IPSANET was a

packet switching In telecommunications, packet switching is a method of grouping Data (computing), data into short messages in fixed format, i.e. ''network packet, packets,'' that are transmitted over a digital Telecommunications network, network. Packets consi ...

network Network, networking and networked may refer to: Science and technology * Network theory, the study of graphs as a representation of relations between discrete objects * Network science, an academic field that studies complex networks Mathematics ...

written by I. P. Sharp Associates (IPSA). Operation began in May 1976. It initially used the IBM 3705 Communications Controller and

Computer Automation Computer Automation, Inc. was a minicomputer and industrial control computer manufacturer founded by David H. Methvin in 1968, based originally in Newport Beach, California, United States.Datamation, June 1968 p.167 It opened a sales, support a ...

LSI-2 computers as

node In general, a node is a localized swelling (a "knot") or a point of intersection (a vertex). Node may refer to: In mathematics * Vertex (graph theory), a vertex in a mathematical graph *Vertex (geometry), a point where two or more curves, lines ...

s. An

Intel 80286 The Intel 80286 (also marketed as the iAPX 286 and often called Intel 286) is a 16-bit microprocessor that was introduced on February 1, 1982. It was the first 8086-based CPU with separate, non- multiplexed address and data buses and also the f ...

based-node was added in 1987. It was called the Beta node. The original purpose was to connect low-speed

dumb terminal A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. Most early computers only had a front panel to input or display ...

s to a central

time sharing In computing, time-sharing is the concurrent sharing of a computing resource among many tasks or users by giving each task or user a small slice of processing time. This quick switch between tasks or users gives the illusion of simultaneous ...

host in Toronto. It was soon modified to allow a terminal to connect to an alternate host running the SHARP APL software under license. Terminals were initially either 2741-type machines based on the 14.8 characters/s

IBM Selectric typewriter The IBM Selectric (a portmanteau of "selective" and "electric") was a highly successful line of electric typewriters introduced by IBM on 31 July 1961. Instead of the "basket" of individual typebars that swung up to strike the ribbon and page ...

or 30 character/s ASCII machines. Link speed was limited to 9600 bit/s until about 1984. Other services including 2780/3780

Bisync Binary Synchronous Communication (BSC or Bisync) is an IBM character-oriented, half-duplex link protocol, announced in 1967 after the introduction of System/360. It replaced the synchronous transmit-receive (STR) protocol used with second gener ...

support, remote printing,

X.25 X.25 is an ITU-T standard protocol suite for Packet switched network, packet-switched data communication in wide area network, wide area networks (WAN). It was originally defined by the CCITT, International Telegraph and Telephone Consultative Co ...

gateway and SDLC pipe lines were added in the 1978 to 1984 era. There was no general purpose data transport facility until the introduction of ''Network Shared Variable Processor'' (NSVP) in 1984. This allowed APL programs running on different hosts to communicate via Shared Variables. The Beta node improved performance and provided new services not tied to APL. An

interface was the most important of these. It allowed connection to a host which was not running SHARP APL. IPSANET allowed for the development of an early yet advanced

e-mail Electronic mail (usually shortened to email; alternatively hyphenated e-mail) is a method of transmitting and receiving Digital media, digital messages using electronics, electronic devices over a computer network. It was conceived in the ...

service, ''666 BOX'', which also became a major product for some time, originally hosted on IPSA's system, and later sold to end users to run on their own machines. NSVP allowed these remote e-mail systems to exchange traffic. The network reached its maximum size of about 300 nodes before it was shut down in 1993.

External links

IPSANET Archives
{{Webarchive, url=https://web.archive.org/web/20210225174511/http://www.rogerdmoore.ca/INF/ , date=2021-02-25 Computer networking Packets (information technology)