Practical Experience with Viewpoint-Oriented Requirements Specification

The notion of viewpoints as a means of eliciting and formulating requirements is now well known. However, there is little practical evidence that viewpoint-based requirements methods scale up to address real problems. This paper presents a detailed case study based on a medium-sized system, and illustrates how a viewpoint-based requirements method can be used to structure and specify system requirements. The case study is intended to serve two purposes: first, to demonstrate the scalability of viewpoint-based requirements methods; and second, to act as a shared example for other researchers in the field to test their techniques and methods. The case study is based on an electronic document delivery and interchange system (EDDIS). The requirements are presented as they appeared in the original user requirements document. The paper concludes by outlining the lessons learnt in applying VORD to EDDIS, and proposes a set of 10 comparators that other researchers can use to compare their approaches and techniques.