Sensor and Actuator Attacks in Discrete Event Systems

In supervised discrete event systems under attack, the goal of the supervisor, who has a partial observation of the system evolution, is to prevent the system from reaching a set of unsafe states. An attacker may act in two different ways: it can corrupt the observation of the supervisor by editing the sensor readings, and it can enable events that have been disabled by the supervisor. This is done with the aim of leading the plant to an unsafe state. A special automaton, called attack structure is constructed as the parallel composition of two special structures: an attacker observer and a supervisor under attack. Such an automaton can be used by the attacker to select proper actions (if any) to lead the plant to reach the unsafe state. Copyright (C) 2022 The Authors.