Cooperative Key Establishment Protocol for Full-Duplex Relay Systems

Using the fading channel characteristics, as a randomness source, for the secret key generation earns significant attention because of it’s computational less power and low energy consumption. Current researches focus on point-to-point reciprocal-based key extraction from these randomness sources. Most practical communication situations are non-line of sight, so endpoints use a relaying channel to improve communication performance. Besides that, in the upcoming 5G systems, the full-duplex (FD) communications will be one of the main techniques, which will remove the advantage of using the reciprocal feature in the randomness source common observation. In this paper, we consider the challenge of generating a symmetric secret key between two legitimate parties in the relaying channel with FD capability. We suggest an efficient key extraction protocol that accomplished an acceptable shared secret key rate compared to the direct channel traditional approach. Unlike similar schemes, we provide full statistical analysis for the construction of randomness source from the relaying channel with FD capability. Additionally, we investigate the performance analysis of the suggested key agreement protocol. We also analyze the effect of the curious-but-honest relay and an eavesdropper on the proposed protocol

Physical-Layer Security with Full-Duplex Transceivers and Multiuser Receiver at Eve

Full-duplex communication enables simultaneous transmission from both ends of a communication link, thereby promising significant performance gains. Generally, it has been shown that the throughput and delay gains of full-duplex communication are somewhat limited in realistic network settings, leading researchers to study other possible applications that can accord higher gains. The potential of full-duplex communication in improving the physical-layer security of a communication link is investigated in this contribution. We specifically present a thorough analysis of the achievable ergodic secrecy rate and the secrecy degrees of freedom with full-duplex communication in the presence of a half-duplex eavesdropper node, with both single-user decoding and multi-user decoding capabilities. For the latter case, an eavesdropper with successive interference cancellation and joint decoding capabilities is assumed. Irrespective of the eavesdropper capabilities and channel strengths, the ergodic secrecy rate with full-duplex communication is found to grow linearly with the log of the direct channel signal-to-noise-ratio (SNR) as opposed to the flattened out secrecy rate with conventional half-duplex communication. Consequently, the secrecy degrees of freedom with full-duplex is shown to be two as opposed to that of zero in half-duplex mode