(redirected from Arpas)
Also found in: Dictionary, Acronyms, Wikipedia.


McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(Vostochnyi Arpachai), a river in the Armenian SSR and Nakhichevan ASSR; left tributary of the Araks. Length,

128 km; basin area, 2,630 sq km. Rises on the slopes of the Zangezur Range, flowing through an intermontane depression in its middle course. The waters of the Arpa are used for irrigation; as a result, the Arpa does not reach the Araks in the summer. The health resort of Dzhermuk is located on the river’s upper course. Construction of a tunnel (48.6 km) to divert the waters of the Arpa into Lake Sevan began in 1970.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


This article is provided by FOLDOC - Free Online Dictionary of Computing (


(Advanced Research Projects Agency NETwork) The research network funded by the U.S. Advanced Research Projects Agency (ARPA) that was the precursor to the Internet. The project was conceived in 1966 by ARPA employee Robert Taylor, who wanted to share information among researchers at major universities.

The software was developed by Bolt, Beranek and Newman (BBN), and Honeywell 516 minicomputers were the first hardware used as packet switches. ARPAnet was launched in 1969 at two University of California campuses, the Stanford Research Institute and the University of Utah.

In late 1972, the ARPAnet was demonstrated at the International Conference on Computers in Washington, DC. This was the first public demonstration of packet switching.

TCP/IP Was Added
Over the next decade, ARPAnet spawned other networks, and in 1983 with more than 300 computers connected, its protocols were changed to TCP/IP. In that same year, the unclassified military MILNET network was split off from ARPAnet.

It Became the Internet
As TCP/IP and gateway technologies matured, more disparate networks were connected, and the ARPAnet became known as "the Internet" and "the Net." Starting in 1987, the National Science Foundation began developing a high-speed backbone between its supercomputer centers. Intermediate networks of regional ARPAnet sites were formed to hook into the backbone, and commercial as well as non-profit network service providers were formed to handle the operations. Over time, other federal agencies and organizations formed backbones that linked in.

The Big Shift
In 1995, commercial Internet service providers took control of the major backbones, and the Internet grew exponentially. See Internet and packet switching.

Humble Beginnings
Scrawled on this paper in 1969 were the first four nodes of the ARPANET. Little did they realize these four nodes would grow to millions. (Image courtesy of The Computer History Museum,


(Defense Advanced Research Projects Agency) The U.S. military agency responsible for technology projects. Founded as the Advanced Research Projects Agency (ARPA) in 1958, it was renamed DARPA in 1972, then back to ARPA in 1993 and once again back to DARPA in 1996. DARPA is a small agency that assumes the role of "technological engine" for the Department of Defense and is involved in evaluating future systems. Over the years, DARPA has made huge contributions to information technology. See ARPAnet.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.