Double closed-loop NCSs modeling for security control and a defense framework design

This paper presents the design of double closed-loop security control structure. This structure is divided into two parts. First of all, sensor-controller-actuator loop completes the transmission of control signal output and measurement signal feedback. During the transmission process, the effects of uncertainties, perturbations, faults and attacks are coupled. Further, controller-detector loop is adopted to detect the faults and attacks due to their actual effect on NCSs. In addition, a novel anti-attack framework is proposed based-on the adversary's behavior and effects on NCSs. By this framework, system security conditions are obtained, and two algorithms are design to determine the attacks during the output and feedback channels, flow charts of algorithms are presented as well.