Preemption-Based Buffer Allocation in Video-on-Demand System

Present research focus is to explore several alternatives to improve the performance of a Video-on-Demand (VoD) system. The challenge in VoD application is to stream uninterrupted, synchronous and good quality multimedia data from a video server to a user over a high-speed network. Large number of concurrent users accessing a VoD system present a generic problem because of the load imposed on the video server. In this context, buffer management plays a critical role in retrieval and transfer of data. It also ensures that all the requests are guaranteed a sufficient amount of the buffer in order to improve the efficiency of the video server by reducing the initial latency. We have performed extensive analysis of the buffer requirements and conducted several runs of simulation experiment. The results show that Preemption-Based Buffer Allocation (PBBA) scheme reduces initial latency (over the number of user requests in service from one to maximum capacity) to twice that of the conventional scheme and the reneging probability is 5% to 6% with the mean reneging time of 30 seconds. The results demonstrate a significant improvement in the performance of the Video-on-Demand system.