On allocating interconnecting links against cascading failures in cyber-physical networks

We consider a cyber-physical system consisting of two interacting networks, i.e., a cyber-network overlaying a physical-network. In the event of attacks, due to the interdependence between the networks, node failures in one network may result in a cascade of failures affecting both networks - potentially leading to the collapse of the entire infrastructure. Robustness against such catastrophic failure hinges heavily on the allocation of the interconnecting links that connect nodes in one network to nodes in the other network for proper functioning. Assuming that no information about the degree distribution within each of the two constituent networks, we develop a uniform allocation strategy that allots inter-network links equally across all nodes. Our findings indicate that, from a network resilience perspective, uniform allocation of internetwork edges yields a significant gain compared to random allocation.