Abstract :
The efficient design of next-generation wireless systems faces multifaceted problems involving a variety of node types such as wireless users, relay stations, base stations, eavesdroppers, and jammers. In this paper, the complex decision making processes between a network of wireless users that perform uplink transmission via relay stations and an active malicious node, that is able to act as an eavesdropper and as a jammer, is studied. A noncooperative game in which the users and the malicious node are the players is formulated. On the one hand, the users seek to choose the relay station that maximizes their utilities which reflect their mutual interference as well as the security of the chosen path. On the other hand, the objective of the malicious node is to choose whether to eavesdrop, jam, or use a combination of both strategies, in a way to reduce the total network capacity. To solve the game, a fictitious play-based algorithm is proposed using which the users and the malicious node reach a mixed-strategy Nash equilibrium. Simulation results show that the proposed approach improves the average expected utility per user up to 49.4% relative to a nearest neighbor algorithm. The results also show how the malicious node can strategically decide on whether to jam or eavesdrop depending on its capabilities and objectives.