A Review on Physical Layer Security Techniques for 5G

José David Vega Sánchez, Luis Felipe Urquiza-Aguiar, Martha Cecilia Paredes Paredes +1 more

Jehad M. Hamamreh

Parmila Devi, Manoranjan Rai Bharti, Dikshant Gautam

Li Sun, Qinghe Du

5G network is expected to support massive user connections and exponentially increasing wireless services, which makes network security unprecedentedly important. Unlike traditional security-guaranteeing techniques which rely heavily on cryptographic approaches at upper layers of the protocol stack, physical-layer security (PLS) solutions fully take advantages of the characteristics of wireless channels to degrade the received signal qualities at the malicious users, and realize keyless secure transmission via signal design and signal processing techniques. PLS avoids the difficulties in the distribution and management of secret keys, and provides flexible security levels through adaptive transmission protocol design. Moreover, PLS techniques match the features of 5G networks well. Therefore, the application of PLS to 5G networks is a promising solution to address the security threats. This article presents a comprehensive review of the state-of-the-art PLS techniques, and discusses their applications in 5G networks. We first summarize the principle and advantages of PLS techniques, and point out the reasons why PLS is suitable for 5G networks. Then, we review the existing PLS methods in literature, and highlight several PLS solutions that are expected to be applied in 5G networks. Finally, we conclude this article and figure out some further research directions.

Mulugeta Kassaw Tefera, Zengwang Jin, Shengbing Zhang

With the proliferation of 5G mobile networks within next-generation wireless communication, the design and optimization of 5G networks are progressing in the direction of improving the physical layer security (PLS) paradigm. This phenomenon is due to the fact that traditional methods for the network optimization of PLS fail to adapt new features, technologies, and resource management to diversified demand applications. To improve these methods, future 5G and beyond 5G (B5G) networks will need to rely on new enabling technologies. Therefore, approaches for PLS design and optimization that are based on artificial intelligence (AI) and machine learning (ML) have been corroborated to outperform traditional security technologies. This will allow future 5G networks to be more intelligent and robust in order to significantly improve the performance of system design over traditional security methods. With the objective of advancing future PLS research, this review paper presents an elaborate discussion on the design and optimization approaches of wireless PLS techniques. In particular, we focus on both signal processing and information-theoretic security approaches to investigate the optimization techniques and system designs of PLS strategies. The review begins with the fundamental concepts that are associated with PLS, including a discussion on conventional cryptographic techniques and wiretap channel models. We then move on to discuss the performance metrics and basic optimization schemes that are typically adopted in PLS design strategies. The research directions for secure system designs and optimization problems are then reviewed in terms of signal processing, resource allocation and node/antenna selection. Thereafter, the applications of AI and ML technologies in the optimization and design of PLS systems are discussed. In this context, the ML- and AI-based solutions that pertain to end-to-end physical layer joint optimization, secure resource allocation and signal processing methods are presented. We finally conclude with discussions on future trends and technical challenges that are related to the topics of PLS system design and the benefits of AI technologies.

Shuruq Khalid Abdulredha

The evolution from 5G to 6G wireless networks is driving a fundamental transformation in encryption technologies. While 5G networks primarily rely on advanced classical cryptography, including AES, ECC, and RSA, emerging applications such as IoT, e-healthcare, and ultra-reliable low-latency communications demand lightweight, hybrid, and context-aware security schemes. The advent of quantum computing poses significant threats to classical cryptosystems, motivating the integration of quantum-resistant security techniques, including post-quantum cryptography (PQC), quantum key distribution (QKD), and physical layer security (PLS) in 6G networks. This review synthesizes recent research on classical, hybrid, and quantum-resistant security techniques, highlighting the shift toward multi-layered and adaptive security frameworks. A comparative analysis of PLS in 5G and 6G illustrates its transition from a complementary role to a core security mechanism, especially in ultra-low-latency, massive connectivity, and heterogeneous environments. Finally, open research questions and standardization challenges are discussed, emphasizing the need for scalable, energy-efficient, and interoperable security solutions for next-generation wireless networks.