A memetic algorithm for enhancing the robustness of scale-free networks against malicious attacks

The robustness of the infrastructure of various real-life systems, which can be represented by networks and manifests the scale-free property, is of great importance. Thus, in this paper, a new memetic algorithm (MA), which is a type of effective optimization method combining both global and local searches, is proposed to enhance the robustness of scale-free (RSF) networks against malicious attacks (MA) without changing the degree distribution. The proposed algorithm is abbreviated as MA-RSFMA. Especially, with the intrinsic properties of the problem of optimizing network structure in mind, a crossover operator which can perform global search and a local search operator are designed. In the experiments, both synthetic scale-free networks and real-world networks, like the EU power grid network and the real Internet at the level of autonomous system (AS), are used. MA-RSFMA shows a strong ability in searching for the most robust network structure, and clearly outperforms existing local search methods.