Cybersecurity of Discrete Event Systems

This book describes analysis and control against smart cyberattacks in discrete event systems (DES). This is the first technical DES book to provide a thorough introduction to smart cyberattacks on supervisory control systems modelled by regular languages or finite-state automata and possible resilient defence methods against smart cyberattacks. "Smart attacks" cannot be detected by the supervisor until an irreversible process toward ensured damage occurs. An attack may be conducted either in the observation channel (i.e., the supervisor's input of the supervisor) or in the command channel (i.e., the supervisor's output) or both simultaneously. Therefore, defence strategies against these attacks are urgently needed. Rong Su provides a comprehensive overview of the latest theories and includes empirical examples to illustrate concepts and methods. By centering on what information is available and how such information is used, the readers are provided with methods to evaluate the cyber vulnerability of a given system and design a resilient supervisor against relevant smart attacks. This book comprises two sections. Firstly, Su introduces the required concepts and techniques related to DES and supervisory control. Then he introduces different types of smart attacks that intercept and manipulate information in sensor and command channels in a standard closed-loop control system. Secondly, he presents resilient defence strategies against relevant types of attacks. By focusing on a conceptual introduction and systematic analysis, this book provides a solid theoretical foundation for future exploration by researchers and graduate students who are interested in cybersecurity research, not necessarily limited to those in the DES community. To illustrate the practical relevance of this research, realistic examples are used throughout this book. Readers are recommended to have a background in formal language theory.

Rong Su, PhD, is a Professor at the School of Electrical and Electronic Engineering and Director of the Centre for System Intelligence and Efficiency at Nanyang Technological University. He earned a BE degree at the University of Science and Technology of China and an MAS degree and a PhD degree at the University of Toronto. Dr. Su is a senior member of IEEE and an associate editor for IEEE Transactions on Cybernetics, Automatica (IFAC), Journal of Discrete Event Dynamic Systems and Journal of Control and Decision. Dr. Su is prolifically published and has received several best paper awards, such as the 2021 Hsue-shen Tsien Paper Award from the IEEE/CAA Journal of Automatica Sinica and the Best Paper Award at the 15th International Conference on Advanced Systems in Public Transport (CASPT2022). He is an IEEE Distinguished Lecturer for the IEEE Robotics and Automation Society.

1. Introduction to Cybersecurity in Discrete Event Systems. Part I: Modeling and Synthesis of Smart Attacks. 2. Smart Sensor Attacks. 3. Smart Sensor-Actuator Attacks. 4. Smart Attacks with Unknown Supervisor. Part II: Modeling and Synthesis of Resilient Supervisors. 5. Resilient Supervisory Control against Smart Sensor Attacks. 6. System Vulnerability Analysis via Attack Model Reduction. 7. Supervisor Obfuscation against Smart Actuator Attacks.