Towards a verification of the rule-based expert system of the IBM SA for OS/390 Automation Manager

Abstract

We formally verify consistency aspects of the rule-based expert system of IBM's System Automation software for IBM's e-server zSeries. Starting with a formalization of the expert system in propositional dynamic logic (PDL), we are able to encode termination and determinism properties. To circumvent direct proofs in PDL or its extension /spl Delta/PDL, we further translate versions of the occurring decision problems to propositional logic, where we can apply advanced SAT and BDD techniques. In our experiments we revealed some inconsistencies, and after correcting them, we successfully verified a non-looping property for a part of the expert system.