Physical Layer Security for RF-Based Massive IoT

In the 6G era, physical layer security (PLS) can be foreseen as a promising solution to enhance the security of future massive Internet of Things (IoT) applications relying on RF-based IoT systems as PLS takes advantage of the unique characteristics of the wireless channel and the transceiver hardware to enable lightweight security schemes for the resource-constrained IoT systems, ensuring IoT node authentication, confidentiality of the exchanged data, and malicious node detection. The target of the IoT node authentication is that each node should identify and authenticate the other communicating entity, and data confidentiality ensures that exchanged data are not disclosed to unauthorized entities. In addition, malicious node detection aims to detect malicious activity within the network and identify the perpetrator. The objective of this chapter is to introduce the reader to the concept of PLS and provide a high-level overview of the wide array of physical layer-based security approaches that have been proposed in the recent literature to achieve node authentication, data confidentiality, and malicious node identification, and are suitable for integration into massive IoT networks.