History of Video Conferencing ?

Didyou history know video chatconferencing ? if you don’t know wikipedia will explain and told you aboutvideoconferencing, this is history :

Videoconferencinguses telecommunications of audio and video to bring people at different sitestogether for a meeting. This can be as simple as a conversation between twopeople in private offices (point-to-point) or involve several sites(multi-point) with more than one person in large rooms at different sites.Besides the audio and visual transmission of meeting activities,videoconferencing can be used to share documents, computer-displayedinformation, and whiteboards.

Simpleanalog videoconferences could be established as early as the invention of thetelevision. Such videoconferencing systems usually consisted of twoclosed-circuit television systems connected via coax cable or radio. An exampleof that was the German Reich Postzentralamt (Post Office) network set up inBerlin and several other cities from 1936 to 1940.

Duringthe first manned space flights, NASA used two radiofrequency (UHF or VHF)links, one in each direction. TV channels routinely use this kind ofvideoconferencing when reporting from distant locations, for instance. Thenmobile links to satellites using specially equipped trucks became rathercommon.

Thistechnique was very expensive, though, and could not be used for applicationssuch as telemedicine, distance education, and business meetings. Attempts atusing normal telephony networks to transmit slow-scan video, such as the firstsystems developed by AT&T, failed mostly due to the poor picture qualityand the lack of efficient video compression techniques. The greater 1 MHzbandwidth and 6 Mbit/s bit rate of Picturephone in the 1970s also did not causethe service to prosper.

To be continued ....