Videoconferencing uses voice and video communication, usually over digital
transmission systems (ISDN, dedicated channels, fiber optics, or satellite
communications). A coder/decoder (CODEC) digitizes the audio and video before
transmission, compresses the data to fit the transmission system, and converts the
incoming audio and video from digital to analogue at the remote sites. Videoconferencing
systems range from large-scale, fixed installations—often used for live
video-lecturing to large audiences with one-way video and two-way audio—to
point-to-point desktop systems on personal computers linked by networks. Recent
improvements in video compression technology, together with lower-cost equipment and
transmission (such as by public ISDN), have made two-way "compressed
videoconferencing" affordable for classrooms, businesses, and small colleges. This
technology fills a niche between the very expensive traditional systems and desktop
conferencing on personal computers.
More on videoconferencing
SAIDE. 1998. The Distance
Education Practices of The Wits P&DM Master of Management Programme in Mpumalanga, SAIDE:
Johannesburg
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