Deciding selective declassification of petri nets

Abstract

This paper considers declassification, as effected by downgrading actions D, in the context of intransitive non-interference encountered in systems that consist of high-level (secret) actions H and low-level (public) actions L. In a previous paper, we have shown the decidability of a strong form of declassification, by which D contains only a single action d∈ D declassifying all H actions at once. The present paper continues this study by considering selective declassification, where each transition d∈ D can declassify a subset H(d) of H. The decidability of this more flexible, application-prone declassification framework is proved in the context of (possibly unbounded) Petri nets with possibly infinite state spaces. © 2012 Springer-Verlag.