Secure Communication in Two-Hop Buffer-Aided Networks with Limited Packet Lifetime

Abstract

This paper investigates the buffer-aided relay selection for achieving physical layer security (PLS) in two-hop wireless networks. Available works only focus on networks with infinite packet lifetime. However, the more practical scenario with limited packet lifetime are largely ignored. We consider in this paper a two-hop wireless system where every packet transmitted over the network has a limited lifetime. We first proposed a novel buffer-aided relay selection scheme to select the best relay based on lifetime of packets in the relay buffer. We then analyze the secrecy outage probability (SOP) and the expected queuing delay of the network. Finally, we provide extensive numerical results to investigate the SOP and delay performances. The results showed that the SOP decreases as the maximum packet lifetime increases, while the average queuing delay increases as the maximum packet lifetime increases.