Virtual Conferencing Glossary

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V.35 - An ITU-T standard that governs synchronous data transmission at 48kbps. In practice, V.35 is used for syn-chronous transmission to 2048 Mbps.

VGA - Stands for Video Graphics Array. The default resolution for VGA is 640x480. Higher resolutions of 800x600, 1024x768, and 1280x1024 are known as ‘super’ VGA.

Video bridge - Computerized switching system which allows multipoint videoconferencing.

Video conferencing - Communication across long distances with video and audio contact that may also include graphics and data exchange. Digital video transmission systems typically consist of camera, codec (coder-decoder), network access equipment, network, and audio system. Videoconferencing is the process of conducting a conference between two or more people at different locations by using computer networks to transmit audio and video data.

Video follows voice - The concept of a videoconferencing system that automatically points the camera at the person speaking.

Video overlay - The combining of multiple images in a mosaic fashion. In broadcast television, a common example is that of showing a forecaster in front of a weather map. In computer-based videoconferencing, a common example is that of showing a video image of people in front of a computer-generated image.

Video Server - A specialised file server with enormous hard disc capacities (often measured in terabytes or trillions of bytes). These servers store MPEG compressed audio and video images and provide service to end-users over high-speed LANs and WANs. Applications that require video servers include entertainment, train-ing/education, and video-enabled databases.

Virtual conferencing - Virtual conferencing is a term used to describe the wide array of conferencing technologies available today. Audio conferencing, video conferencing, data conferencing and web conferencing are all examples of virtual conferencing. In it’s most simplistic form, when two people are talking on the telephone, they are in a virtual meeting. As soon as three or more people are involved in the same telephone conversation, a virtual confer-ence is in play. The same holds true for a video or web conference.

Voice activated switching - Refer to multipoint conferences where the sites generally display the video from the site with the strongest audio signal, with that site seeing video from the previously selected site.

VOIP (Voice Over IP) - Short for Voice over Internet Protocol. It includes any technology that enables voice telephony over IP Networks. If Voice Over IP is used in a private setting such as Intranet or WAN it is generally referred to as VoIP. If it is transported over the public Internet it is referred to as Internet telephony.

VSAT - Very small aperture terminal. Refers to small satellite earth station, usually in the 1.2 to 2.4 meter range.