Interactive Videoconferencing (IV) is an tool that can be effectively applied in distance education and can be incorporated into the distance education program. There should be an interaction between video and audio interaction. IV systems use digital video for the transmission of motion images over data networks with high capacity known as Integrated Services Digital Networks (ISDN). During the video compression, the quantity of transmitted data and its cost reduces. The transmitting of interactive videoconferences is performed through dedicated T-1 phone lines that possess high speed. The operation of interactive videoconferencing systems is performed at various data rates and fractions of T-1 capacity. Interactive videoconferencing makes the connection of two locations performed with sophisticated computer technology possible. Interactive videoconferencing is performed with the electronic device responsible for transmitting and receiving of video signals that can be seen on their television monitors. The codec is a modem with complicated structure that receives digital data, compresses, digitizes and transmits it over constant digital phone lines. It is useful to know that such kinds of instructional equipment as television monitors, videocassette recorders/players, microphones, cameras and computers can be applied to make interactive videoconferencing more effective. Multiple telephone lines make possible the connection of some sites thanks to apply of a multi-point control unit in the same conference. Multi-point conferencing has proved its effectiveness.
Interactive video has proved its effectiveness because it:
- makes the contact “students – instructor”, “students – students” performed at sides possible.
- applies various kinds of diverse media such as blackboards, handwritten documents, and videos.
- makes the connection with experts located in various geographical locations possible.
- can be applied by at-risk or special needs students.
- can be used by students at remote sites.
Interactive video is limitated because:
- the access to the equipment and leasing the lines for the transmitting of conferences is reduced.
- codecs possess developed unique methods of compression that cannot be comparewith each other.
- handwritten or copied materials cannot be easily read and cause misunderstanding while reading.
- the pipe responsible for the transmission among sites is small and leads to the observation of ghost images, because of rapid movement.
- the system configured inproperly leads to an audio echo effect.
There are various kinds of videoconferencing systems:
- Small room videoconferencing those purpose is to serve small groups (the number of participants is from1 to 12) at all sites that are located around a conference table.
| 
