De l'Ingénierie des Besoins à l'Ingénierie des Exigences : Vers une Démarche Méthodologique d'Ingénierie de Systèmes Complexes, de Vérification et de Validation Appliquée à l'Informatisation des PME

摘要

Most enterprises, and especially SMEs, must develop their business in very competitive and rapidly changing fields. Where they have to adapt to volatile customers who want to find cheaper products and services and that are more corresponding to their needs. The SME is then confronted with problems of responsiveness and flexibility in responding to these customers. As an effect, it seeks to reduce the costs and time to market and to provide high quality and innovative goods and services. The SME’s information system is an asset on which it can rely to implement this strategy and so to maximize its responsiveness and flexibility but also to reach the sought profitability and quality. These are key qualities that guarantee autonomy and recognition, qualities that are highly needed by any SME. The Information system is indeed the drive belt of information not only inside the enterprise, between decision and operational systems proving added value of the enterprise, but also within its environment that includes its external partners. Part of this information system is computerized. It stores and processes the information needed by the different decision-making, business and support processes that serve the enterprise’s strategy. It is crucial to understand the features, interfaces and data that make up this computerized system and develop them according to the needs of SME. The SME is therefore tempted to embark, alone or accompanied, in so-called computerization projects i.e. projects for the development or improvement of its computerized system. We are interested in projects aimed at developing management applications of SMEs. The SME – then assuming the role of project owner – along with the development team – supporting the role of project management – have to share a common vision of the computerization needs. They are then called upon to carry out jointly requirements engineering (RE) activities. RE guides the SMEs to be able to describe and formalize its needs. It then allows the development team to specify more formally these needs as requirements which then define the required development work. RE is often carried out with the assistance of project owner support. This crucial step remains difficult for SMEs. It is most often performed by the development team itself to address the lack of resources, time and skills of SMEs. However, the involvement of the SME’s members is vital to the success of any computerization project, especially if it permanently affects the functioning of the enterprise. This work, developed through a collaborative with the company RESULIS, consisted in developing a requirements engineering method which offers SMEs concepts, simple languages, modeling and verification means that are easily and intuitively manipulated and provide sufficient and relevant formalization of the SME’s requirements. This method is based on principles derived from both enterprise modeling and systems engineering fields for requirements elicitation. Semi-formal verification and validation means are applied to guarantee some expected qualities of the resulting requirements. The method is also integrated in the model driven development cycle to enable a posteriori the production of prototypes and make interoperable the languages and tools used by both the SME and the development team.