Requirements Modeling for Families of Complex Systems

This paper introduces an approach to the specification of system families. The main ingredient of this approach is the definition of use cases hand in hand with a requirements object model. Instead of specifying individual systems, we specify a domain, i.e., a conceptual space of possible systems, in which individual systems can be defined by fixing a number of variation points. In that way we obtain a strong cohesion within the family and concise specifications of its members. We also describe a process suitable for this specification approach and indicate how the transition to the design phase can take place. Our approach was validated in one large project and several smaller ones.