Supporting Flexibility of the CMMI Process Framework with a Multi-layered Process Model

CMMI(Capability Maturity Model Integration) is a process framework which is organized by goals, practice and process area. The Maturity Level 3 stressed that the project level process must be tailored from the organization level process, that is to say, no matter how the project level process changes, it must satisfy the constraints of the organization level process. However, companies usually prefer to choose detailed and operational single-layered process models for applying CMMI. If some activities in process have been changed, the process model must be totally redesigned, this reduces the flexibility and increases the cost of adopting CMMI. In order to solve the above problems, this paper presents a multi-layered model, in which the upper layer is used to describe the CMMI organization level process (i.e., the software development lifecycle) and the lower layer is used to describe the project level process model (i.e., the procedure of each development group). At the same time, we provide delegation relationship in multi-layered process model to build the constraints between the upper layer and the lower layer process model, it brings the flexibility that the lower layered model (the project process) can change its activities on the premise that obeying the constraints of upper layered model (the organization process). Finally, in order to validate the practical effectiveness of this model, a CMMI case from GUODIAN Nanjing Automation Cd., LTD is provided.