NIST and University of Maryland researchers developed approaches for determining suitable investments for improving the robustness of complex systems, which are described in Investments in Robustness of Complex Systems: Algorithm Design and presented at Complex Networks 2022.
Complex systems consist of multiple networks – information, communications, power systems – and depend on each other to deliver services. Their interdependence also makes it possible for a local failure, or infection of a network, to spread to other systems. Thus, a major challenge is how to optimize investments to make complex systems robust enough to withstand such problems and keep operating with minimum or no disruptions – a subject that has been studied extensively.
Unlike past studies, NIST and University of Maryland researchers considered optimal investments for both resilience and recovery. In one approach, researchers devised an efficient gradient method to solve problems. To help determine optimum investments for a complex system’s resilience and recovery, researchers designed an algorithm which provided a quality solution, with bounds for optimum investment.
In another approach, researchers defined the technical conditions for a complex system’s operations and susceptibility to failures and infections and formulated a lower bound for an optimum investment, covering resilience and recovery. This formulation also helped determine a feasible solution and upward bound for an optimum investment. The effectiveness of both approaches was demonstrated, using numerical studies.