Jamming Mitigation via Hierarchical Security Game for IoT Communications

In the Internet of Things (IoT), the malicious node with sensorial capability can smartly launch jamming attacks only when it detects the legitimate transmission, known as the reactive jamming. Compared with the conventional constant jamming model, the reactive nature enables highly efficient and long-lasting attacks with limited energy supply, which thus presents a significant threat upon the secure communications in IoT. In this paper, we investigate the anti-reactive-jamming transmission strategy for IoT by exploiting the inherent weakness of the jammer. Specifically, since the reactive jamming depends on the detection of the legitimate transmission, the legitimate user can elaborately determine its transmit power to tradeoff between its achieved signal-to-interference-plus-noise ratio and the probability to be detected and jammed by its adversary. Meanwhile, the jammer can smartly allocate the jamming power based on its observation of the legitimate transmission. We formulate the rivalry between the legitimate user and jammer as a hierarchical game, where the legitimate user takes action first as the leader while the jammer is the follower. We analyze the game equilibrium for both single-channel and multi-channel scenarios and derive the optimal transmission and jamming strategies for the legitimate user and jammer, respectively. Finally, we present the numerical results to evaluate the performance of the secure IoT communications under our proposal.