Abstract: To resolve the problem of "free riding" and "tragedy of the commons" in peer-to-peer live streaming systems, a cooperation model was proposed in a game theoretic framework. The proportional fairness optimal strategy was proved under Nash equilibrium and Pareto optimality. And then the corresponding node behavior strategy was analyzed considering their cheating behaviors. Finally, the analytical results show that the model can effectively stimulate node cooperation and prevent cheating.

Key words: Peer-to-Peer (P2P) network, game theory, incentive mechanism, Nash equilibrium, Pareto optimality

摘要： 针对P2P实时流环境中出现的“搭便车”和“公共悲剧”问题,提出一种博弈论框架下的激励合作模型。分析该模型达到Nash均衡和Pareto最优状态下对应的比例公平策略优化。并考虑存在欺骗行为的情况,研究对应的节点行为策略。理论分析表明,该模型能够刺激节点合作,并且对节点的欺骗行为具有抑制作用。

关键词: 对等网络, 博弈论, 激励机制, Nash均衡, Pareto最优