Digital Twin Integrity Protection in Distributed Control Systems.

The notion of Cyber-Physical Systems (CPS) reflects real-time control applications that are realized through distributed coordination among multiple modules. Such coordination is founded on frequent exchange of status and sensor data among the various modules so that actuation decisions are made autonomously. The formation of digital twins has emerged as an effective methodology where data-driven models are employed to enable effective decision making. Hence, the accuracy of these models become very critical for system stability; no wonder data forgery is a major threat for CPS where an attacker strives to inject faulty data to degrade the digital twin of one or multiple modules. Such an attack could be taking the form of impersonating a component, or manipulating/replaying status update packets. This paper proposes an effective scheme for mitigating such a threat by employing hardware-based fingerprinting primitives, namely, Physically Unclonable Functions (PUFs). The proposed PUF-based Integrity protection of digital Twins (PIT) scheme, ensures the authenticity of data sources, and the freshness and integrity of the shared status. PIT is validated using analysis and prototype implementation on an FPGA.