Content for TS 23.540 Word version: 18.3.0

1… 4… 5… 5.1.3 5.1.4 5.1.5 5.1.6 5.1.7… 5.1.7.2.3… 5.1.7.3.2 5.1.7.3.3 5.1.7.3.4 5.1.7.3.5 5.1.7.4 5.1.8… 5.2… 6…

5.1.7.3.5 SCP supports GPSI-to-Subscription-Network resolution with MNPF for Indirect routing
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5.1.7.3.5 SCP supports GPSI-to-Subscription-Network resolution with MNPF for Indirect routing p. 29

Figure 5.1.7.3.5-1 shows the procedure for Indirect Communication with Delegated Discovery, the SCP is the service consumer of the GPSI-to-Subscription-Network resolution service in MNPF NF and routes an SBI message based on GPSI when indirect routing of MNPF is implemented.

Copy of original 3GPP image for 3GPP TS 23.540, Fig. 5.1.7.3.5-1: SCP supports GPSI-to-Subscription-Network resolution with MNPF for Indirect routing

Figure 5.1.7.3.5-1: SCP supports GPSI-to-Subscription-Network resolution with MNPF for Indirect routing
(⇒ copy of original 3GPP image)

Step 1.

If the MNPF is deployed in the Number Range Holder PLMN, the MNPF registers in the NRF of the number range holder PLMN with a new NF Type (e.g. MNPF).

Step 2.

The SMS-GMSC sends Nudm_UECM_SendRoutingInfoForSM to the SCP to get the serving node instance for UE from the UDM. As specified in the Indirect Communication with Delegated Discovery model, the Nudm_UECM_SendRoutingInfoForSM shall contain the discovery factors containing the GPSI (pointing to the Number Range Holder Network) and an indicator that Subscription Network resolution is delegated to the SCP.

Step 3-4.

The SCP shall query the local NRF to find the MNPF instance that manages the PLMN ID of the recipients GPSI's subscription network, the local NRF forwards the discovery request to the NRF of the number range holder PLMN.

Step 5.

The SCP determines the target PLMN of the recipients GPSI's subscription network using the SBI service of the MNPF i.e. the SCP invokes Nmnpf_NPStatus_Get (GPSI) to the MNPF.

Step 6.

MNPF checks the portability status of the recipient GPSI and responds back with the target PLMN ID.

Step 7-8.

SCP shall query the local NRF to find the UDM instance serving the target PLMN based on target PLMN ID received in step 6.

For step 7a-8a, if the target PLMN ID belongs to the number range holder PLMN, the local NRF forwards the discovery request to the NRF of the number range holder PLMN.
For step 7b-8b, if the target PLMN ID belongs to the Subscription PLMN, the local NRF forwards the discovery request to the NRF of the Subscription PLMN.

Step 9-10.

SCP invokes Nudm_UECM_SendRoutingInfoForSM (GPSI) to the UDM of the target PLMN to get the serving node instance for UE. The UDM shall check the registration/reachability flags to determine the potential target nodes and responds to the SCP by sending Nudm_UECM_SendRoutingInfoForSM response, in this procedure the SMSF instance Id is included in the response message.

Step 11.

SCP forwards the responds to the SMS-GMSC by sending Nudm_UECM_SendRoutingInfoForSM response (SMS Router address).