Security Vulnerability Assessment of SCADA System for Evidence-Based Reasoning and Bayesian Network

摘要

To assess the information security vulnerability of the wind farm SCADA system quantitatively, this paper proposes an evaluation method based on evidence-based reasoning and Bayesian network. Firstly, Analyze the wind farm SCADA system and establish an evidence-based reasoning model for system vulnerability. Secondly, based on the Bayesian theorem, the link model is used to link the function to construct the fragile Bayesian network of each path to the inference model. Then, using AHP and Bayesian inference to quantify the nodes in the inference model, the conditional probability between nodes and the posterior probability of the nodes is calculated. The hypothesis probability is used as the criterion for vulnerability assessment, and the vulnerabilities of node, path, and whole system are obtained. Finally, the simulation results prove that this method helps managers to assess the information security vulnerability of SCADA system, and then take effective defense measures.