Constrained Colluding Eavesdroppers

Cees J. A. Jansen

Mahtab Mirmohseni, Panos Papadimitratos

We study the secrecy capacity in the vicinity of colluding eavesdroppers. Contrary to the perfect collusion assumption in previous works, our new information-theoretic model considers constraints in collusion. We derive the achievable secure rates (lower bounds on the perfect secrecy capacity), both for the discrete memoryless and Gaussian channels. We also compare the proposed rates to the non-colluding and perfect colluding cases.

Nam‐Phong Nguyen, Chinmoy Kundu, Van‐Dinh Nguyen +2 more

In this paper, we investigate the secure communication of cognitive full-duplex relay networks in the presence of multiple eavesdroppers and multiple primary receivers. In the considered network, multiple full-duplex relays are deployed to transfer information in the secondary network, under the malicious attempts of non- colluding/colluding eavesdroppers. Meanwhile, the transmit powers of secondary transmitters are constrained by the quality-of-service of the primary network. The optimal relay selection scheme is proposed to enhance the secrecy performance of the considered system. We study the secrecy performance by providing the exact closed- form and asymptotic expressions of the proposed system secrecy outage probability. We have demonstrated that increasing the number of full- duplex relays can improve the security performance. At the illegitimate side, using colluding eavesdroppers and increasing the number of eavesdroppers put information confidentiality at a greater risk. Besides, the transmit power and the desired outage probability of the primary network have great influences on the secrecy outage probability of the secondary network.

Linda Hansen, Ricardo J. Matos, Giuliano Matessi +1 more

Tao Xu, Xuanli Wu, Xiaosen Xue +1 more

The full-space capability of the reconfigurable intelligent surface (RIS) provides an intelligent radio environment for information transmissions. This paper investigates the RIS-assisted secure transmissions in the presence of multiple eavesdroppers (Eves), where the colluding and the non-colluding behaviors of Eves are considered. We first propose a tractable Gamma distribution to characterize the distributions of the signal-to-noise ratio (SNR) under the Rayleigh, the Rice and the Nakagami-m channels. Then we derive the theoretical expressions of the average security capacity (ASC) for colluding and non-colluding eavesdroppers. Besides, the asymptotic expressions of the ASC are also obtained when the SNRs are large in practical scenarios. The simulation results demonstrate that the RIS is capable of reducing the negative impact of the increase in the number of eavesdroppers on the security performance by deploying more RIS elements in both colluding and non-colluding eavesdroppers.