On Blocking Probability Evaluation for Video-on-Demand Systems

In this paper, we develop three explicit analytical models for evaluating the request blocking probability of movie files in VoD systems under three server selection schemes. The first is exact and the other two are based on fixed point approximations. We show that the choice of server selection schemes can significantly affect the blocking probability performance of the systems. We demonstrate by simulation that the models accurately predict the overall file request blocking probability in the systems and the blocking probability of the requests for single-copy files. Comparisons among the three server selection schemes are performed. Observations are presented and intuitively explained.