Simulation-based goal tree success tree for the risk analysis of cyber-physical systems

Cyber-Physical Systems (CPSs) can be subjected to random failures of hardware components and to intentional breaches in cyber components. In a previous paper, the authors have proposed the Goal Tree Success Tree Master Logic Diagram (GTST-MLD) as a framework to jointly treat these aspects in the risk analysis of CPSs. In this work, a simulation-based method is proposed to assign the values of the weights of the GTST-MLD. An application is carried out considering the digital Instrumentation and Control (I&C) system of the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED)). A number of simulations are run for different types of cyber attacks at random times and magnitudes, and the critical parameters of different failure scenarios are collected, and properly manipulated to estimate the weights of the GTST-MLD.