Representation of business processes at multiple levels of abstraction (strategic, tactical and operational) during the requirements elicitation stage of a software project, and the measurement of their functional size with ISO 19761

Abstract

This thesis aims at helping software engineers and business analysts to better model business processes when those models are meant to be used: for software requirements specification, and for functional size measurement purposes. The research goal of this thesis is to contribute to the representation of business processes for its use during the requirements elicitation stage of a software project. To achieve this goal, two research objectives are clearly defined: 1. To propose a novel modeling approach that generates business process models intended to be used in a software requirements elicitation activity. The modeling approach should not significantly increase the complexity of the modeling notations used to represent the business processes; and it must allow the active participation of the various stakeholders involved in a typical software project in order to represent, in a consistent and structured way, their needs and constraints. 2. To develop a procedure to measure the functional size of a software application from the business process models representing it. This measurement procedure should be compatible with the COSMIC ISO 19761 standard; and it should be able to be used independently of the modeling notation used to represent the business process. To achieve the first objective, this thesis proposes a novel modeling approach (coined BPM+) that models business processes at three levels of abstraction: strategic, tactical and operational. An a priori version of BPM+ was designed based on the findings of the literature review. This a priori version was iteratively refined through a pilot case study in industry, a series of ontological analyses, and a survey of experts. As a result, a reviewed version of BPM+ was proposed. The reviewed version was evaluated through a second case study in industry. Therefore, the design of BPM+ has been based on a triangulation of evidences obtained from various sources. To achieve the second objective, the measurement procedure was developed from an analytical comparison between the specifications of COSMIC and those of the modeling notations selected for this research (i.e. BPMN and Qualigram). This analytical comparison helped to define a set of modeling guidelines for the business application software domain. The comparison also allowed defining a set of mapping rules between the modeling notations’ constructs and the COSMIC concepts. In addition, the modeling guidelines were adapted for their application to the real-time software domain. The measurement procedure was evaluated by comparing its measurement results to those obtained in COSMIC reference case studies. The research results demonstrate that: 1. BPM+ allows generating business process models that represent in a consistent and structured way the needs of various stakeholders. 2. Qualigram notation is better suited to BPM+’s design. In addition, Qualigram notation is preferred to be used for non-IT stakeholders, while BPMN is preferred for IT stakeholders. 3. The measurement procedure was successfully applied using two different notations: Qualigram and BPMN, and in two different software domains: the business application domain and the real-time domain. 4. The accuracy of the measurement procedure is in conformity with all the rules of the ISO 19761 standard