Using parameters and discriminants for product line requirements

Reuse and Requirements Engineering are very important for efficient and successful product development. However, there are many open issues for performing them well in practice, especially reuse of requirements. This paper addresses several of these issues by making use of parameters and discriminants for product line requirements. Discriminants are a special kind of requirement that differentiate one product from another. They represent qualitative variability in a product line model, while parameters represent quantitative variability. In this paper these techniques are combined in the form of parameterized discriminants. Using the techniques and a metamodel for the representation of a product line model, a stakeholder-viewpoint oriented process is defined for capturing product line requirements and constructing a product line model. From such a generic model and with well-defined semantics, selecting single product application requirements can be done systematically, guaranteeing the property that the resulting single product satisfies the constraints of the product line model. Even for unsystematic free selection as often used in practice, it can be formally verified whether this property holds. The approach is illustrated using a hypothetical mobile phone example and draws upon case study work with real-world requirements. © 2007 Wiley Periodicals, Inc. Syst Eng