Analysis of the Robustness of Critical Infrastructures Within a Multistate Systems-of-Systems Framework in the Presence of Epistemic Uncertainties

In this paper, we look at the robustness of connected critical infrastructures under a systems-of-systems framework, taking into account:(1) the dependencies and interdependencies among the components of a critical infrastructure and between different critical infrastructures, respectively; (2) the variability of the performance of each component by means of a multistate model; and, (3) the epistemic uncertainty in the transition probability between different component states by means of probability intervals. We adopt the Goal Tree Success Tree - Dynamic Master Logic Diagram for system modelling and we perform a quantitative assessment of the systems-of-systems performance by Monte Carlo simulation. We illustrate the approach by way of a simplified case study consisting of two interdependent infrastructures (electric power system and a gas network) and a supervisory control and data acquisition system connected to the gas network.