Distributed pairing for file sharing in large-scale peer-to-peer networks

Peer-to-peer systems encounter critical issues, such as peer churn, free riding, and varied workload, which significantly affect performance results such as resource utilization, service agility, and fairness. This study proposes a distributed pairing scheme that supports fast and fair file sharing applications in large-scale peer-to-peer networks. This design exploits the peer duality of both server-oriented peer capacity and client-oriented peer contribution. Accordingly, the scheme can perform peer assignment, substitution, and elimination, and cope with subtle situations of free-riding, service starvation, and download blocking, thus making the system design robust and amenable. Simulation results confirm that the proposed mechanisms are effective in maintaining service agility and fairness in large-scale, distributed peer-to-peer file sharing environments.