Visible to the public Finite energy and bounded attacks on control system sensor signals

TitleFinite energy and bounded attacks on control system sensor signals
Publication TypeConference Paper
Year of Publication2014
AuthorsDjouadi, S.M., Melin, A.M., Ferragut, E.M., Laska, J.A., Jin Dong
Conference NameAmerican Control Conference (ACC), 2014
Date PublishedJune
ISBN Number978-1-4799-3274-0
Keywordsactuator signal attacks, attack free systems, bounded attacks, closed loop systems, closed-loop systems, Computer crime, computer network reliability, computer network security, Control applications, control system networks, control system protection, control system reliability, control system sensor signals, Cost function, cost functions maximization, CPS protecting, critical industrial controls systems, cyber-attacks, cyber-physical systems protection, distributed LQ controllers, Eigenvalues and eigenfunctions, Emerging control theory, enterprise level networks, error signals, Fault-tolerant systems, finite energy, Generators, hardware failures, information security techniques, linear quadratic control, linear quadratic Gaussian control, networks security, observer-based controlled systems, power generation network, sensor signal attacks, Sensors, software failures, threat surface, Vectors

Control system networks are increasingly being connected to enterprise level networks. These connections leave critical industrial controls systems vulnerable to cyber-attacks. Most of the effort in protecting these cyber-physical systems (CPS) from attacks has been in securing the networks using information security techniques. Effort has also been applied to increasing the protection and reliability of the control system against random hardware and software failures. However, the inability of information security techniques to protect against all intrusions means that the control system must be resilient to various signal attacks for which new analysis methods need to be developed. In this paper, sensor signal attacks are analyzed for observer-based controlled systems. The threat surface for sensor signal attacks is subdivided into denial of service, finite energy, and bounded attacks. In particular, the error signals between states of attack free systems and systems subject to these attacks are quantified. Optimal sensor and actuator signal attacks for the finite and infinite horizon linear quadratic (LQ) control in terms of maximizing the corresponding cost functions are computed. The closed-loop systems under optimal signal attacks are provided. Finally, an illustrative numerical example using a power generation network is provided together with distributed LQ controllers.

Citation Key6859001