Alternative composition analysis of noninterference in cyber-physical system

At present, a rather big challenge to model cyber-physical systems is to stand for the interactions between physical level and cyber level. Researchers are faced with the trouble in the analysis of information security property of noninterference in cyber-physical systems because of the physical components and behavior appended to cyber components and systems. A new method is put forward with Petri net for working out this problem effectively by composing the complicated and large systems with simple and small systems. Meanwhile, it accomplishes the noninterference information flow security property. In this paper, this method is used to analyze the information security property of noninterference and its alternative composition in cyber-physical systems. This research provides a new formal method to explore information security property of noninterference and a sufficiency and necessary condition of alternative composition of noninterference of information security model in cyber-physical systems.