Event-Driven Scheduling for P2P VoD

Scheduling is essential in Peer-to-Peer (P2P) Video- on-Demand (VoD) applications to obtain desirable user experience and high sharing efficiency. Existing systems and proposals largely utilize scheduling mechanisms that are periodical in nature. We refer these as time-driven scheduling. In this paper we argue that the time-driven scheduling algorithm is not efficient for P2P VoD due to its inadequate resource utilization and inability in quickly adapting to the potential dynamics in such systems. We propose an event-driven scheduling algorithm for P2P VoD systems, in which the scheduler is triggered by events such as peer churn or/and random seeks. We evaluate our design through extensive simulations, and the experimental results show that event-driven scheduling outperforms time-driven scheduling in terms of both user experience and system scalability.