Secure distributed estimation in cyber-physical systems

Distributed estimation is where the state of a dynamical system is to be estimated via a collection of geographically dispersed measurements over a sensor network. In order to implement the estimator, the sensors, in addition to sensing, implement a simple data fusion protocol that relies on inter-sensor communication. In this paper, we study distributed estimation of cyber-physical systems when there is an adversarial attack on the sensed and communicated information. We propose a novel methodology to address the detection of such attacks, and further incorporate appropriate remedial actions in the estimator. Our methodology is based on the notions of local consistency and nodal consistency and is further reinforced by the exploiting the underlying physical-layer in the cyber-physical description.