Information Technology Reference
In-Depth Information
simply the calculating element in control systems. Instead it became
understood as a more general symbolic machine, concerned with
the interactive manipulation of information. In practical terms the
work on Whirlwind and SAGE entailed the development of many
technologies that later became standard parts of modern comput-
ing. Indeed Whirlwind and SAGE can be said to have determined
much of the structure both technically and conceptually of con-
temporary digital technology. Among specific technologies it made
possible or helped develop were magnetic memory, video displays,
effective computer languages, graphic display techniques, simula-
tion techniques, analogue-to-digital and digital-to-analogue con-
version techniques, multiprocessing, and networking.
In particular the SAGE / Whirlwind project was crucial in the
development of 'real-time' computing in which messages could
be responded to almost immediately. This was an extraordinary
advance compared to the batch-processing model most commonly
employed in computing at the time, which still used the punched
card technology first developed at the beginning of the nineteenth
century. 'Real time' computing was clearly a fundamental require-
ment for any use of computing in the hair-trigger matter of nuclear
defence. It also necessitated rethinking not just the technology but
also the whole way in which computers were used and understood.
It was these kinds of issues and concerns that led to the formation
of ARPA, the Advanced Research Projects Agency (later known as
DARPA, the Defense Advanced Research Projects Agency). This was
a body set up in
by the Eisenhower administration as a response
to Sputnik, and the Soviet scientific advance that represented.
26
As
a government agency ARPA was unusual, in that it had a broad
mandate, and almost no accountability. It was thus able to support
high-risk projects over a long time. Partly through the gift from
the Director of Defense Research and Engineering of a powerful
computer built as backup for SAGE, which was surplus to require-
ments, ARPA became involved in researching military applications
1958
