A framework for decentralized opacity in linear systems
Bhaskar Ramasubramanian, Rance Cleaveland, Steven I. Marcus · 2016
We formulate several notions of decentralized opacity for cyberphysical systems in the presence of multiple adversarial observers. Broadly speaking, we study the following cases: i) the presence or lack of a centralized coordinator, and ii) the presence or absence of collusion among the adversaries. In the case of colluding adversaries, we derive a condition for non-opacity that depends on the structure of the directed graph representing the communication between adversaries. Finally, we define a notion of opacity where the condition that the outputs be indistinguishable is relaxed.