CyPSV: A Vulnerability Assessment Metric for a Cyber Physical System Against Cyber Attacks

CyberPhysical Systems (CPS) are the intelligent systems where physical processes are automated and controlled by computer algorithms. In CPS, the coming together of the information technology and physical systems in closed loop have revolutionised our world with fast and efficient products and services, real-time automated analysis and data flow, resource optimization and complex executions. The increase in complexity of the traditional systems has also increased the risk of cyber attacks to the system. So a strategized and directed planning and operation is required for such systems to work smoothly against cyber-attacks. In this paper, for vulnerability assessment of a CPS, it is proposed to expose the system with cyber attacks and analyse its implications on the system. Vulnerability of the CPS against such attacks is calculated through a newly proposed index, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Cyber Physical System Vulnerability (CyPSV)</i>. The novel implementation of the proposed vulnerability assessment approach is done on the smart power distribution system which has a profound communication network as well as advanced physical infrastructure. Extensive analysis has been carried out on IEEE-14 bus system and a modified IEEE-33 bus system. The measurement data is generated synthetically using real world load profile and an attack vector generated through NSGAII optimization algorithm is launched into the measurement data. The impact of the attack on the system states is analysed and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${\bm {CyPSV}}$</tex-math></inline-formula> is calculated which would provide the information about the system health against cyber attacks. The proposed methodology would advance the development of cyber attack resilient CPS.