Research On Trust Mechanism Based On Game Theory In Opportunistic Network

In opportunistic network,information transmission depends on the chance of encounter by node movement instead of establishing end-to-end connections.The opportunity network has low dependence on the network infrastructure and can be construct automatically in the harsh network environment,which is the trend of future development of network and has became a hot spot in academic field recently.Opportunistic network has the characteristics of large transmission delay,high transmission error rate and low transmission success rate and is restricted by the node's energy,storage capacity and processing capacity and so on,therefore nodes in an opportunistic network cannot establish a fixed trust relationship.There are many problems in opportunistic network such as low transmission efficiency,low network reliability and lack of security.In this paper,we propose a trust mechanism based on Game Theory to construct trust relationships among nodes for compensating for overall performance problems.At first,an improved algorithm is proposed on the basis of the classical Epidemic routing algorithm which is named r-Epidemic routing algorithm.The designed algorithm provides a node with sufficient trusted for the node of the message source as a forwarding node for the next hop so that the message can be spread over a limited scale,which reduces the number of copies of a data packet in the network and avoids the network transmission performance degradation caused by network resource unreasonable occupation.Secondly,we propose a reliable routing model based on pricing auction transaction model.The source node is priced according to its importance,and the intermediate node bids the forwarding opportunity according to its forwarding capability.It avoids selfish nodes with lower confidence level and enhances the security and reliability of opportunistic routing under the premise of less loss network transmission performance.Finally,based on game theory,a "inverted Pyramid" classification mechanism is built in opportunistic network.According to complete information static game evaluate opportunistic routing mechanism,nodes under different game strategies gain different payoff.It optimizes the trust level of the overall network and builds trust relationships among nodes under dynamic condition which improves routing performance and routing security in opportunistic network.In this paper,through the improvement of classical routing algorithm in opportunistic network,a new trusted routing model is proposed.Then,we propose a trust mechanism based on Game Theory which is suitable for opportunistic network.The results of ONE and MATLAB simulation experiments show that our trust mechanism improves the transmission performance and routing security of opportunistic network with a certain degree and is helpful for maintaining and managing the opportunistic network in the future.