A hybrid systems model to simulate cyber interdependencies between critical infrastructures

Critical infrastructures (CI) depend on communications and information technology infrastructure (CITI) for many of their key functionalities, which is known as cyber interdependency. In this paper, we presented a cyber interdependency simulation technique that is based on the idea that overall performance of a CI network is determined by the behaviour of its components at multiple time scales. Accordingly, for cyber interdependency simulation, we decomposed CI network into two time scales; regular CI events are captured in large time-steps and data communication network events are captured in smaller time-steps. Two different simulators are used for each of these partitions and results from both simulations are synchronised appropriately. A real life example is presented to demonstrate the accuracy and usefulness of our approach. The hybrid simulation model gives significant flexibility to plug-in domain specific models into the critical infrastructure simulator for accurate and efficient solution.