WAN Technologies : ARPANET

<h3>WAN Technologies: ARPANET</h3>One of the oldest wide area technologies, the ARPANET, was funded by ARPA, the Advanced Research Projects Agency. ARPA awarded a contract for the development of the ARPANET to Bolt, Beranek and Newman of Cambridge, MA in the fall of 1968. By September 1969, the first pieces of the ARPANET were in place.

The ARPANET served as a testbed for much of the research in packet switching. In addition to its use for network research, researchers in several universities, military bases, and government labs regularly used the ARPANET to exchange files and electronic mail and to provide remote login among their sites. In 1975, control of the network was transferred from ARPA to the U.S. Defense Communications Agency (DCA).

The DCA made the ARPANET part of the Defense Data Network @DN), a program that provides multiple networks as part of a world-wide communication system for the Department of Defense.

In 1983, the Department of Defense partitioned the ARPANET into two connected networks, leaving the ARPANET for experimental research and forming the MILNET for military use. MILNET was restricted to unclassified data because it was not considered secure. Although under normal circumstances, both ARPANET and MILNET agreed to pass traffic to each other, controls were established that allowed them to be disconnected?. Because the ARPANET and MILNET used the same hardware technology, our description of the technical details apply to both. In fact, the technology was also available commercially and was used by several corporations to establish private packet switching networks.

Because the ARPANET was already in place and used dily by many of the researchers who developed the Internet architecture, it had a profound effect on their work. They came to think of the ARPANET as a dependable wide area backbone around which the Internet could be built.