A Decoupled Feedback Structure for Covertly Appropriating Networked Control Systems

The use of communication networks for the transmission of control system signals (measurements and actuation) is becoming more widespread. If the communication (or the sensors and actuators themselves) can be modified by a malicious agent then the control of the physical plant can be covertly appropriated. A parameterised decoupling structure is introduced which allows the covert agent a wide range of control actions on the physical plant while remaining undetectable from the point of view of the original networked controller. The designer of the covert agent need only have a model of the physical plant; knowledge of the networked controller is not required. A MIMO process control example (based on the control of irrigation canals) is used to illustrate the concepts.