7.1.3 Supporting UEs in a GWCN configuration

23.2513GPPArchitecture and functional descriptionNetwork sharingRelease 17TS

This example shows network selection for a supporting UE in a shared E‑UTRAN/UTRAN/GERAN network.

Figure 4: Network selection for a supporting UE in a shared E-UTRAN/UTRAN/GERAN network

1. The UE reads the broadcast system information in the shared RAN.

2. A supporting UE decodes the shared network information and supplies the available core network operator PLMN-ids as candidates to the PLMN selection procedure. Only PLMNs in the Multiple PLMN ID List are candidates for network selection.

3. The UE performs network selection among available PLMNs.

4. The UE sends an ATTACH/ROUTEING AREA UPDATE/TRACKING AREA UPDATE/LOCATION AREA UPDATE REQUEST message to the network indicating, to the RAN, the chosen core network operator. The RAN converts the core network ‘indicator’ into the actual selected PLMN identity and sends this with the ATTACH/ROUTEING AREA UPDATE/TRACKING AREA UPDATE/LOCATION AREA UPDATE REQUEST to the core network.

5. The shared SGSN determines whether the UE is allowed to attach.

6. The shared SGSN sends the appropriate ACCEPT/REJECT message back to the UE.