Decision Networks for Security Risk Assessment of Critical Infrastructures

We exploit Decision Networks (DN) for the analysis of attack/defense scenarios in critical infrastructures. DN extend Bayesian Networks (BN) with decision and value nodes. DN inherit from BN the possibility to naturally address uncertainty at every level, making possible the modeling of situations that are not limited to Boolean combinations of events. By means of decision nodes, DN can include the interaction level of attacks and countermeasures. Inference algorithms can be directly exploited for implementing a probabilistic analysis of both the risk and the importance of the attacks. Thanks to value nodes, a sound decision theoretic analysis has the goal of selecting the optimal set of countermeasures to activate.