Bringing studio quality video-conferences to wide area IP networks with an adaptation layer translator (ALX)

High quality videoconferencing is an efficient tool for interactive scientific collaboration. With the wide deployment of broadband wide area IP networks such as Intemet2, there is an increasing demand for improved remote collaboration using these networks. In order to make the high quality videoconferencing toolkits for local high-speed networks available over wide area IP networks, issues that are usually insignificant on local area networks must be considered. In this paper, we describe a high quality videoconferencing system we developed based on an earlier version of the system for local area networks. To solve the problems associated with real-time video and audio transmission over wide area IP networks, we added a specifically design hardware device called an adaptation layer translator (ALX). A conference control protocol based on a channel rotation scheme is also developed to coordinate the participants in an ALX-based conference.