2014/07/16 by Béatrice Bérard, Krishnendu Chatterjee, Bérard, Béatrice +3 · 2 citations
Computer Science · #Advanced Malware Detection Techniques #Cryptography and Security (cs.CR) #Distributed systems and fault tolerance #FOS: Computer and information sciences #Formal Methods in Verification #cs.CR
paper · pdf · doi:10.48550/arxiv.1407.4225
openalex publication_date 2014/07/16 · arxiv created 2014/09/01 · arxiv updated 2014/09/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Opacity is a generic security property, that has been defined on (non probabilistic) transition systems and later on Markov chains with labels. For a secret predicate, given as a subset of runs, and a function describing the view of an external observer, the value of interest for opacity is a measure of the set of runs disclosing the secret. We extend this definition to the richer framework of Markov decision processes, where non deterministic choice is combined with probabilistic transitions, and we study related decidability problems with partial or complete observation hypotheses for the schedulers. We prove that all questions are decidable with complete observation and ω-regular secrets. With partial observation, we prove that all quantitative questions are undecidable but the question whether a system is almost surely non opaque becomes decidable for a restricted class of ω-regular secrets, as well as for all ω-regular secrets under finite-memory schedulers.