Videoconferencing

The Rise and Fall of the Picturephone

The story of videoconferencing began in the United States in the 1920s, when Bell Labs connected two callers between Washington, D.C., and New York City) and continued during the 1930s in Europe, where television technologies were more mature. By 1964, AT&T was ready to introduce its first public videoconferencing tool—the Picturephone—at the World's Fair. After spending $500 million on development and predicting one million users by 1980, AT&T was stunned when the Picturephone turned out to be a financial failure, garnering only 200 subscribers.

Some researchers have suggested that the Picturephone failed because people simply dislike face-to-face communication via telephone. Others maintained that it was wrongly designed for one-to-one communication, whereas “multipoint” communication (à la conference calls) is how most businesses conduct remote conferencing. As industry expert James [Page 464]Wilcox explains, much of the 1970s and 1980s was spent developing multipoint technologies, with British Telecom persuading telephone companies around Europe to conduct country-to-country trials of equipment. These trials paved the way for the videoconferencing interoperability standards that exist today, and allow multipoint videoconferencing like Stanford's “virtual auditorium” project.

A video conference. (Robert Llewellyn/CORBIS)

From Toy to Tool

In its early days, videoconferencing seemed to many to be more a high-tech toy than a necessary communications tool: Videoconferences could be conducted only out of specially equipped rooms costing from $250,000 to $1,000,000 or more. It was only after the arrival of low-cost solid-state memory in the late 1980s that “set-top” systems started becoming available, with prices at a more manageable $10,000 or so. Set-tops, often configured as rolling carts, were responsible for broadening videoconferencing's uses beyond the traditional office. Director Peter Jackson recently used it to coordinate multiple film crews shooting Lord of the Rings (2001) in remote New Zealand locations, and President George W. Bush conducts videoconferences with his advisers in Washington on days when he is at his Texas ranch.

Whether room-based or set-top, the mechanics of videoconferencing are the same. First, analog signals from video cameras and microphones are translated to digital information inside one's home computer. This is done by way of a codec (a truncated combination of the words “compression” and “decompression”), a compression and decompression standard that is often called the heart of a videoconferencing system. Codecs, which can be either hardware or software, compress outgoing information so it can be quickly and successfully sent via telephone connections; later, the codec decompresses incoming information for viewing. Finally, if multipoint videoconferencing is desired, an expensive multipoint processing unit, sometimes called a “bridge,” must also be implemented. Although another solution, called “multicasting,” does exist, it is not technically feasible for most users today.

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