Continuous-Time Computational Aspects of Cyber-Physical Security

A wide variety of mixed digital-physical (cyber-physical) systems with complex and often loosely defined components are now deployed, whose behavior affect our daily lives in significant and sometimes critical ways. Cyber-physical systems (CPS) can provide much richer functionality, efficiency, autonomy, and reliability than manually controlled and loosely coupled systems. However, they also create inherent vulnerability related to privacy, security, robustness, and reliability of the underlying components and as a whole system. The mixed digital-physical aspect of such systems opens new and, as-of-yet, lightly explored opportunities for hybrid design, modeling, and analysis. Robust and safe systems must be designed and deployed to meet operational and security challenges. Additionally, the continuous-time nature of the physical components of these systems implies a fit for certain high-performance, low-power analog computing solutions. Here we survey existing efforts related to such risks and opportunities. We also tie the topics together and provide guidance to other researchers interested in exploring the hybrid aspects of mixed digital-physical systems.