Incentive Routing Design for Covert Communication in Multi-hop Decentralized Wireless Networks

In this paper, we focus on a multi-hop decentralized wireless network consisting of legitimate nodes, adversary wardens, and friendly but selfish jammers, and investigate the routing design for achieving covert communication. For a pair of source and destination nodes, we first provide theoretical analysis for a given route between them to reveal how the covertness performance is related to the jamming power of jammers in the network. Then, we design an incentive mechanism that stimulates selfish jammers to supply artificial jamming to protect communication covertness, by granting them rewards from the source. A two-stage Stackelberg game framework is developed to analyze the strategic interactions between the source and jammers, and so as to determine the optimal settings of rewards and jamming power. Based on these results, we formulate a shortest weighted path-finding problem to identify the optimal route for covert communication between the source and destination, which can be solved efficiently by employing Dijkstra's algorithm. Simulation results demonstrate the performance of the proposed incentive routing scheme.

I. Introduction

With the rapid evolution of wireless communication technologies, an unprecedented increasing amount of data is transmitted over wireless networks and systems, and meanwhile, people are paying more and more attention to wireless communication security [1]. Due to the open propagation characteristics of wireless media, malicious eavesdroppers and adversary wardens are able to access the transmitted signals relatively easily, which may create huge security vulnerabilities. However, among the well-known security technologies, neither the traditional information encryption technology [2] nor the new physical layer security (PLS) technology [3] can completely solve the privacy problem, because eavesdroppers/wardens can obtain key encrypted information by analyzing the intercepted traffic data.