Secrecy Capacity Maximization for Secure Cooperative Ad-hoc Networks

This paper investigates secure cooperative communication with the involvement of multiple malicious eavesdroppers. By characterizing the security performance of the system by secrecy capacity, we study the secrecy capacity maximization problem in cooperative communication aware ad hoc networks. Specifically, we propose a system model where secrecy capacity enhancement is achieved by the assignment of cooperative relays. We theoretically present a corresponding formulation for the problem and discuss the security gain brought by the relay assignment process. Then, we develop an optimal relay assignment algorithm to solve the secrecy capacity maximization problem in polynomial time. The basic idea behind our proposed algorithm is to boost the capacity of the primary channel by simultaneously decreasing the capacity of the eavesdropping channel. To further increase the system secrecy capacity, we exploit the jamming technique and propose a smart jamming algorithm to interfere the eavesdropping channels. Analysis and experimental results reveal that our proposed algorithms significantly increase the system secrecy capacity under various network settings.