How it Works
This section describes how this feature works.
The Nchf_SpendingLimitControl service enables the NF service consumer to retrieve policy counter status information per UE from the CHF by subscribing to spending limit reporting (that is notifications of policy counter status changes).
If the spending limit reporting is no more required, the Nchf_SpendingLimitControl service enables the NF service consumer to unsubscribe from the reporting.
On receiving an N7 Create a Session request, if the N28 lookup or counter subscription is configured, PCF Engine triggers a session creation and subscription toward CHF. PCF then retrieves the counter information from the CHF response and generates virtual services for each counter which are used for making policy decisions.
If the errors or timeouts policy decisions continue without N28 counter information or policy (N7 response is success but excludes N28 based policy), then the N7 session and N28 session terminate.
The interface or model details for the N28 interface are provided in 3GPP TS29.594.