Research Assistants: M. Annamalai, S. Li, S. Wang, D. Wang, W. Wang
Sponsors: AT&T, NSF, PRF
Emerging applications of distributed systems allow geographically distributed users to exchange data in multiple media, such as video, audio, image, drawing, and text, over communication channels. The video and/or audio data provide new challenges because these require systems to continuously transmit large amounts of data over networks with possibly a large number of sites in real-time. Traditional communication protocols such as TCP and UDP are not well suited for delivering multimedia (especially continuous media) data over the wide area network such as the Internet. The focus of our research is the design and development of new communication protocols for multimedia applications. In the protocol design, we are focusing on the reliability and real-time aspects and on mechanisms of guaranteeing application-level quality of services (QoS) for packet video on the Internet. We have implemented an adaptable video conferencing tool on the Internet that can dynamically and automatically adapt itself to available network bandwidth while still maintaining certain levels of application-level quality of services. We have also investigated techniques to improve the performance of a distributed video-on-demand system. We are incorporating the adaptability features that can dynamically change the size, color and resolution of a video frame to meet the quality of services requirements of a single user or video conferencing session.