Resilient control in the presence of DoS attack: Switched system approach

This paper studies the switched resilient control of the Cyber-Physical Systems (CPSs) under Denial-of-Service (DoS) attack. We interpret the term ‘resilience’ as the ability to be both robust to the external disturbances in the physical layer, and defending against DoS attacks in the cyber layer. A hybrid-theoretical framework is proposed which is comprised of a physical control subsystem, a cyber security subsystem, and an interface which integrates the control design with the security configuration. Within this framework, the controller will switch in accordance with the competing result of the cyber attacker and defender. Our approach highlights the interaction between the physical control layer and cyber security layer and achieves the goal of coupled design. Some algorithms are provided to obtain the so-called joint defense strategies. Finally, the proposed method is applied to the voltage regulation of the Uninterrupted Power System (UPS).