The Maritime Transportation System (MTS) is critical to global commerce and civilization. In 2017, more than 80% of global merchandise trade in volume and 67% of its value in 2017 [1] relied upon the MTS. Nationally, the MTS accounted for more than $4.6 trillion of economic activity, a quarter of the US GDP, in 2014 [2]. Shipping ports rely upon critical infrastructure systems to support more efficient business functions distributed across multiple stakeholders. Larger trade volumes and a desire by shippers for supply-chain transparency are driving increased adoption of automation and integration across multiple stakeholder systems. As a result, intelligent adversaries have the ability to compose once-siloed threat models by viewing the port as a complex, system of systems. Our framework provides the means by which stakeholders can simulate multilayered networks to explore how changes in measures of performance in communications/IT networks translate via cross-infrastructure dependencies to affect measures of performance in stakeholder transportation networks (such as those defined in service contracts). Practically, this enables stakeholders in a security committee to run through what-if scenarios for theoretically-possible cyber attacks and understand how business processes would be affected.
