Improving the network robustness against cascading failures by adding links

In this paper, we explore the network robustness against cascading failures by adding links to the underlying network structure. Three link-adding strategies are compared, including random linking strategy (RLS), high-betweenness linking strategy (HBS), and low-polarization linking strategy (LPS). It is found that HBS is more effective than RLS to enhance the network robustness against cascades while the network exhibits the strongest robustness under LPS. Moreover, the effect of the total cost of link-adding is investigated. As the total cost grows, the advantage of LPS becomes more evident. Our work would be helpful for the design of networked systems.