Towards a framework for quantifying system non-functional data definition and database requirements

In practice, during the system requirements gathering phase, the focus is often on the functional requirements of the system, while non-functional requirements are often captured by system analysts at a very global level. The European ECSS series of standards for the aerospace industry includes data definition and database requirements as one of sixteen types of non-functional requirement (NFR) for embedded and real time systems. A number of data definition and database related concepts are dispersed throughout the ECSS standards to describe at varying levels of details the various types of candidate data definition and database requirements at the system, software, and hardware levels. This paper organises these dispersed data definition and database concepts into a standards-based reference framework of system data definition and database requirements. The availability of this generic, and detailed, reference model can facilitate the early identification and specification of the system data definition and database-NFR and their detailed allocation as specific data definition and database functions to be handled by the specified allocation to hardware, software or in a specific combination of both.