Telidon

Telidon (from the Greek words τῆλε, ''tele'' "at a distance" and ἰδών, ''idon'' "seeing") was a videotex/teletext service developed by the Canadian Communications Research Centre (CRC) during the late 1970s and supported by commercial enterprises led by Infomart in the early 1980s. The CRC referred to Telidon as a "second generation" system, offering improved performance, 2D colour graphics, multilingual support and a number of different interactivity options supported on various hardware. With additional features added by AT&T Corporation, and 16 other contributors in North America and supported by the Federal Government, Telidon was redefined as a protocol and became the NAPLPS standard.

Initially in multiple tests, Telidon failed to demonstrate compelling functionality, and the auxiliary equipment costs remained high. Although projects like GRASSROOTS for the Province of Manitoba, SOI for Venezuela, Compuserve, LA Times in California, EPIC for General Motors, NOVATEX for Teleglobe Canada and the Swiss PTT nationwide application, demonstrated the concepts, eventually government support for the project ended on 31 March 1985, and the various commercial services based on it closed shortly thereafter.

Telidon saw limited use after that, in niches like informational displays in airports and similar environments. NAPLPS did appear in several other products, notably the Prodigy online service and some bulletin boards. Telidon had a lasting legacy on the hardware side; its NABTS communications system found re-use years later in WebTV for Windows.

History

Genesis

Herb Bown is widely considered to be the "father" of Telidon. Boyko 1997. Bown had been working in the computer graphics field since the late 1960s, originally using plotters but later moving to video systems. Starting in 1970, Bown and a team at the CRC started working on a "Picture Description Instruction" (PDI) format to encode vector graphics information. An interpreter, the "Interactive Graphics Programming Language" (IGPL), read the PDI codes and rasterized them for display. By this time the team consisted of Bown, Doug O'Brien, Bill Sawchuck, J.R. Storey and Bob Warburton.

As the work continued, the team decided that locking the system to the particular hardware they were using was not appropriate, and started modifying the PDI system to be based on alphanumeric codes instead of binary numbers. A major advantage to this approach is that the data can be sent over common communications channels instead of relying on an 8-bit clean link to the host computer. In 1975 the CRC contracted Norpak to develop an interactive colour display terminal based on the new alphanumeric PDI. The CRC had patented several of the technologies by the end of 1977; a touch-sensitive input mechanism, the basic graphics system, and the interactive graphics programming language.

By the mid-1970s several European countries were in the process of introducing videotex and teletext services. There was considerable interest within the industry, and in the media, suggesting that online services would be the "next big thing". Comments to the effect that "Within the next few decades, people may be able to access much of the published information in the world from their living rooms by using videotex," were common in the trade press.

The CRC was able to interest the Department of Communications (DoC), their superiors within the federal government, to fund development of their system into the basis for a videotex service. Unlike the systems being developed in Europe and in Japan, the Canadian system would offer high-quality 2D graphics, higher speed, and could be used for one-way fixed or menued displays (teletext), two-way systems based on modems (videotex), or they could combine the two, allowing information to be sent to the customer in the video signal, and returned via modem.

Telidon development

On 15 August 1978, the DoC (whose technical side is now part of the Industry Canada) held a press conference and formally announced the Telidon project to the public, demonstrating a large video display sending information to the minicomputer controlling it over an acoustic coupler modem. They outlined a four-year development plan that included funding for further technical development at the CRC, the production of several hundred terminals that would be lent out to industry for development studies, as well as funds for marketing and lobbying in videotex standards negotiations.

In 1979 the DoC formed the Canadian Videotex Consultative Committee to advise the Minister on ways to commercialize the CRC's work, and develop videotext services within Canada. The committee held four meetings during the initial four-year development plan, and coordinated a number of field trials with broadcasters, telephone companies, cable television firms, manufacturers and various information providers. During the same period, the Task Force on Service to the Public was given the job of using Telidon as a way to provide public access to government information and services.

By late 1979 Norpak had developed a version of the Telidon decoder that was housed in a box about the size of a modern digital cable set top box. A menu selection keyset, about the size and shape of a contemporary calculator, connected to it using a ribbon cable. With the hardware in place, the CRC started working with telecommunications providers to test the system in production settings. Many of the major Canadian carriers expressed strong interest, and a number of test systems were ready to roll out by the early 1980s. Excitement was high; the 19 November 1981 issue of ''The Globe and Mail'' quoted a representative at the Canadian Computer Show and Conference in Toronto claiming that "Telidon may become as commonly used as the telephone and will have just as great a social impact." They were not alone in predicting great things for the technology:

In a radio broadcast in 1980, Douglas Parkhill, the deputy minister of research at the DoC outlined some of the potential uses, from financial information, to theatre reservations, with the ability to pay and print out tickets from the system.

Public testing

The release of Norpac's Telidon terminal led to announcements by broadcasters and news organizations who would be rolling out test systems starting late that year. However, a variety of delays pushed back most of these programs into 1980. The race to have the first operational deployment was won by the small town of South Headingley, just west of Winnipeg, part of an experimental system being deployed by the Manitoba Telephone System (MTS), the local cable operator.''Ida''

Named for Ida Cates, Manitoba's first woman telephone operator in the 1880s, "Project Ida" was part of a wider rollout of advanced cable technologies that MTS had been planning since 1978 to study ways to use up the bandwidth capabilities of newer cable systems. Services included Telidon, cable telephony, pay TV service using outdoor converters (instead of set top boxes), and low-bandwidth backchannel data services for gas and electrical billing and alarm services.''Ida''

The Telidon services that formed part of Project Ida were created by Infomart, a Toronto-based company set up to provide Telidon content. It was hosted on two computers set up in Winnipeg and run by MTS, providing a 4800 baud channel to the in-home terminals. Originally scheduled for January 1980, delays pushed this back to mid-year. Ida ran until 1981, when most of the services were dropped and the cables returned to normal analog signals, although an offshoot using optical cable was carried out in Elie, rotating the terminals though many households in the area.

Ida was followed by several Canadian companies starting similar projects. In early 1980, TVOntario, the educational television channel run by the Ontario government, set up 45 terminals in the Toronto area. In April 1981, New Brunswick Telephone set up a system practically identical to Project Ida with a full suite of services, with somewhere between 20 and 100 terminals. The same month, Alberta Government Telephones started "Project VIDON", a smaller modem-based test in the Calgary area. A month later, Bell Canada announced their "Vista" project in Toronto and Montreal, in partnership with the ''Toronto Star'' and the '' Southam Press'' who would provide content. This test eventually expanded to between 500 and 1000 terminals.Rice and Paisley, pg. 225

Telidon generated interest outside Canada as well. A major foreign sale was made in July 1980 to the government of Venezuela, who set up a test system to provide information on health, social and economic aid programs to people moving into Caracas from rural areas.

A number of U.S. companies also expressed an interest, and started plans for their own Telidon-based teletext systems. As early as 1978, AT&T Corporation and CBS had been experimenting with the idea of a videotex service, and were drawn towards the Telidon efforts. In 1982 they introduced an experimental system known as "Venture One" in Ridgewood, New Jersey

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