Hidden states in reaction systems

Pushing forward a previous investigation on security of reaction systems, we introduce new state based security properties. Assume there are some states of a reaction system that are in some sense critical, and that we want to hide whether the system reaches them. We define new security properties that guarantee that an external observer who has only a partial knowledge on the objects provided by the environment cannot infer whether a secret state is reached by the system. We also propose an effective method for verifying such properties. The verification method is based on a newly defined extension of the concept of formula based predictor to set of states.