Recent progress on cascading failures and recovery in interdependent networks

Complex networks have gained much attention in the past 20 years, with thousands of publications due to their broad interest and applicability. Studies initially focused on the functionality of isolated single networks. However, crucial communication systems, infrastructure networks and others are usually coupled together and can be modeled as interdependent networks, hence, since 2010 the focus has shifted to the study of the more general and realistic case of coupled networks, called Networks of Networks (NON). Due to interdependencies between the networks, NON can suffer from cascading failures leading to abrupt catastrophic collapse. In this review, using the perspective of statistical physics and network science, we will mainly discuss recent progress in understanding the robustness of NON having cascading failures features that are realistic for infrastructure networks. We also discuss in this review strategies of protecting and repairing NON.