Towards Optimal Resource Utilization in Heterogeneous P2P Streaming

Though plenty of research has been conducted to improve Internet P2P streaming quality perceived by end-users, little has been known about the upper bounds of achievable performance with available resources so that different designs could compare against. On the other hand, the current practice has shown increasing demand of server capacities in P2P-assisted streaming systems in order to maintain high-quality streaming to end-users. Both research and practice call for a design that can optimally utilize available peer resources. In the paper, we first present a new design, aiming to reveal the best achievable throughput for heterogeneous P2P streaming systems. We measure the performance gaps between various designs and this optimal resource allocation. Through extensive simulations, we find out that several typical existing designs have not fully exploited the potential of system resources. However, the control overhead prohibits the adoption of this optimal approach. Then, we design a hybrid system in trading off the cost of assignment and utilization of resources. This hybrid approach has a proved theoretical bound on efficiency of utilization. Simulation results show that compared with the optimal resource allocation, our proposed hybrid design can achieve near-optimal (up to $90\%$) utilization while only use much less (below $4\%$) control overhead. Our results provide a basis for both server capacity planning in current P2P-assisted streaming practice and future protocol designs.