An architecture for adaptive multimedia content delivery

In this paper, we propose an architecture for multimedia content delivery c onsidering 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 adap tation mechanism, and delivery mechanism. Applications based on current arc hitecture loses their meaning by drastically degrading quality when network congestion occurs. Despite of this all-or-nothing architecture, applicatio ns based on our adaptive architecture can reduce its quality and then negot iate with the network entity, keeping its quality measure as much as possib le even when network congestion occurs. We may consider a quality measure f or Web pages, total page transmission time, and transmission order of inlin e objects as a segregation. We then define a language to specify applicatio n level QoS policies for Web pages and implement a delivery mechanism and a QoS adaptation mechanism to fulfill these policies.