Streaming over subscription overlay networks

A subscription overlay network (SON) consists of a stream source server and a number of subscribing nodes that pay monthly fee to watch the program. While the video program is continuous and endless, a subscriber typically watches the program only in some time interval. Thus, a SON may have a large number of subscribing nodes, but at any one time, only a small percentage of them may be playing (i.e., receiving some program) while many others are just idling. In this paper, we consider how these idling nodes can be leveraged for constructing highly efficient overlay multicast, where clients can join and leave dynamically. Unlike regular playing nodes, an idling node should be included in a multicast tree only when doing so can improve the system performance (e.g., reducing network traffic). We address this challenge and propose a novel overlay multicast technique that is able to find and incorporate appropriate idling nodes for data forwarding. We evaluate the performance of the proposed technique through simulation, and the results confirm its performance advantages.