Information flow properties are a way of specifying security properties of systems. A system is viewed as generating traces containing confidential and visible events (only the latter being observable by a low-level user) and the information flow properties specify restrictions on the kind of traces the system may generate, so as to restrict the amount of information a low-level user can infer about confidential events having taken place (or not) in an execution. Mantel identifies "basic security predicates or BSPs and shows them to be the building blocks of most of the known trace-based...