The LogicGuard Stream Monitor Specification Language Tutorial and Reference Manual

This report describes the design and use of the LogicGuard language for specifying stream monitors. These monitors observe streams of values (e.g., messages flowing through a network connection) and check whether the streams fulfill desired safety properties. These properties are described on a very high level of abstraction in a purely declarative way by notions that are derived from classical predicate logic, in particular by logic formulas that are quantified over stream positions. To raise the level of abstraction, auxiliary internal streams can be specified whose values are constructed from the values on the external streams by notions that are thar are similar to classical set builders. From the abstract specifications automatically executable monitors are generated which surveil the streams in real time and trigger warnings if violations of the specified properties are observed.