The Application Controller (APPC, formerly abbreviated APP-C) manages and controls the life cycle of virtual applications, such as virtual network functions (VNFs), and their components.  APPC receives commands from internal ONAP components, such as SO, DCAE, or the Portal.

A virtual application is composed of the following layers of network technology:

A Life Cycle Management (LCM) command may affect one or more of these layers.

For example, a Terminate command applies to all four layers, whereas a Scale command may not apply to the VM layer.

An LCM command is sent as a request to the APPC using an HTTP POST request, or in a message on OpenECOMP's bus (DMaaP). For each request, the APPC returns one or more responses:

          An unauthorized or invalid request results in a single ERROR response.

For more information, see the APPC Documentation Repository