A Sybil-Resilient Peer-to-Peer Network Protocol

Reciprocity technique emerges as an effective way to control freeloading problem. However, direct reciprocity schemes are not suitable for P2P networks with high churn rate; indirect reciprocity schemes are susceptible to sybil attacks. This paper presents a novel indirect reciprocity P2P protocol for limiting the capacity of sybil attacks. Our protocol accounts contributions of nodes and allows nodes to exchange contributions for obtaining services from other nodes. We model rating nodes as a shortest-paths problem in the contribution graph. As a result, our protocol is value sybilproof. The performances of our protocol has been evaluated by both theoretical analysis and simulation.