Game Theoretical Analysis on Cooperation Stability and Incentive Effectiveness in Community Networks

Community networks, the distinguishing feature of which is membership admittance, appear on P2P networks, social networks, and conventional Web networks. Joining the network costs money, time or network bandwidth, but the individuals get access to special resources owned by the community in return. The prosperity and stability of the community are determined by both the policy of admittance and the attraction of the privileges gained by joining. However, some misbehaving users can get the dedicated resources with some illicit and low-cost approaches, which introduce instability into the community, a phenomenon that will destroy the membership policy. In this paper, we analyze on the stability using game theory on such a phenomenon. We propose a game-theoretical model of stability analysis in community networks and provide conditions for a stable community. We then extend the model to analyze the effectiveness of different incentive policies, which could be used when the community cannot maintain its members in certain situations. Then we verify those models through a simulation. Finally, we discuss several ways to promote community network’s stability by adjusting the network’s properties and give some proposal on the designs of these types of networks from the points of game theory and stability.以成员准入机制为核心特征的社区网络，广泛存在于对等网络（P2P）、社交网络以及传统万维网中。用户加入该网络需付出金钱、时间或网络带宽成本，但作为回报，可获取社区专属资源。社区的繁荣与稳定性，同时取决于准入政策与加入后可获得的特权吸引力。然而，部分行为不端的用户可通过非法且低成本的手段获取专属资源，这会为社区引入不稳定因素，进而破坏社区的准入规则。针对该现象，本文基于博弈论展开稳定性分析，提出了一种用于社区网络稳定性分析的博弈论模型，并给出了社区实现稳定所需的条件；随后将该模型拓展，用于分析不同激励政策的有效性——这类政策可在社区无法在特定场景下维系成员时启用；之后通过仿真实验对所提模型进行验证；最后探讨了通过调整网络属性以提升社区网络稳定性的多种路径，并从博弈论与稳定性视角出发，为这类网络的设计提供若干建议。