An Integrated Scenario Management Strategy

Scenarios have proven effective for eliciting, describing and validating software requirements; however, scenario management continues to be a significant challenge to practitioners. One reason for this difficulty is that the number of possible relations among scenarios grows exponentially with the number of scenarios. If these relations are formalized, they can be more easily identified and supported. To provide this support, we extend the benefits of project-wide glossaries with two complementary approaches. The first approach employs shared scenario elements to identify and maintain common episodes among scenarios. The resulting episodes impose consistency across related scenarios and provide a way to visualize their interdependencies. The second approach quantifies similarity between scenarios. The resulting similarity measures serve as heuristics for finding duplicate scenarios, scenarios needing further elaboration, and scenarios which have not yet been identified, yielding valuable information about how well the scenarios provide coverage of the requirements. These two approaches, integrated with a scenario database, project glossaries, configuration management, and coverage analysis, form the basis of a useful and effective strategy for scenario management and evolution.