ARPANET - Librarians Portal

The ARPANET evolved from a series of research experiments begun in late 1960s. The Department of Defense funded research on computer networking. The research was used to try and improve military communications. The project was called the Advanced Research Projects Administration (ARPA). A wide based area network called ARPANET resulted. Networks were very fragile. Just one computer being down would cause the whole network to come down. To provide better defense, the computers were kept decentralized, so that no main computer could be disabled. In order to make this happen, a computer protocol called Transmission Control Protocol (TCP/IP) was created. The protocol worked in a manner in which if information could not get to its destination through one route, then it would automatically be rerouted through another route.

 

By 1980 ARPANET became the prototype Internet. There were 200 computers on the net. The Computer Science Network (CSNET) funded by the National Science Foundation (NSF) was then added to ARPANET. By 1983, the defense department used this combined network as its primary communications network. The number of computers connected at that time then rose to 562. In 1984, a total of 1,024 computers were linked.  In 1985, NSFNET a new network was created by the National Science Foundation. It was created to link five supercomputer centers across the country. The ARPANET was then hooked up to it, using the same protocols. The net only lasted until 1986, because the network capacity was not large enough to hold both groups. THE ARPANET was shut down very quietly and no one even noticed since the Internet was a network of networks. In 1987 Merit Network Inc. was given a contract to manage an upgrade a new network. The National Science Foundation helped with the funding to install a high speed network that used 56,000 bit per second (56 Kbps) telephone lines. This occurred in 1988. In 1988, 28,174 computers were on the Internet. In 1989 there were 80,000. In 1990- 290,000 computers were using the Internet. In 1992 a new network was built to expand the Internet. This network forms the main trunk of what is the Internet today.