This paper discusses the design of two Physical Layer Security (PLS) techniques in GNU Radio. PLS is a classification of security methods that take advantage of physical properties in the waveform or channel to secure communication. These schemes can be used to directly obfuscate the signal from eavesdroppers, or even generate secret keys for traditional encryption methods. Over the past decade, advancements in Multi Input Multi Output (MIMO) systems have expanded the potential capabilities of PLS while the development of technologies such as the Internet of Things (IoT) has provided new applications. As a result, this field has become heavily researched, but is still lacking implementation. The design work covered here attempts to alleviate this issue by providing a platform for Over-The-Air (OTA) experimentation.
This paper discusses the design of two Physical Layer Security (PLS) techniques in GNU Radio. PLS is a classification of security methods that take advantage of physical properties in the waveform or channel to secure communication. These schemes can be used to directly obfuscate the signal from eavesdroppers, or even generate secret keys for traditional encryption methods. Over the past decade, advancements in Multi Input Multi Output (MIMO) systems have expanded the potential capabilities of PLS while the development of technologies such as the Internet of Things (IoT) has provided new applications. As a result, this field has become heavily researched, but is still lacking implementation. The design work covered here attempts to alleviate this issue by providing a platform for Over-The-Air (OTA) experimentation.
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) leverages physical characteristics of wireless channels to allow secure data transfer in wireless communications. While PLS has received considerable research, its practical implementation is still evolving. To address this gap, this work designs and implements a keyless PLS-based communication scheme using three USRP devices in an over-the-air environment in which a multi-antenna transmitter infuses an artificial Gaussian noise source to the nullspace of an intended receiver in order to obscure the received signal of an eavesdropper. The design is applicable to high-order quadrature amplitude modulation (QAM) constellations, which is suitable for high-spectral efficiency wireless communication systems. Our measurement results fully demonstrate the confidentiality achieved by the proposed PLS implementation.
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.
Massive Multiple-Input Multiple-Output (MIMO) has become a crucial enabling technology for 5G and beyond, providing previously unheard-of increases in energy and spectrum efficiency. It is still difficult to guarantee secure communication in these systems, particularly when it comes to passive eavesdroppers whose base station is unaware of their channel state information. By taking advantage of the inherent randomness of wireless channels, Physical Layer Security (PLS) offers a promising paradigm; however, its efficacy in massive MIMO is heavily reliant on resource allocation and transmission strategies. In this work, the performance of secure transmission schemes, such as Maximum Ratio Transmission (MRT), Zero-Forcing (ZF), and Artificial Noise (AN)-aided beamforming, is examined when passive eavesdroppers are present. This work will use extensive Monte Carlo simulations to assess important performance metrics such as energy efficiency, secrecy outage probability, and secrecy sum rate under different system parameters (e.g., number of antennas, Signal-to-Noise Ratio (SNR), power allocation). The results aim to provide comparative insight into the strengths and limitations of different PLS strategies and to highlight open research directions to design scalable, energy-efficient, and robust secure transmission techniques in future 6G networks.
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.
With the uninterrupted revolution of communications technologies and the great-leap-forward development of emerging applications, the ubiquitous deployment of Internet of Things (IoT) is imperative to accommodate constantly growing user demands and market scales. Communication security is critically important for the operations of IoT. Among the communication security provisioning techniques, physical layer security (PLS), which can provide unbreakable, provable, and quantifiable secrecy from an information-theoretical point of view, has drawn considerable attention from both the academia and the industries. However, the unique features of IoT, such as low-cost, wide-range coverage, massive connection, and diversified services, impose great challenges for the PLS protocol design in IoT. In this article, we present a comprehensive review of the PLS techniques toward IoT applications. The basic principle of PLS is first briefly introduced, followed by the survey of the existing PLS techniques. Afterwards, the characteristics of IoT are identified, based on which the challenges faced by PLS protocol design are summarized. Then, three newly-proposed PLS solutions are highlighted, which match the features of IoT well and are expected to be applied in the near future. Finally, we conclude the paper and point out some further research directions.