Analysis of overlay topology of peer-to-peer applications

With the ever growing usage of peer-to-peer (P2P) technology, more and more P2P applications emerge on Internet. Based on purely distributed architecture of basic P2P, many new architecture and strategies are developed to improve quality of experience (QoE) of P2P applications. Peer to server and peer (P2SP) architecture is used by Thunder, while UUSee combines content delivery network (CDN) and P2P architecture. Understanding the characteristics of different P2P architectures is important for service provisioning and network optimization. In this paper, based on a large sample of flow data collected from operational network, we study overlay topology properties of different P2P applications from complex network perspective, including BT, Thunder, and UUSee. The overlay topology is modeled as a weighted directed graph, and degree distribution, reachability and PageRank distribution are analyzed. Analysis results show different characteristics of P2P applications, which indicate different quality of experience.