Thomas Lumpp

The role of ontologies in autonomic computing systems

The goal of IBMs autonomic computing strategy is to deliver information technology environments with improved self-management capabilities, such as self-healing, self-protection, self-optimization, and self-configuration. Data correlation and inference technologies can be used as core components to build autonomic computing systems. They can also be used to perform automated and continuous analysis of enterprise-wide event data based upon user-defined configurable rules, such as those intended for detecting threats or system failures. Furthermore, they may trigger corrective actions for protecting or healing the system. In this paper, we discuss the use of ontologies as a high-level, expressive, conceptual modeling approach for describing the knowledge upon which the processing of a correlation engine is based. The introduction of explicit models of state-based information technology resources into the correlation technology approach allows the construction of autonomic computing systems that are capable of dealing with policy-based goals on a higher abstraction level. We demonstrate some of the benefits of this approach by applying it to a particular IBM implementation, the eAutomation correlation engine.

Detection of dynamic execution errors in IBM system automation's rule-based expert system

We formally verify aspects of the rule-based expert system of IBM’s System Automation software for IBM’s zSeries mainframes. Starting with a formalization of the expert system in Propositional Dynamic Logic (PDL), we encode termination and determinism properties in PDL and its extension PDL. We then translate our decision problems to propositional logic and apply advanced SAT techniques for automated proofs. In order to locate real program bugs for each failed proof attempt, we apply extra formalization steps and represent propositional error formulae in concise normal form as Binary Decision Diagrams (BDDs). In our experiments, we revealed residual non-termination bugs in a tested program version close to shipment, and, after correcting them, we formally verified the absence of this class of bugs in the production code.