The purpose of Service System Transition (SST) (CMMI-SVC) is to deploy new or significantly changed service system components while managing their effect on ongoing service delivery.
The Service System Transition process area addresses all aspects of planning, communicating, managing, deploying, and confirming that service system components effectively make the transition to the delivery environment. The scope of this process area covers both new components and significant changes to existing components. “Significant” is defined as a change that introduces unacceptable risk that the service system will not meet its objectives. Although these practices center on the transition of service system components, the transition of an entire service system (i.e., an interdependent and integrated collection of components) can also be managed using these practices. In this process area, the term “transition” refers to the comprehensive process of preparing for, executing, and confirming a deployment of service system components to a fully operational state while maintaining service delivery. The term “deploy” or “deployment” is more specific and refers to the activity of moving service system components into the delivery environment. In some domains, a deployment is also called a “roll-out.” Deployments generally fall into one of three categories:
- New installation
- Configuration control of service system components
- Management of internal and external interfaces
- Deployment of service system components into the delivery environment
- Stakeholder acceptance of new or revised service system components
- Management of impacts of the transition