Research Of Streaming Media Scheduling Algorithm On Video-on-Demand System

In the paper,one kind of VoD scheduling algorithms,the patching scheduling algorithm,has been studied.The grouped periodic patching scheduling algorithm is put forward based on it.The main contributions of this new algorithm are as follows.First,grouped the patch streams of every period according to the arrival time.The frequency of patch stream is restircted with the method of batching and it makes the patch stream well-regulated.Second,the period of multicast stream is adjusted to the change of the request rete and the group time is adjusted to the change of the available bandwidth.Third, we merged the last group of request into the coming sharing stream so as to reduce the patch stream number much more. As the simulation experiment showed, the grouped periodic patching scheduling algorithm can sharply reduce bandwidth expense of the server in the same condition. And patch stream number in one period is much less than that of traditional periodic patching algorithm obviously.Secondly, To resolve the difficulty of speeding play and speeding back play in VoD system, a new method is put forward in this paper.