Multiple-tree topology construction scheme for P2P live streaming systems under flash crowds

P2P live streaming systems have been widely adopted nowadays. In such systems, flash crowds still remains a big challenge, which often occur when an enormous number of users suddenly arrive to view a newly released program. In a flash crowd scenario, users often suffer from a long startup delay and a high failure rate. In this paper, we propose a topology-construction-based algorithm to alleviate the flash crowd. Specifically, first the tracker server constructs a multiple tree topology with total new peers. Then according to the topology, all new peers join the current P2P system in form of multiple trees. When constructing the topology, the tracker server puts new peers with higher bandwidth and longer waiting time more closer to the root in each tree, in order to reduce the average waiting time of new peers. Moreover, a new analytical model is also devised to evaluate our algorithm. Model analysis and simulation indicate that our method can enhance the joining process of new peers and improve their startup delay and failure rate.