Combining Goals and Functional Requirements in a Scenario-based Design Process

While promising approaches to early system design using scenarios have been proposed, no design process is available that guides scenario-based development. We present a model that combines scenarios both with functions and goals. Functions are required to make the desired behaviour of some scenario happen in order to achieve one or more goals. Using this model, we propose a systematic and concrete design process that is both model-driven and data-driven. Our design process supports the transition from the current to a new system and guides the design of a new system. In addition, this process makes it possible to detect redundancy and to improve both completeness and understandability of the resulting design. We have applied our approach in real-world projects, and our experience suggests the utility of this approach.