video conferencing equipments

A videoconference (also known as a videoteleconference) is a set of interactive telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously. It has also been called visual collaboration and is a type of groupware.

History

Simple analog videoconferences could be established as early as the invention of the television. Polycom Sound Station Standard. Such videoconferencing systems consisted of two closed-circuit television systems connected via cable. During the first manned space flights, NASA used two radiofrequency (UHF or VHF) links, one in each direction. TV channels routinely use this kind of videoconferencing when reporting from distant locations, for instance. Then mobile links to satellites using special trucks became rather common.

This technique was very expensive, though, and could not be used for more mundane applications, such as telemedicine, distance education, business meetings, and so on, particularly in long-distance applications.