ABSTRACT
This chapter discusses three different categories of relay and jammer selection schemes to improve the physical layer security of two-way cooperative networks. These categories are selection schemes without jamming, selection schemes with conventional jamming, and selection schemes with controlled jamming. Due to the broadcast nature of wireless communication networks, the adversarial nodes "eavesdroppers" can intercept transmissions in their coverage area and try to recover parts of the transmitted message. The chapter focuses on the impact of changing both the eavesdroppers and the intermediate nodes location on the system performance. It also discusses the impact of the presence of multiple cooperating and noncooperating eavesdroppers on system performance metrics. The chapter describes the network model and formulates the problem. The hybrid scheme which switches between jamming and nonjamming selection schemes is proposed to overcome jamming limitations and seems to be an efficient solution for practical applications with critical secrecy constraints.
