Defense
- 1985. By the middle of the 80's there were ARPANET gateways to
external networks across North America, Europe, and in Australia, and the
Internet was global in scope.
- 1990. The ARPANET was retired in 1990. Most university computers
that were connected to it were moved to networks connected to the NSFNET,
passing the torch from the old network to the new.
Resources. The following site provides more information
about the ARPANET.