Hybrid software process simulation modeling for analyzing software-intensive system acquisition

Abstract

Many sources have identified that Software-Intensive System Acquisition (SISA) projects %in defense sector lacked the acquirer``s technical and managerial capability, which makes the requirements out of control and the development schedule delayed. In this study, we develop a Software Process Simulation Model (SPSM) for SISA to analyze the associated problems with the lack of the acquirer``s competence and demonstrate the effects of the acquirer``s activities. To develop the SPSM for SISA, we propose a new simulation modeling approach. We develop a hybrid software process simulation modeling approach using DEVS (Discrete Event System Specification) to incorporating the dynamic interactions among stakeholders (end user, acquirer, and developer) of SISA with discrete behavior (e.g., discretely occurred problem reporting, milestone review, phase transition, unexpected subcontract change, etc.) of SISA in a systematic way. We also develop a dynamic interaction estimation method using COCOMO II to alleviate the problem of the lack of the historical project data on SISA. The specific problems we concentrate on are creeping requirements, which are emerging slowly after the initial requirements have been agreed, and Action Items (AIs), which are the documented events, tasks, activities, or actions that need to take place. The simulation model analyzes the bad influences of large volume of requirements creep and the effects of the acquisition policies for managing creeping requirements on the cost, schedule, and quality. Our simulation model can provide valuable information for deciding how to apply the policies according to the purpose of the project. The simulation model also analyzes the project schedule delay caused by AIs. The AI processing process consisting of AI generation, processing, and approval is discretely occurred and also affected by the dynamic project environment including phase progress rate, level of stakeholder``s conflict, etc. Finally, ...