An architecture for adaptive multimedia content delivery

In this paper, we propose an architecture for multimedia content delivery considering Quality of Service (QoS), based on both the policy-based network and the best-effort network. The architecture consists of four fundamental elements: multimedia content model, application level QoS policy, QoS adaptation mechanism, and delivery mechanism. Applications based on current architecture loses their meaning by drastically degrading quality when network congestion occurs. Despite of this all-or-nothing architecture, applications based on our adaptive architecture can reduce its quality and then negotiate with the network entity, keeping its quality measure as much as possible even when network congestion occurs. We may consider a quality measure for Web pages, total page transmission time, and transmission order of inline objects as a segregation. We then define a language to specify application level QoS policies for Web pages and implement a delivery mechanism and a QoS adaptation mechanism to fulfill these policies. Kaname Harumoto, Ph.D.: He received the M.E. and Ph.D. (Eng.) degrees from Osaka University, Osaka, Japan, in 1994 and 1998, respectively. From 1994 through 1999, he was with the Department of Information Systems Engineering, Grauuate School of Engineering, Osaka University. Since November 1999, he has been an Assistant Professor in Computation Center (currently, the name has changed to Cybermedia Center), Osaka University. His research interests include database systems, especially in advanced network environments. He is a member of IEEE. Tadashi Nakano: He received the B.E. degree from Osaka University in 1999. Currently, he is a Ph.D. candidate in Graduate School of Engineering, Osaka University. His current reeearch interests include multimedia content delivery architecture. Shinji SHIMOJO, Ph.D.: He received the M.E. and a Dr.E. degrees from Osaka University in 1983 and 1986, respectively. From 1986 through 1989, he was an Assistant Professor in the Department of Information and Computer Sciences, Faculty of Engineering Science, Osaka University. From 1989 through 1998, he was an Associate Professor and since 1998, he has been a Professor in Computation Center (currently, the name has changed to Cybermedia Center), Osaka University. He was engaged in the project of object-oriented multimedia presentation system called Harmony. His current interests cover wide diversity of multimedia applications such as News On Demand System, multimedia database and networked virtual reality. He is a member of ACM and IEEE.