System Requirements Engineering

1The Requirements Engineering Process

Requirements engineering is a field that is widely addressed in systems engineering. As the latter are becoming increasingly complex, requirements engineering has become essential, even taking on important contractual aspects. The purpose of this chapter is to present the context and associated definitions and to position requirements engineering in systems engineering processes [ROB 13]. The modeling and its contributions are then presented. Finally, its connection with project management is discussed.

1.1. Background and main definitions

Our focus is on systems engineering, as defined under ISO 15288:

“An interdisciplinary approach governing the total technical and managerial effort required to transform a set of stakeholder needs, expectations, and constraints into a solution and to support that solution throughout its life.” [ISO 15a]

This is true regardless of the nature of this system, as long as it is a “combination of interacting elements organized to achieve one or more stated purposes”, as specified in the main systems engineering standards such as ISO 15288 [ISO 15a] and ISO 29110 [ISO 18a]. In addition, we will use, as in these repositories, the paradigm of “system thinking” as opposed to a Cartesian method of problem solving. The main advantages can be given as follows:

• – consider the system as a whole;
• – consider the entire life cycle of the system [ISO 19];
• – identify the interrelationships among the parts that compose ...