摘要

In on-demand video streaming system, periodic broadcast technique scheme has been shown to be very effective for serving a popular video in reducing the demand on server bandwidth. On the contrary, reactive server transmission approach is more suitable for the video that is not popular enough. However, the level of demand on a video may change by time. In this paper, we propose a segment-based patching scheme which allocates adaptively transmission resources according to the varying client request rate. Our technique smoothly adjusts itself to cope with the changing workloads. The scheme tries to dynamically search the optimal number of channels assigned to the video by the newly updated request rate so as to minimize the bandwidth requirement. We also show how to seamlessly perform the transition of changing the number of channels with the guarantee that the clients viewing this video will not experience any disruption. Simulation results indicate that the scheme adapts very well to the changing client request rate and improves the system performance significantly in terms of the total server bandwidth requirement.