Physical-Layer Security and Reliability Challenges for Industrial Wireless Sensor Networks

The open nature of radio propagation makes wireless transmissions exposed to unauthorized users and become vulnerable to both the jamming and eavesdropping attacks. In industrial environments, wireless transmissions are also adversely affected by the presence of large-bodied obstructing machinery, metallic friction-induced impairments, and equipment noise. This may result in the failure of wireless transmissions and thus wastes the precious energy resources for industrial wireless sensor networks (IWSNs). This paper is motivated to present a review on the challenges and solutions of improving the physical-layer security and reliability for IWSNs. We first discuss some wireless reliability enhancement techniques for mitigating the background interference, path loss, multipath fading, and link failure. Then, we provide an overview of wireless jamming and eavesdropping attacks along with their countermeasures, where a jammer attempts to emit an interfering radio signal for disrupting the desired communications between a wireless sensor and its sink, while an eavesdropper intends to tap the confidential sensor-sink transmissions. Additionally, we evaluate the tradeoff between the security and reliability, called security-reliability tradeoff, in the context of wireless sensor-sink transmissions. Finally, we discuss a range of open challenges and future trends for IWSNs, including the energy-efficient security and reliability designs, joint jamming-and-eavesdropping defense mechanisms, as well as the energy harvesting for IWSNs.