Secure Transmission Design for Cooperative NOMA in the Presence of Internal Eavesdropping

Abstract

The application of successive interference cancellation (SIC) introduces critical security risks to cooperative non-orthogonal multiple access (NOMA) systems in the presence of untrustworthy network nodes, referred to as internal eavesdroppers. To address this potential security and reliability flaw, by assuming all users are untrusted, this letter investigates the effective secrecy throughput (EST) for a cooperative NOMA system, where a near user serves as an amplify-and-forward relay to help forward the information of a far user. Considering the inverse power allocation and SIC decoding order, a novel jamming strategy is proposed to enhance the security performance of the far user. Gauss-Chebyshev approximations of ESTs over Nakagami-m channels are derived. Asymptotic EST expressions are proposed to provide further insights. Numerical results demonstrate that the proposed jamming strategy and the inverse power allocation and SIC decoding order are both essential for achieving positive secrecy rates for both users.

User-pairing in NOMA Uplink networks under Secrecy Constraints

“…In the downlink, the use of successive interference cancellation (SIC) at the receiver makes it possible for strong users to behave as internal eavesdroppers to weak users while at the same time the air interface makes transmissions vulnerable to eavesdropping outside the network [3]. Multiple physical layer security approaches have been investigated in the past, including the injection of artificial noise [4]. An alternative to artificial noise injection can be provided by considering full-duplex (FD) systems, to ensure that a certain level of interference is guaranteed.…”

“…An alternative to artificial noise injection can be provided by considering full-duplex (FD) systems, to ensure that a certain level of interference is guaranteed. The authors in [5]- [7] investigated the security performance of cooperative NOMA with external eavesdropping, while [4] considers the presence of internal eavesdropping. Furthermore, the secure transmission for noncooperative NOMA with internal and external eavesdropping is studied in [8], [9].…”

Secrecy Performance of RIS Aided NOMA Networks

“…Triggered by this, the authors of [20] researched the secrecy performance of unified NOMA framework by taking into account stochastic geometry under external and internal eavesdropping scenarios. Additionally, the secure communications of cooperative NOMA networks were revealed in [21], where the secrecy throughput was improved greatly.…”