OpenSESAME: an intuitive dependability modeling environment supporting inter-component dependencies

The paper proposes a novel modeling method for the evaluation of dependability measures of highly available systems. The proposed method, which has been implemented in the tool OpenSESAME (Simple but Extensive Structured Availability Modeling Environment), combines the advantages of Boolean methods and state space based methods. The tool supports the modeler with a set of well-defined, structured, intuitive input diagrams and tables, which are automatically transformed into GSPNs (Generalized Stochastic Petri Nets) for evaluation. To show the usefulness of the proposed method, it is applied to a model of a typical CompactPCI-based high availability system as can be found in the telecommunications area.