If Beyond-5G(B5G)/6G is to support critical infrastructure worldwide, there must be an effort to jointly integrate low latency and privacy into wireless protocols. This research analyzes new schemes for securing applications at low latency by extending Physical Layer Security (PLS) algorithms to B5G/6G systems. We design protocols that advance a specific form of Physical Layer Security, known as Key-based Physical Layer Security, from the theoretical realm into the practical. One form of a Key-based algorithm obscures information from eavesdroppers by mapping it to cleverly rotated reference signals. For such a scheme, prior work has found that the two-way exchange of completely private information involves six OFDM symbol times, not including synchronization. By developing a protocol that makes the most optimum use of time-frequency resources, we show that it is possible to achieve two-way private exchange and synchronization in only four symbol times - the least latency possible. A significant simulation result indicates that our improved protocol achieves sub-1 ms two-way latency, including re-transmissions. We also illustrate a protocol that shows how Key-based Physical Layer Security can privatize critical PHY layer functions such as cell search. Lastly, additional results show the performance of the PLS algorithm in terms of Key Bit Error Rates and secret key transmission rates.
If Beyond-5G(B5G)/6G is to support critical infrastructure worldwide, there must be an effort to jointly integrate low latency and privacy into wireless protocols. This research analyzes new schemes for securing applications at low latency by extending Physical Layer Security (PLS) algorithms to B5G/6G systems. We design protocols that advance a specific form of Physical Layer Security, known as Key-based Physical Layer Security, from the theoretical realm into the practical. One form of a Key-based algorithm obscures information from eavesdroppers by mapping it to cleverly rotated reference signals. For such a scheme, prior work has found that the two-way exchange of completely private information involves six OFDM symbol times, not including synchronization. By developing a protocol that makes the most optimum use of time-frequency resources, we show that it is possible to achieve two-way private exchange and synchronization in only four symbol times - the least latency possible. A significant simulation result indicates that our improved protocol achieves sub-1 ms two-way latency, including re-transmissions. We also illustrate a protocol that shows how Key-based Physical Layer Security can privatize critical PHY layer functions such as cell search. Lastly, additional results show the performance of the PLS algorithm in terms of Key Bit Error Rates and secret key transmission rates.
Ultra-reliable low latency communication (URLLC) is an innovative service offered by fifth-generation (5G) wireless systems. URLLC enables various mission-critical applications by facilitating reliable and low-latency signal transmission. Apart from reliability and latency, ensuring the security of URLLC data transmission has been a prominent issue in recent years. URLLC uses finite blocklength signals to achieve the stringent reliability and latency requirement which eliminates the possibility of using conventional complex secret key-based cryptographic techniques. In this regard, lightweight security mechanisms like physical layer Security (PLS) have emerged as a powerful alternative to the complex cryptographic security techniques for URLLC by exploiting the randomness of the wireless channel. Therefore, this survey presents a comprehensive and in-depth review of the state-of-the-art PLS enhancements utilized to unleash secure URLLC in 5G and upcoming sixth-generation (6G) wireless networks. Moreover, the survey discusses the impact of system design parameters on the PLS of URLLC. It also incorporates a detailed overview of the recent advancements in ensuring PLS for mission-critical applications, URLLC enabling technologies, and Machine Learning (ML) based intelligent PLS schemes for URLLC. Then, for the first time, the survey introduces the extended service class of URLLC in 6G, i.e., Hyper Reliable Low Latency Communication (HRLLC), and provides an outlook on the future security aspects while identifying various promising new technologies that can provide secure HRLLC in 6G. Finally, the survey identifies several key challenges and highlights interesting future research directions while developing optimal PLS schemes for URLLC in 5G and HRLLC in future 6G wireless networks.
Concern for 5G security is driving interest in additional methods capable of exchanging secure information. This paper introduces a scheme for extending 5G with Physical Layer Security, an emerging Open Systems Interconnect Layer-1 security area that achieves perfect secrecy data transmission. The foundations for a Stochastic Geometry approach to Key based Physical Layer Security are established for 5G Heterogeneous Networks. This work also introduces realistic Time Division Duplex algorithms integrated with 5G-OFDM reference signals that enable the exchange of shared, private information. The resulting Physical Layer Security protocols map random secret key bits to precoders in a codebook through a Precoder Matrix Index. Analysis is presented for Key Bit Error rates under realistic stochastic geometry frameworks in MIMO Rayleigh fading, under various base station densities, interference profiles, and configurations. A Key Bit Error Rate of 1% and 3% for both 1 and 2 bit code books is achieved with a network base station density of 0.01 km-2and 0.1 km-2respectively. The proffered Layer-1 protocols, which operate independently of existing higher layer network and transport layer security, can lead to significantly improved 5G security.
Short-packet communication is a key technology to support two emerging application scenarios in 5G and beyond 5G, massive machine type communication (mMTC) and ultra-reliable low-latency communication (uRLLC), which are introduced to satisfy the broader communication requirements of potential applications such as the Internet of Vehicles and industrial Internet of Things (IoT). The sharp increase in privacy data in various IoT applications has made security issues more prominent. The typical upper-layer encryption mechanism cannot fully address the security challenge considering the resource restriction of IoT terminals. In this article, we investigate secure short-packet communication from the perspective of physical layer security (PLS), which can be regarded as a promising security solution in 6G. Specifically, the state-of-the-art development of fundamental information theory of secure short-packet communications and corresponding performance evaluation criteria in fading channels are summarized. Then we review recent works, which investigate short-packet communication systems in different communication scenarios or with different security strategies from the perspective of PLS. Finally, we give future research directions and challenges.
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.
The increasing demands for Internet of things (IoT) applications and the tremendous increase in the volume of IoT generated data bring novel challenges for the fifth generation (5G) network. Verticals such as e-Health, vehicle to everything (V2X) and unmanned aerial vehicles (UAVs) require solutions that can guarantee low latency, energy efficiency,massive connectivity, and high reliability. In particular, finding strong security mechanisms that satisfy the above is of central importance for bringing the IoT to life. \nIn this regards, employing physical layer security (PLS) methods could be greatly beneficial for IoT networks. While current security solutions rely on computational complexity, PLS is based on information theoretic proofs. By removing the need for computational power, PLS is ideally suited for resource constrained devices. In detail, PLS can ensure security using the inherit randomness already present in the physical channel. Promising schemes from the physical layer include physical unclonable functions (PUFs), which are seen as the hardware fingerprint of a device, and secret key generation (SKG) from wireless fading coefficients, which provide the wireless fingerprint of the communication channel between devices. \nThe present thesis develops several PLS-based techniques that pave the way for a new breed of latency-aware, lightweight, security protocols. In particular, the work proposes: i) a fast multi-factor authentication solution with verified security properties based on PUFs, proximity detection and SKG; ii) an authenticated encryption SKG approach that interweaves data transmission and key generation; and, iii) a set of countermeasures to man-in-the-middle and jamming attacks. Overall, PLS solutions show promising performance, especially in the context of IoT applications, therefore, the advances in this thesis should be considered for beyond-5G networks.
The open nature of radio propagation enables ubiquitous wireless communication. This allows for seamless data transmission. However, unauthorized users may pose a threat to the security of the data being transmitted to authorized users. This gives rise to network vulnerabilities such as hacking, eavesdropping, and jamming of the transmitted information. Physical layer security (PLS) has been identified as one of the promising security approaches to safeguard the transmission from eavesdroppers in a wireless network. It is an alternative to the computationally demanding and complex cryptographic algorithms and techniques. PLS has continually received exponential research interest owing to the possibility of exploiting the characteristics of the wireless channel. One of the main characteristics includes the random nature of the transmission channel. The aforesaid nature makes it possible for confidential and authentic signal transmission between the sender and the receiver in the physical layer. We start by introducing the basic theories of PLS, including the wiretap channel, information-theoretic security, and a brief discussion of the cryptography security technique. Furthermore, an overview of multiple-input multiple-output (MIMO) communication is provided. The main focus of our review is based on the existing key-less PLS optimization techniques, their limitations, and challenges. The paper also looks into the promising key research areas in addressing these shortfalls. Lastly, a comprehensive overview of some of the recent PLS research in 5G and 6G technologies of wireless communication networks is provided.