Towards Improving Data Validity of Cyber-Physical Systems through Path Redundancy

Cyber-physical systems have shown to be susceptible to cyber-attacks. Incidents such as Stuxnet Attack and Ukraine power outage have shown that attackers are capable of penetrating into industrial control systems, compromising PLCs, and sending false commands to physical devices while reporting normal sensing values. Therefore, one of the critical needs of CPS is to ensure the validity of the sensor values. In this paper, we explore path diversity in SCADA networks and develop Path Redundancy to improve data validity. The proposed solution is shown to be able to effectively prevent data integrity attacks and detect false command attacks from a single compromised path or PLC. We provide detailed analysis on solution design and implement an application of the technique in building automation networks. Our cost-efficient and easy-to-deploy solution improves the resilience of SCADA networks.