Physical layer security (PLS) is emerging as an attractive security paradigm to complement or even replace complex cryptography. Although information-theoretical transmission optimization and physical-layer key generation have been thoroughly researched, there still exist many critical issues to be tackled before PLS is extensively applied. In this article, we investigate the prospect for exploiting artificial intelligent (AI) and edge computing (EC) to facilitate the practical application of PLS. First, two outstanding challenges facing PLS designers are identified by analyzing the fundamental assumptions regarding eavesdroppers and wireless channels. Accordingly, two enhancement schemes are designed by reaping the benefits offered by AI and EC. Specifically, a novel secure resource management framework is developed to enhance the adaptability of an optimization-based PLS paradigm, and a robust physical-layer key generation method is designed to cope with reciprocity failure. Finally, we discuss a coordinated defense architecture with multi-layer, multi-domain, and multi-dimension, which is expected to exploit the compatibility and complementarity of the existing PLS methods.
Physical layer security (PLS) is emerging as an attractive security paradigm to complement or even replace complex cryptography. Although information-theoretical transmission optimization and physical-layer key generation have been thoroughly researched, there still exist many critical issues to be tackled before PLS is extensively applied. In this article, we investigate the prospect for exploiting artificial intelligent (AI) and edge computing (EC) to facilitate the practical application of PLS. First, two outstanding challenges facing PLS designers are identified by analyzing the fundamental assumptions regarding eavesdroppers and wireless channels. Accordingly, two enhancement schemes are designed by reaping the benefits offered by AI and EC. Specifically, a novel secure resource management framework is developed to enhance the adaptability of an optimization-based PLS paradigm, and a robust physical-layer key generation method is designed to cope with reciprocity failure. Finally, we discuss a coordinated defense architecture with multi-layer, multi-domain, and multi-dimension, which is expected to exploit the compatibility and complementarity of the existing PLS methods.
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.
Physical layer security (PLS) has emerged as a new concept and powerful alternative that can complement and may even replace encryption-based approaches, which entail many hurdles and practical problems for future wireless systems. The basic idea of PLS is to exploit the characteristics of the wireless channel and its impairments including noise, fading, interference, dispersion, diversity, etc. in order to ensure the ability of the intended user to successfully perform data decoding while preventing eavesdroppers from doing so. Thus, the main design goal of PLS is to increase the performance difference between the link of the legitimate receiver and that of the eavesdropper by using well-designed transmission schemes. In this survey, we propose a conceptual, generic, and expandable framework for classifying the existing PLS techniques against wireless passive eavesdropping. In this flexible framework, the security techniques that we comprehensively review in this treatise are divided into two primary approaches: signal-to-interference-plus-noise ratio-based approach and complexity-based approach. The first approach is classified into three major categories: first, secrecy channel codes-based schemes; second, security techniques based on channel adaptation; third, schemes based on injecting interfering artificial (noise/jamming) signals along with the transmitted information signals. The second approach (complexity-based), which is associated with the mechanisms of extracting secret sequences from the shared channel, is classified into two main categories based on which layer the secret sequence obtained by channel quantization is applied on. The techniques belonging to each one of these categories are divided and classified into three main signal domains: time, frequency and space. For each one of these domains, several examples are given and illustrated along with the review of the state-of-the-art security advances in each domain. Moreover, the advantages and disadvantages of each approach alongside the lessons learned from existing research works are stated and discussed. The recent applications of PLS techniques to different emerging communication systems such as visible light communication, body area network, power line communication, Internet of Things, smart grid, mm-Wave, cognitive radio, vehicular ad-hoc network, unmanned aerial vehicle, ultra-wideband, device-to-device, radio-frequency identification, index modulation, and 5G non-orthogonal multiple access based-systems, are also reviewed and discussed. The paper is concluded with recommendations and future research directions for designing robust, efficient and strong security methods for current and future wireless systems.
Physical layer security (PLS) has become the kernel concept for ensuring wireless network security. The main goal of this treatise is to provide a systematic classification of key less schemes. We have classified key less PLS into code, channel adaptation and artificial noise (AN) based approaches and carried out a survey of the diverse schemes employed in literature for key less approach. Further, we have provided the advantages, observations and future directions for each of the techniques. Industry 4.0 revolution with the Internet of Things (IoT) is going to rule the next wireless era with its promising smart home, smart health care, smart retail to name a few. Therefore, we have provided a discussion on the application of key less PLS in IoT. Further, we also discuss about two emerging areas that can be employed for enhancing PLS such as Intelligent Reflecting Surface (IRS) and Artificial Intelligence (AI). We have also provided some of the existing security challenges in the IoT application scenario. We have also presented the open research challenges and future directions in the area of key less PLS.
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.
Physical layer security (PLS) has emerged as a promising approach to enhance the security of wireless communication systems. This paper provides a comprehensive review of PLS, including its basic concepts, key techniques, and recent developments. We begin by introducing the basic principles of PLS, including the concept of secrecy capacity and the key assumptions underlying PLS. We then discuss various techniques that have been proposed to enhance PLS, such as artificial noise, cooperative jamming, and beamforming. Next, we review recent research on PLS in different scenarios, including multi-user systems, cognitive radio networks, and wireless sensor networks. Finally, we conclude by discussing future research directions and open challenges in PLS.
Security has emerged as one of the critical requirements in future wireless networks. Unlike traditional cryptography-based security, physical layer security (PLS) exploits various features of the random wireless channel to secure not only the information being communicated but the whole communication process from any type of attack. Future wireless networks are envisioned to feature new technologies such as re-configurable intelligent surfaces, massive multiple input multiple output, and sensing, to accommodate the emerging use-cases. Both, the new technologies and the new use-cases have been found to enrich the channel characteristics by unveiling some new channel features which can be readily exploited to facilitate PLS. This article surveys these new channel features to reveal their potential for PLS implementation. In the course of the article, the assessments of important qualities while selecting a certain channel feature for the PLS application are discussed. The importance of the channel control concept and sensing technologies that facilitate the accessibility of certain channel features are highlighted from the PLS perspective. Security attacks aimed at channel characteristics, rather than the communication itself, in order to disrupt PLS implementations are also discussed. Finally, the article summarizes the possible research direction for channel-based PLS.