Abstract: The existing studies on the game model of P2P nodes do not take into account diversity of nodes types,complexity of node strategies, and asymmetry of node information. This paper presents a game model of combination strategy for routing nodes in P2P networks. In this model, routing nodes are divided into two types, namely good nodes and bad nodes. They are also categorized as end nodes and middle nodes according to their positions in the routing process. The corresponding strategies adopted by each type of nodes at each routing stage are defined as combination strategies of routing nodes. Based on such strategies, this paper analyzes payoff matrixes of the games among various node strategies, and derives transfer conditions of different combination strategies in the game model with asymmetric information and betrayal of routing nodes.

Key words: peer-to-peer network, routing node, type, combined strategy, game model