A FORMAL APPROACH TO SCENARIO INTEGRATION

The scenario technique is an interesting approach for eliciting requir ements. A formal approach to scenario generation has made it even more attractive. The next logical step is to integrate several scenarios i nto one single, consistent, specification. In this work, a mixed appro ach, involving formal and informal steps is proposed for performing th is task. The system's formal specification is expressed as a finite st ate machine. The specifications of two interacting scenarios are integ rated in a procedure involving formal and informal steps. Then several algorithms based on the properties of the model, are applied to detec t three classes of errors: mistakes made by the analyst during the inf ormal steps of the integration, inconsistencies between the scenarios, and incompleteness of both scenarios. Each algorithm detects the corr esponding specification errors and in addition, suggests the correctio ns to apply. The formal techniques applied in this work could be the b asis of a CASE tool for scenario-based requirements engineering.