Safe and Secure Wireless Networked Control Systems

Wireless technology has gained much interest in industrial automation due to its flexibility, mobility, ease of installation, and lower cost. Wireless systems, in general, require additional and different engineering and maintenance tasks, for example cryptographic key management for security. The pace of application in process control has been impeded, however, by concern about the risks involved in incorporating wireless paths in feedback loops and making the accommodations necessary for reliable control. The issue is that there are conflicts between maintaining control loop performance and the usual objectives in managing a wireless sensor network. In this paper, we take a holistic approach that addresses safety, reliability and security in two primary aspects: communication and control; thus we hope to contribute a more complete roadmap for developing safe and secure wireless networked control systems. This proposed framework represents a synthesis of two formerly separate bodies of research, one primarily focussed on communication requirements for safety and security and the other on safe and reliable controls.