How does Videoconferencing work?
The hardware used is a video coding / decoding card (CODEC) which is installed in a Pentium based computer along with a video camera, microphone and speakers. A dedicated bandwidth of 128 Kbps or more is required over a wide area network for transporting audio and video information between the two CODECs. This network could be over an ISDN line or a satellite based leased line. Video is displayed on a TV screen and “hands free” audio communication is done using microphones and speakers. CODEC compresses the audio and video and then sends it over the high-speed link. This sound and moving image is reproduced at the remote end by another CODEC. All video conferencing systems work in a full duplex mode i.e. encoding and decoding in both directions simultaneously.
Videoconferencing technology lets people at two or more locations see and hear each other at the same time. At UA, UAB, and UAHuntsville, videoconferencing is made possible by the Intercampus Interactive Telecommunications System (IITS). This is a network of conference rooms connected to a statewide videoconferencing network. Some 30 sites throughout Alabama are equipped with cameras, monitors, and other devices that allow teachers and students to interact as if they were in the same room. Presenters use slides, overheads, and videotape as well as digital options. For more information, see the IITS page in the Distance Learning Formats section.
