4.18 Procedures for Management of PFDs

23.5023GPPProcedures for the 5G System (5GS)Release 18TS

4.18.1 General

NOTE: The PFDF service is functionality within the NEF.

4.18.2 PFD management via NEF (PFDF)

Figure 4.18.2-1 procedure for PFD management via NEF (PFDF)

1. The AF invokes the Nnef_PFDManagement_Create/Update/Delete service. The Allowed Delay is an optional parameter. If the Allowed Delay is included, it indicates that the list of PFDs in this request should be provisioned within the time interval indicated by the Allowed Delay to the SMF(s) that have subscribed to the PFD management service using Nnef_PFDManagement_Subscribe service operation.

2. NEF checks whether the AF is authorized to perform this request and NEF (PFDF) checks if the AF is authorised to provision this PFD data based on the operator policies.

3. The NEF (PFDF) invokes the Nudr_DM_Create/Update/Delete (Application Identifier, one or more sets of PFDs, Allowed Delay) to the UDR.

4. The UDR updates the list of PFDs for the Application Identifier.

5. The UDR sends a Nudr_DM_Create/Update/Delete Response to the NEF (PFDF).

6. The NEF sends Nnef_PFDManagement_Create/Update/Delete Response to the Application Function.

4.18.3 PFD management in the SMF

4.18.3.1 PFD Retrieval by the SMF

This procedure enables the SMF to retrieve PFDs for an Application Identifier from the NEF (PFDF) when a PCC rule with this Application Identifier is provided/activated and PFDs provided by the NEF (PFDF) are not available at the SMF.

In addition, this procedure enables the SMF to retrieve PFDs from the NEF (PFDF)when the caching timer for an Application Identifier elapses and a PCC Rule for this Application Identifier is still active.

The NEF (PFDF) retrieves the PFDs from UDR unless already available in NEF (PFDF).

The SMF may retrieve PFDs for one or more Application Identifiers in the same Request. All PFDs related to an Application Identifier are provided in the response from the UDR to NEF (PFDF).

Figure 4.18.3.1-1 PFD Retrieval by the SMF

1. SMF invokes the Nnef_PFDManagement_Fetch (Application Identifier (s)) to the NEF (PFDF).

2. NEF (PFDF) checks if the PFDs for the Application Identifier (s) are available in the NEF (PFDF), if available, the NEF (PFDF) skips to step 4. If not, the NEF (PFDF) invokes Nudr_DM_Query (Application Identifier (s)) to retrieve the PFD(s) from UDR.

3. The UDR provides a Nudr_DM_Query response (Application Identifier(s), PFD(s)) to the NEF (PFDF).

4. The NEF (PFDF) replies to the SMF with Nnef_PFDManagement_Fetch (Application Identifier(s), PFD(s)).

4.18.3.2 Management of PFDs in the SMF

This procedure enables the provisioning, modification or removal of PFDs associated with an application identifier in the SMF. Either the complete list of all PFDs of all application identifiers, the complete list of all PFDs of one or more application identifiers or a subset of PFDs for individual application identifiers may be managed.

Each PFD of an application identifier is associated with a PFD id if a subset of the PFD(s) associated with an application identifier can be provisioned, updated or removed. If always the full set of PFD(s) for an application identifier is managed in each transaction, PFD ids do not need to be provided.

Figure 4.18.3.2-1 Management of PFDs in the SMF

1. As pre-requisite condition to receiving push notifications, the SMF subscribes to PFD notifications from the NEF (PFDF) by sending Nnef_PFDManagement_Subscribe message.

2. The NEF (PFDF) invokes Nnef_PFD_Management_Notify (Application Identifier, PFDs, PFDs operation) to the SMF(s) to which the PFD(s) shall be provided. The NEF (PFDF) may decide to delay the distribution of PFDs to the SMF(s) for some time to optimize the signalling load. If the NEF (PFDF) received an Allowed Delay for a PFD, the NEF (PFDF) shall distribute this PFD within the indicated time interval.