Popularity Awareness in Temporal-DHT for P2P-based Media Streaming Applications

Application-layer overlay networks are receiving considerable popularity due to its flexibility and readily deployable nature thereby providing support for a plethora of Peer-to-Peer (P2P) applications. Currently, the real-world deployment of Internet-scale P2P media streaming systems involve the usage of tracker server for content discovery in on-demand model with asynchronous interactivity. The inherent drawbacks of tracker-server based approach are obvious due to scalability and bottleneck issues, which prompted us to pursue a structured P2P based proposition such as Distributed Hash Tables (DHT) which are already proved to be stable substrates. The challenging issue of accommodating a large number of update operations with the continuous change of user´s playing position in DHT-based overlay is addressed in our previous work by the concept of Temporal-DHT which exploits the temporal dynamics of the content to estimate playing position. In this paper, we incorporate the notion of popularity awareness in the Temporal-DHT framework which will help to adapt the query resolution mechanism by addressing the skew ness of content popularity typically found in real multimedia user access patterns. The essential objective of popularity awareness mechanism is to increase the overall performance of Temporal-DHT by optimizing the search cost among the entire content set within the system. We formulate the problem and provide practical solutions with extensive simulation results that demonstrates the effectiveness of popularity-aware Temporal-DHT by achieving optimized query resolution cost and high streaming quality for on-demand systems in a dynamic network environment where user´s are free to asynchronously join/leave the system.