Smart and Secure Wireless Communications via Reflecting Intelligent Surfaces: A Short Survey

Abstract

With the emergence of the internet of things (IoT) technology, wireless connectivity should be more ubiquitous than ever. In fact, the availability of wireless connection everywhere comes with security threats that, unfortunately, cannot be handled by conventional cryptographic solutions alone, especially in heterogeneous and decentralized future wireless networks. In general, physical layer security (PLS) helps in bridging this gap by taking advantage of the fading propagation channel. Moreover, the adoption of reconfigurable intelligent surfaces (RIS) in wireless networks makes the PLS techniques more efficient by involving the channel into the design loop. In this paper, we conduct a comprehensive literature review on the RIS-assisted PLS for future wireless communications. We start by introducing the basic concepts of RISs and their different applications in wireless communication networks and the most common PLS performance metrics. Then, we focus on the review and classification of RIS-assisted PLS applications, exhibiting multiple scenarios, system models, objectives, and methodologies. In fact, most of the works in this field formulate an optimization problem to maximize the secrecy rate (SR) or secrecy capacity (SC) at a legitimate user by jointly optimizing the beamformer at the transmitter and the RIS's coefficients, while the differences are in the adopted methodology to optimally/sub-optimally approach the solution. We finalize this survey by presenting some insightful recommendations and suggesting open problems for future research extensions.

Towards intelligent reflecting surface empowered 6G terahertz communications: A survey

“…Although THz communications possess much better security performance than microwave and mmWave communications to a certain extent, improving the security level of the THz communication system is still a pressing problem [45]. Since THz communications pro- vide ultra-high data transmission, so tremendous private data can be grabbed by the eavesdropper during a short time frame [46]. Based on this, the secret data leakage problem needs to be investigated thoroughly for the communication scenarios with high data rates.…”

Reconfigurable Intelligent Surface Aided Multi-User Communications: State-of-the-Art Techniques and Open Issues

“…Security and privacy [80], [81] PLS concepts, applications, and open research problems. [82] Security in energy harvesting networks.…”

“…As a result, there is now more research interest in the development of secure data transmission based on the physical layer of the wireless channel. Mathematically, the integration of RISs with PLS brings about new communication system models and optimization techniques beneficial to enhancing Secrecy Rate Maximization (SRM), secrecy capacity, and SOP in wireless communications without relying on encryption techniques [81], [82]. We next briefly discuss the RISenabled state-of-the-art solutions proposed by several authors along these lines, and Table 7 provides a summary of the main system setup, key contributions and proposed technical solutions.…”

Secrecy Performance Analysis for Reconfigurable Intelligent Surface aided NOMA Network

“…Considering the broadcast nature of wireless transmission, the issue of physical layer security (PLS) attracted widespread interests. Although rigorous efforts have been done in PLS of wireless communications, overall progress has been relatively slow [14]. However, the emergence of RIS technology provides a new solution for PLS problem.…”