A study on repeat-request chunks in pull-based peer-to-peer video-on-demand streaming

For content delivery in P2P video streaming systems there are two main approaches: push-based and pull-based. In pull-based P2P video streaming, neighbor peers request missed chunks of video from each other, but sometimes peers can´t receive this chunks because of the exit or delay of the corresponding neighbor. Although previous works such as forward error correction (FEC) and automatic repeat request (ARQ) have paid attention to detecting and repairing bit errors in network packets and also packet loss, they haven´t considered lost chunks occurred due to churn in overlay. In this paper we study repeat-request challenges and propose two new application layer methods for repeat-requesting lost chunks based on repairing the errors of neighbors´ exits and repeat-requesting the delayed chunks in pull-based P2P video on demand streaming systems. In addition in order to use these methods we propose an exit management method. We evaluate the performance of our methods via network simulation and the results showed that by using our methods we can achieve better quality of service.