Abstract
Large-scale distributed control systems such as those encountered in electric power networks or industrial control systems must be assumed to be vulnerable to attacks in which adversaries can take over control at least part of the control network by compromising a subset of nodes. We investigate Structural Controllability properties of the control graph in Linear Time-Invariant systems (LTI), addressing the question of how to efficiently re-construct a control graph as far as possible in the presence of such compromised nodes. We study the case of sparse Erdos-Renyi Graphs with directed control edges and seek to provide an approximation of an efficient reconstructed control graph while minimising control graph diameter. The approach is based on a Block Decomposition of a directed graph, allowing to identify cut-vertices and cut-edge. This results in faster re-construction of Power Dominating Set (PDS) structure, and ultimately the re-gaining of control for operators of control systems by applying three phases.