The resilience of cyberphysical systems to denial-of-service (DoS) and
integrity attacks is studied in this paper. The cyberphysical system is modeled
as a linear structured system, and its resilience to an attack is interpreted
in a graph theoretical framework. The structural resilience of the system is
characterized in terms of unmatched vertices in maximum matchings of the
bipartite graph and connected components of directed graph representations of
the system under attack. We first present conditions for the system to be
resilient to DoS attacks when an adversary may block access or turn off certain
inputs to the system. We extend this analysis to characterize resilience of the
system when an adversary might additionally have the ability to affect the
implementation of state-feedback control strategies. This is termed an
integrity attack. We establish conditions under which a system that is
structurally resilient to a DoS attack will also be resilient to a certain
class of integrity attacks. Finally, we formulate an extension to the case of
switched linear systems, and derive conditions for such systems to be
structurally resilient to a DoS attack.

By admin