Active adaptation by program delegation in video on demand

In order to provide more flexibility and a richer set of capabilities to support dynamic adaptive control of QoS in distributed multimedia systems, this paper seeks to complement the conventional passive data passing paradigm with the active program passing approach. By delegating and redelegating on the fly adaptation programs to encapsulate desired feedback control intelligence and data, a fine-grained, customizable and dynamic adaptation to QoS variations becomes realizable. To validate our approach, we built an experimental prototype that utilizes the above active adaptation paradigm to regulate video flow for video on demand. Preliminary results show a viable system which has much greater flexibility for adaptation than is traditionally possible.