Abstract

In this thesis, we present a mathematical formulation for increasing cyberphysical system security. This model allows a system administrator to use assumptions about exposed signals to derive defense strategies meant to mitigate the system's vulnerability to feedback perturbation attacks. We begin with a survey of game theory with the goal of building the concepts of resource and security games. We then introduce our model, which is a security game; targets in this game are exposed signals in the model map of the system, and resources are perturbed or introduced dynamical relationships between these signals. This formulation, called the masked-perturbation model, allows a system administrator to use the tools or game theory and robust control to derive an explicit solution to an optimization problem, which directly provides a defense strategy that is employable on their real-world system. We then provide an example of how this model is used to design a defense strategy for a two-input-two output system. Finally, we explore unanswered questions which would further this model and improve applicability in large systems, mainly due to the issue of tractability in exponential action spaces.

Degree

College and Department

Computer Science

Rights

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