Secure Relay Selection for Two-Way Untrusted Relaying Networks

Van Phu Tuan, Hyung Yun Kong

Faezeh Sharifi, Soroush Akhlaghi

Tantan Zhao, Guobing Li, Gangming Lyu +1 more

Abstract In this paper, the selective cooperation with untrusted relays is studied for wireless multipair two‐way relay networks. We first investigate the feasibility of secure transmission in the presence of cooperative but untrusted relays and then formulate a general optimization problem of secrecy sum‐rate maximization under the constraints of relay selection. By decomposing the original problem into solvable subproblems, we develop a low‐complexity greedy algorithm for selective cooperation, in which the untrusted relays are selected as cooperators or the potential eavesdroppers according to the overall contributions to the secrecy sum rate. Simulation results reveal that the proposed greedy algorithm for selective cooperation with untrusted relays achieves performance gain both in instantaneous and average secrecy sum rate and that the algorithm can converge quickly with the iterations.

Jing Huang, Arnold Lee Swindlehurst

We investigate a relay network where the source and destination select one relay out of a group of untrusted relay nodes to establish a reliable and confidential connection. We assume there is no direct link between them, and the users have to employ an untrusted relay while simultaneously protecting the confidential data from it. We study joint transmit design and node selection strategies for both one-way relaying with the help of cooperative jamming from the destination, and two-way relaying. We first derive optimal algorithms through numerical methods for secrecy rate maximization, and then we propose closed-form suboptimal solutions with reduced complexity. Simulation results show that unlike the conventional relay channels, when untrusted relays are used, one-way relaying with cooperative jamming is more efficient than the two-way relaying scheme in terms of secrecy rate.

Fu Jiang, Chaoliang Zhu, Jun Peng +3 more

Huynh Van Hoa, Chan Dai Truyen Thai, Nguyen Thi Yen Linh +1 more

In this paper, we consider a two-way relay secure communications scheme where the two sources can only communicate through untrusted amplify-and-forward relays in the presence of jammers. We propose several schemes to optimize the secure sum-rate of the network including the optimal exhaustive search scheme (Best R) and other sub-optimal schemes including selecting the relay with the maximum of the minimum channel gain to two sources (MaxMin Gain) and a random relay (Random R) considering two modes of uniform and different jamming powers. Furthermore, to investigate the effect of number relays, we also analyzed secrecy rates based on three different schemes and two modes. Finally, the simulation results verify the properties and efficiency of the proposed scheme.