Sensor Data Protection in Cyber-Physical Systems

Cyber-Physical Systems (CPS) always have a physical part that can interact with sensors and actuators. The data that is read from sensors and the data generated to drive actuators is crucial for the correct operation of this class of devices. The majority of the implementations trust the data being read from sensors and the outputted data to actuators. Real-time validation of the input and output of data for any system is crucial for the safety of its operation. This paper proposes an architecture for handling this issue through smart data guards, which are detached from sensors and controllers and act solely on the data. This mitigates potential issues of malfunctioning sensors and faulty control signals, and intentional sensor and controller attacks. The data guards know the expected data, can detect anomalies and can correct them in real-time. This approach adds more guarantees for fault-tolerant behavior in the presence of attacks and failures.