Modeling analysis of server loading in large-scale P2P-VoD systems with actively collaborative helpers
Through moving a significant fraction of uploading from the servers to the peers, using P2P approach can effectively alleviate server loading in VoD deployments. However, users asynchronism dilutes their ability to assist each other. We develop a theoretical model to conduct an in-depth study of average server loading in large-scale P2P-VoD systems. This model captures many of the essential features of average server loading in large-scale P2P-VoD systems. Based on the in-depth study on average server loading, we introduce actively collaborative helpers into systems for alleviating server loading. The model of peers is further developed to a hybrid model for studying the optimal download amount of helpers from perspective of the entire network including peers and helpers. We show there exactly exists the sweet point of download amount of homogeneous helpers. With downloading the sweet amount, helpers can contribute the bandwidth around twice than they consume, when they do not assist each other, and even approximately 4 times when they assist each other.
server loading helper peer-to-peer video-on-demand