Searching Better Rewiring Strategies and Objective Functions for Stronger Controllability Robustness

Rewiring is a common strategy for enhancing the controllability robustness of complex networks. In this brief, rewiring strategies including the degree-preserving strategy, underlying-topology-preserving strategy, and unconstrained-rewiring strategy, are compared and analyzed. Since measuring the true controllability-robustness values by simulations is time-consuming hence impractical, three surrogates are proposed for improvement, namely initial controllability, critical nodes exposure, and network heterogeneity. Combinations of rewiring strategies and objective functions are compared to the random edge-rectification strategy. Extensive simulations show that the random-edge rectification outperforms all the other strategies in enhancing the controllability robustness, but significantly changes the resulting network topology. In effect, the degree-preserving rewiring strategy performs as well as the unconstrained-rewiring strategy on homogeneous networks. The results also show the effectiveness of using the critical nodes exposure as a surrogate for the true controllability robustness.