Realization of Large-Scale Distributed Systems Robust Against Selfish User Behavior

我将P2P文件共享系统作为大规模分布式系统的一个例子，并研究了自私用户行为与系统性能之间的关系。首先在博弈论的框架下对自私用户行为进行建模，然后借助进化博弈论揭示自私用户之间的互动对系统性能的影响。通过数学分析和仿真评估，当每个用户理性行为时，我们可以实现抗文件丢失的健壮的文件共享系统，而与用户的自私程度无关：只有当文件可能在没有他/她的帮助的情况下从网络中消失时，他/她才会保存和共享该文件。

I focused on P2P file-sharing systems as an example of large-scale distributed systems and examined the relationship between selfish user behavior and system performance. I first made modeling of the selfish user behavior under the framework of game theory, then revealed how the interactions among selfish users affects the system performance with the help of evolutionary game theory. Through mathematical analyses and simulation evaluations, we can achieve robust file-sharing systems against file disappearance independent of the degree of user selfishness when each user rationally behaves : He/she keeps and shares a file only when the file is likely to disappear from the network without his/her help.