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The sequence diagram below shows the actions of the PDP at startup. See also Section 4 of the Policy Design and API Flow for Model Driven Control Loop - Draft page for the API used to implement this sequence.
At startup, the PDP initializes itself. At this point it is in PASSIVE mode. The PDP begins sending periodic Status messages to the PAP.
The first Status message initializes the process of loading the correct Policy Set on the PDP in the PAP (see Section 2.2.5.1).
On receipt or a shutdown request, the PDP completes or aborts any ongoing policy executions and shuts down gracefully.
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