Sustainable Cooperation in Peer-To-Peer Networks

TL;DR

This paper introduces a novel peer-to-peer cooperation mechanism that rewards sustained cooperation, effectively counters selfish behavior, and maintains system fairness and performance with minimal overhead, validated through large-scale deployment and simulation.

Contribution

It presents a new local evaluation-based protocol that resists Sybil and misreporting attacks, promoting cooperation without global accountability mechanisms.

Findings

Sustains cooperation with majority selfish peers

Operates with negligible overhead

Validated on large-scale deployment and simulation

Abstract

Traditionally, peer-to-peer systems have relied on altruism and reciprocity. Although incentive-based models have gained prominence in new-generation peer-to-peer systems, it is essential to recognize the continued importance of cooperative principles in achieving performance, fairness, and correctness. The lack of this acknowledgment has paved the way for selfish peers to gain unfair advantages in these systems. As such, we address the challenge of selfish peers by devising a mechanism to reward sustained cooperation. Instead of relying on global accountability mechanisms, we propose a protocol that naturally aggregates local evaluations of cooperation. Traditional mechanisms are often vulnerable to Sybil and misreporting attacks. However, our approach overcomes these issues by limiting the benefits selfish peers can gain without incurring any cost. The viability of our algorithm is proven with a deployment to 27,259 Internet users and a realistic simulation of a blockchain gossip protocol. We show that our protocol sustains cooperation even in the presence of a majority of selfish peers while incurring only negligible overhead.