Requirement model for a high quality service system: For reducing both costs of planning and development

This paper proposes a 2×2 requirement chart based on a requirement model for a service system. The model was developed to attention on critical issues and retains the essence of the requirement types. Therefore, we can use it as a template for requirement design. On the other hand, the chart is efficient to identify the items in ConOps (Concept of OPerationS), a standard provided by IEEE. The main purpose of the chart is to execute the requirement development process sufficiently, which is in the Concept Stage within the service lifecycle, without increasing the cost. Utilizing this chart also reduces the extra costs of the Development Stage caused by errors that are extremely difficult to estimate during the planning phase. High quality service system won't have cost overrun problem in any phase. We established two identical enterprise service systems each using different cases and compared their development costs. The first case is to proceed with systems architecture development and systems designing based on the initial requirements provided by sponsors and then move on to the Development Stage. The second case is to use the 2×2 requirements chart that we have proposed to develop ConOps in the same stage.