Detection and Localization of Stealthy Cyberattacks in Cyber-Physical Discrete Event Systems

The widespread use of cyber-physical systems not only brings new opportunities with it but also introduces the risk of cyberattacks on the system. One of the most dangerous and sophisticated types of attacks are the stealthy attacks that can hide their influence and are not detectable by conventional anomaly detection schemes. In this article, a detection method for the replay attack and the covert attack on discrete event systems is proposed. Unexpected behavior is introduced into the transmitted signals by the integration of permutation matrices into the sensor and actuator channels. The permutation disrupts the stealthiness of an attacker and allows the detection of cyberattacks. Moreover, an attack localization scheme is proposed, which allows us to determine which signals are attacked in case that the attacker only attacks a subset of communication channels and not the whole system.