Toward a Unified Model for Requirements Engineering

One of the problem areas in requirements engineering has been the integration of functional and nonfunctional requirements and use cases. Current practice is to partition functional and nonfunctional requirements such that they are often defined by different teams. Functional requirements are defined by writing text-based use cases or, less frequently, creating a business model, then walking through the use cases, and extracting (often in a haphazard fashion) detailed requirements. The problem is exacerbated when analysts are at different locations. Siemens experience with outsourcing and offshoring has demonstrated that the use of graphical languages significantly reduces cultural and communication problems when teams (e.g. analysis and design) are at different locations. Tracing between functional and nonfunctional requirements, use cases, hazards and features is complicated by the use of different Medias. Introducing new symbols and new relationships allows the creation of a unified model with intrinsic tracing. This, in turn, improves clarity and facilitates communication when teams are at different locations and/or are lacking in domain expertise