Recent research efforts have demonstrated the promising potential of building cost-effective media streaming systems on top of peer-to-peer (P2P) networks. A P2P media streaming architecture can reach large size and streaming capacity that are difficult to achieve in conventional server-based streaming services. Hybrid streaming systems that combine the use of dedicated streaming servers and P2P networks were proposed to build on the advantages of both paradigms. However, the dynamics of such systems and the impact of various factors on system behaviors are not totally clear. In this paper, we present an analytical framework to quantitatively study the features of a hybrid media streaming model. Based on this framework, we derive an equation to describe the capacity growth of a single-file streaming system. We then extend the analysis to multi-file scenarios
by solving an optimization problem. We also show that the system model achieves optimal allocation of server bandwidth among different media objects. The unpredictable departure/failure of peers is a critical factor that affects performance of P2P systems. To model peer failures in our system, we propose the concept of peer lifespan. The original equation is enhanced with coefficients generated from the distribution of peer lifespan. Results from large-scale simulations support our analysis.