On client interactive behaviour to design peer selection policies for BitTorrent-like protocols

Abstract

Peer-to-peer swarming protocols have been proven to be very efficient for content replication over Internet. This fact has certainly motivated proposals to adapt these protocols to meet the requirements of on-demand streaming system. The vast majority of these proposals focus on modifying the piece and peer selection policies, respectively, of the original protocols. Nonetheless, it is true that more attention has often been given to the piece selection policy rather than to the peer selection policy. Within this context, this article proposes a simple algorithm to be used as basis for peer selection policies of BitTorrent-like protocols, considering interactive scenarios. To this end, we analyze the client interactive behaviour when accessing real multimedia systems. This analysis consists of looking into workloads of real content providers and assessing three important metrics, namely temporal dispersion, spatial dispersion and object position popularity. These metrics are then used as the main guidelines for writing the algorithm. To the best of our knowledge, this is the first time that the client interactive behaviour is specially considered to derive an algorithm for peer selection policies. Finally, the conclusion of this article is drawn with key challenges and possible future work in this research field.