Internet prototype. A computer network developed in 1969 in the behavioral sciences division of IPTO (Information Processing Techniques Office) at the Advanced Research Projects Agency (ARPA) of the US Department of Defense. Research on the network began during the Cold War as a communication system in the event of a nuclear strike from a hypothetical enemy. Adopts a distributed model/packet switching type network, which allows communication to continue by bypassing any regions that have been attacked.