Applying a model-based approach to IT systems development using SysML extension

Model-based system engineering (MBSE) is regarded as an effective way of developing systems. We are now applying the model-based approach to IT system development/integration (SI) because we urgently need to reduce the cost of SI. However, there are various challenges imposed when applying MBSE to SI. One of these is that reducing the cost to update models is more significant than that in other MBSE domains such as embedded systems. We adopted SysML to handle these issues and extended it to modeling IT systems. We present the details on this SysML extension and how it overcame these issues. We are developing an in-house SI-support tool called "CASSI", which evaluates the non-functional requirements; performance and availability of the IT system's models written in that extended manner and helps these models to be reused. This paper also includes industrial case studies of CASSI, and its effectiveness is discussed.