Systems and Requirements Engineering: An Approach and a Software Tool for the Interactive and Consistent Functional Requirement Specification

Managing the complexity of modern systems is a current challenge involving all the phases of a system development process. Complex systems also mean a great number of stakeholders involved and just as many needs to satisfy. In the Systems Engineering approach for complex systems design, Requirements Engineering provides methods to collect stakeholders needs and to translate them into system requirements. Furthermore, several tools currently allow creating requirements repository and manage their properties and changes. Traceability is also implemented to verify design against requirements. Although there are several standards and guidelines which provide criteria and rules for writing requirement statements, it is still missed a process that drives the user in the correct requirement construction. The present paper faces the requirement specification process in order to provide tools that can support and drive designers in the requirements writing. In particular, the paper (i) provides a framework for writing syntactically correct requirements that can be early verified against pre-defined criteria such as clarity, singularity, conformity, and descriptiveness; (ii) presents a software tool for creating well-defined requirements statements offering the user the possibility to formulate “correct requirements by construction”. The driven definition of system requirements leads to a well-defined specification, thus allowing time and efforts reduction during the following steps of system development process.