that the types of the work products mentioned in Figure 2.2 on the left side of the V-model are just an illustration.In practice they come under many different names. References for generic work products include the Capability Maturity Model Integration (CMMi) or the 'Software life cycle processes' from ISO/IEC 12207. The CMMi is a framework for process improvement for both system engineering and software engineering. It provides guidance on where to focus and how, in order to increase the level of process maturity [Chrissis et al .. 2004]. ISO/IEC 12207 is an integrated software life cycle process standard that is rapidly becoming more popular.