Multi-Source Multi-Domain Data Fusion for Cyberattack Detection in Power Systems

Abstract

Modern power systems equipped with advanced communication infrastructure are cyber-physical in nature. The traditional approach of leveraging physical measurements for detecting cyber-induced physical contingencies is insufficient to reflect the accurate cyber-physical states. Moreover, deploying conventional rule-based and anomaly-based intrusion detection systems for cyberattack detection results in higher false positives. Hence, independent usage of detection tools of cyberattacks in cyber and physical sides has a limited capability. In this work, a mechanism to fuse real-time data from cyber and physical domains, to improve situational awareness of the whole system is developed. It is demonstrated how improved situational awareness can help reduce false positives in intrusion detection. This cyber and physical data fusion results in cyber-physical state space explosion which is addressed using different feature transformation and selection techniques. Our fusion engine is further integrated into a cyber-physical power system testbed as an application that collects cyber and power system telemetry from multiple sensors emulating real-world data sources found in a utility. These are synthesized into features for algorithms to detect cyber intrusions. Results are presented using the proposed data fusion application to infer False Data and Command Injection (FDI and FCI)-based Man-in-The-Middle attacks. Post collection, the data fusion application uses time-synchronized merge and extracts features. This is followed by pre-processing such as imputation, categorical encoding, and feature reduction, before training supervised, semi-supervised, and unsupervised learning models to evaluate the performance of the intrusion detection system. A major finding is the improvement of detection accuracy by fusion of features from cyber, security, and physical domains. Additionally, it is observed that the semi-supervised co-training technique performs at par with supervised learning methods with the proposed feature vector. The approach and toolset, as well as the dataset that is generated can be utilized to prevent threats such as false data or command injection attacks from being carried out by identifying cyber intrusions accurately.

Keywords

• Multi-sensor data fusion
• intrusion detection system
• co-training
• supervised learning
• unsupervised learning
• cyber-physical systems