In mobile networks, cooperative authentication is an efficient way to recognize false identities and messages. However, an attacker can track the location of cooperative mobile nodes by monitoring their communications. Moreover, mobile nodes consume their own resources when cooperating with other nodes in the process of authentication. These two factors cause selfish mobile nodes not to actively participate in authentication. In this paper, a bargaining-based game for cooperative authentication is proposed to help nodes decide whether to participate in authentication or not, and our strategy guarantees that mobile nodes participating in cooperative authentication can obtain the maximum utility, all at an acceptable cost. We obtain Nash equilibrium in static complete information games. To address the problem of nodes not knowing the utility of other nodes, incomplete information games for cooperative authentication are established. We also develop an algorithm based on incomplete information games to maximize every node's utility. The simulation results demonstrate that our strategy has the ability to guarantee authentication probability and increase the number of successful authentications.

In MANETs, cooperative authentication, requiring cooperation of neighbor nodes, is a significant authenticate technique. However, when nodes participate in cooperation, their location may easily be tracked by misbehaving nodes, meanwhile, their resources will be consumed. These two factors lead selfish nodes reluctant participate in cooperation and decrease the probability of correct authentication. To encourage nodes to take part in cooperation, we proposed a bargaining-based dynamic game model for cooperative authentication to analyze dynamic behaviors of nodes and help nodes decide whether to participate in cooperation or not. Further, to analyze the dynamic decision-making of nodes, we discussed two situations - complete information and incomplete information, respectively. Under complete information, Sub game Perfect Nash Equilibriums are obtained to guide nodes to choose its optimal strategy to maximize its utility. In reality, nodes often do not have good knowledge about others' utility (this case is often called incomplete information). To dealt with this case, Perfect Bayesian Nash Equilibrium is established to eliminate the implausible Equilibriums. Based on the model, we designed two algorithms for complete information and incomplete information,, and the simulation results demonstrate that in our model nodes participating in cooperation will maximize their location privacy and minimize their resources consumption with ensuing the probability of correct authentication. Both of algorithms can improve the success rate of cooperative authentication and extend the network lifetime to 160%-360.6%.

In MANET, the cooperative authentication mechanism requires the cooperation of the neighbor nodes and significantly enhances the authentication probability. However, it exposes location privacy of neighbor nodes and is costly. How to balance the authentication and location privacy is a key issue. In this paper, we use game theory to analyze the behavior of neighbor nodes in cooperative authentication and gain the optimal strategy. Every node seeks to obtain most reward at least location privacy loss and cost. We first build the static game with complete information and obtain two pure-strategy and one mixed-strategy Nash equilibria. These equilibria can be used efficiently to balance authentication and location privacy. Then, we build the static game with incomplete information and obtain the Bayesian Nash equilibria.