Risk-based task scheduling approach for integrated control of system safety and cyber security in industrial control systems

Abstract

System safety and cyber security have a great effect on system reliability which is the foundation of keeping system running-normally. Although safety and security controls can reinforce each other mutually, contradictions between them also exist, such as resource competition that may cause serious damage. This paper puts forward a risk-based task scheduling approach for the integrated control of system safety and cyber security in industrial control systems (ICSs). In this approach, an integrated task model covering both safety task and security task is proposed, which describes the relationship between task and risk in detail. And the change of real-time risk during the enforcement of these tasks is analysed. These tasks are scheduled through an optimal scheduling scheme which means the risk decrease as soon as possible and is always acceptable based on genetic algorithm. Further, simulation results show that the proposed approach is effective for task scheduling and real-time risk control.