Re-exploring the Potential of Using Tree Structure in P2P Live Streaming Networks

The current peer-to-peer (P2P) live streaming networks can be generally classified into two categories: tree-based and data-driven. The tree-based approach suffers from three limitations: interruptive delivery due to failures of high level nodes, unfair uploading (out-going) bandwidth utilization in leaf nodes and bandwidth bottleneck in nodes near the root. The data driven approach has been widely studied recently to tackle the defects of the tree-based approach mentioned above. However the tree-based approach still has its advantages: deterministic delivery path length and predictable delay, and natural support to PUSH mode content delivery. Because of these advantages the tree-based approach will not be simply replaced by the data-driven approach. Based on this consideration, we propose a cluster-based approach to remedy the disadvantages of the normal tree-based approach and meanwhile retain its advantages as much as possible. By grouping peers into clusters, the content delivery tree constructed by clusters can maintain a stable overlay structure and transmission direction in a dynamic network environment. Simulation results show that our approach can effectively overcome the shortages of the single tree-based approach and outperform the data-driven approach in terms of deterministic content delivery path and predictable path length.