Runtime verification of timing and probabilistic properties using WMI and .NET

Reliability and availability are key issues to distributed service-oriented systems. We present a methodology for run-time verification of reliability and availability properties for distributed architectures. Our approach generalizes the concept of design-by-contract to contracts involving time and probabilities. We define a language for contracts based on probabilistic real time computational tree logic (PCTL). We provide a formal semantics for this language based on possible execution traces of a system. Then we describe a .NET-based system for monitoring contracts, built upon the Windows Management Instrumentation (WMI) framework.