Security has emerged as one of the critical requirements of future wireless networks. Unlike traditional cryptography-based security, physical layer security (PLS) tends to exploit 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. Due to the limited capability of the legacy wireless networks, only a few channel features could be effectively exploited for PLS. Future wireless networks are envisioned to feature advanced transceiver technologies, signal processing techniques, channel control, and sensing capabilities which will allow them to easily access and extract additional channel features that can be readily exploited for PLS. The novel use cases to be accommodated in future networks are also found to experience some peculiar channel characteristics which enrich the list of channel features that can be exploited for PLS. This article, thus, tends to highlight the opportunities and potential challenges of these new channel features from the PLS perspective. In the course of the article, the assessment of important qualities while selecting a certain channel feature for the PLS application is discussed. The importance of the channel control concept and sensing technologies for PLS is highlighted. Finally, the article discusses the challenges and vulnerabilities of the channel-based PLS concept from which future research directions are derived.
Security has emerged as one of the critical requirements of future wireless networks. Unlike traditional cryptography-based security, physical layer security (PLS) tends to exploit 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. Due to the limited capability of the legacy wireless networks, only a few channel features could be effectively exploited for PLS. Future wireless networks are envisioned to feature advanced transceiver technologies, signal processing techniques, channel control, and sensing capabilities which will allow them to easily access and extract additional channel features that can be readily exploited for PLS. The novel use cases to be accommodated in future networks are also found to experience some peculiar channel characteristics which enrich the list of channel features that can be exploited for PLS. This article, thus, tends to highlight the opportunities and potential challenges of these new channel features from the PLS perspective. In the course of the article, the assessment of important qualities while selecting a certain channel feature for the PLS application is discussed. The importance of the channel control concept and sensing technologies for PLS is highlighted. Finally, the article discusses the challenges and vulnerabilities of the channel-based PLS concept from which future research directions are derived.
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.
One of the critical requirements of the future wireless networks is the provision of secure communication against wide range of attacks. Contrary to the conventional cryptography-based security, physical layer security (PLS), in the broadest sense, intends to exploit different features of the wireless channel to secure not only the information being communicated but the whole communication process from myriad types of attacks. Future generations of the wireless networks will be built on various new technologies such as massive multiple input multiple output (mMIMO), reconfigurable intelligent surfaces (RIS), and sensing, and are expected to accommodate some newly emerging use-cases that never existed in the legacy networks. Both, the new technologies and the use-cases are accompanied with some new and unique channel characteristics which can be leveraged by the channel-based PLS concept. This chapter explores these newly revealed channel features to highlight their potential advantages and challenges if exploited for PLS. Specifically, the chapter provides a ground work on the critical qualities that define the eligibility of a certain channel feature for the PLS application. Afterward, channel features unique to different scenarios (such as high mobility in vehicle-to-vehicle and high speed train communication) or technologies (such as mMIMO and communication at higher frequency bands) in 5G and beyond networks are discussed form the PLS perspective. The chapter also touches upon the evolving class of security attack that intend to disrupt the channel-based PLS concept by attacking the channel characteristics/features rather than the communication itself. The chapter is then concluded by summarizing some possible research directions for the channel-based PLS concept.
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.
Abstract Due to the open nature of wireless communication systems, the data transmission over these networks are vulnerable to malicious attack. To safeguard the transmitted data, physical layer security (PLS) has been emerged as a promising technique because of its unique feature of utilizing randomness of the wireless channel to secure the information. The preeminent idea of utilizing the channel imperfections such as fading and noise into the security providing resource is the basic approach behind PLS. For exploiting the randomness of the propagation medium, the analysis of the secrecy performance over the fading channel is of utmost importance. With the explanation of basic theory and technology, this paper presents an elaborated survey on the PLS research over the fading channels. To exploit the performance gains, we discuss the optimization approaches in different network design problems, for example, secrecy rate maximization, power minimization, and secure energy efficiency problems. We present a comparative study of the expressions of various performance metrics of the PLS along with classification depending upon the channel state information of the eavesdropper. The application and challenges of the PLS in the emerging wireless technologies are also reviewed and discussed. This paper incorporates almost all the aspects of PLS implemented over the fading channels. Furthermore, the paper is concluded with open research directions for the PLS system in various fields that can be explored to design a flexible and robust security system to satisfy the security requirements of the next‐generation networks.
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.
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.