High quality P2P-Video-on-Demand with download bandwidth limitation

Abstract

This paper investigates a VoD distribution architecture that exploits the increasing uplink and local storage capacities of customer equipment in a peer-to-peer (P2P) manner in order to offload the central video servers and the core network segment. We investigate an environment where (i) the peers' upload speeds vary in time and (ii) on the subscriber's downlink a strict bandwidth limit constrains the VoD delivery, and where (iii) this downlink limit is not significantly higher than the video's own bit rate while (iv) the subscribers' upload capacities are not cut down. In such an environment providing quality for a true VoD service requires carefully selected mechanisms. We show how the components (storage policy, uplink speed management) of a P2P-VoD system should be changed to be feasible under these conditions. The main component of the system determines the minimal required server speed as a function of the prebuffered content, the uploaders' behaviours, and the given play back fault probability. Additionally, by using simulation we investigate the optimal downlink bandwidth limit for a subscriber population with different average upload speeds.