A Controller manages the state of a single Resource (Application or Network). It executes the Resource's configuration and instantiation, and is the primary agent in ongoing management, such as control loop actions, migration, and scaling. All of these actions involve executing workflows obtained from Service Design and Creation (SDC). In addition, the Controller reports the status of each workflow execution to both the Active and Available Inventory (AAI) and the Master Service Orchestrator (MSO).
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Network Controllers
A Network Controller, such as instantiates a Virtual Network Function by carrying out its network configuration workflow and reporting the resulting status (to both AAI and MSO).
Application Controllers
The MSO sends requests to the Application Controllers to obtain the application-specific component of the Service workflow from SDC and to execute the orchestration workflowApplication controllers, such as APPC, receive orchestrated requests from the MSO, which obtains application-specific components and attributes from SDC. The MSO continues to be responsible for ensuring that the Application Controller successfully completes its Resource configuration as defined by the workflow.
Note that not all changes in network or service behavior are the result of orchestration. For example, Application Virtual Functions can change network behavior by changing rules or policies associated with Controller activities. These policy changes can dynamically Policies and rules (in the Policy subsystem) inform the controller such that the Controller can enable service behavior changes.
OpenECOMP includes a generic Application Controller (APP-C, sometimes called APPC) that receives commands from OpenECOMP components, such as MSO, DCAE, or the Portal, and uses these commands to manage the life cycle of Services, Resources (virtual applications and Virtual Network Functions), and their components. See the OpenECOMP Application Controller User Guide and the <<DocRef: Application Controller (APP-C) API Guide>>.