5.11.2 Enhanced Relocation between HNB and RNC via HNB-GW

25.4673GPPRelease 17Stage 2TSUTRAN architecture for 3G Home Node B (HNB)

5.11.2.1 Enhanced Relocation from Open Access and Hybrid HNBs to RNC

The mobility procedure described in Figure 5.11.2.1-1 requires the HNB-GW to route the incoming Enhanced Relocation signalling from the Source HNB to the appropriate Target RNC indicated by an RNC-ID provided within the RNA:CONNECT message.

Figure 5.11.2.1-1: Enhanced Relocation from Open Access and Hybrid HNBs to RNC.

0-9. The RNSAP signalling for preparing and executing the relocation between the HNB and the RNC follows the standardised Enhanced SRNS Relocation procedure as defined between two RNCs (see TS 23.060 [10]).

10-13. After the UE has completed RRC signalling for the relocation, the RANAP: ENHANCED RELOCATION COMPLETE REQUEST message is sent from the Target RNC to the MSC/SGSN. The MSC/SGSN replies with a RANAP: ENHANCED RELCOATION COMPLETE RESPONSE message. In case of CS domain, the target RNC sends RANAP Enhanced Relocation Complete Confirm message to the MSC after completion of UP initialization.

14-17. Subsequently the CN initiates Iu Release procedure to release the source-side Iu(h) resources.

5.11.2.2 Enhanced Relocation from RNC to Open Access HNBs for CSG UEs

The mobility procedure described in Figure 5.11.2.2-1 requires the following:

– The Source RNC is able to determine the target HNB and its Cell Access Mode based on UE measurements.

NOTE: It is assumed that the source RNC has a priori knowledge whether the target cell is an open mode cell or not, e.g., via the PSC range configured for open cells in this part of the network

– The HNB-GW is able to route the incoming Enhanced Relocation signalling from the Source RNC to the appropriate target HNB using the target cell identity provided in RNSAP: ENHANCED RELOCATION REQUEST.

Figure 5.11.2.2-1: Enhanced Relocation from RNC to Open Access HNB for CSG UEs.

0-9. The RNSAP signalling for preparing and executing the relocation between the RNC and the HNB follows the standardised Enhanced SRNS Relocation procedure as defined between two RNCs (see TS 23.060 [10]).

10-12. After the UE has completed RRC signalling for the relocation, the RANAP: ENHANCED RELOCATION COMPLETE REQUEST message is sent from target HNB to HNB GW (via Iuh) and forwarded from HNB GW to MSC/SGSN (via Iu).

13-14. After the reception of RANAP: ENHANCED RELOCATION COMPLETE REQUEST the MSC/SGSN replies with RANAP: ENHANCED RELOCATION COMPLETE RESPONSE. The HNB-GW forwards this message to the target HNB (via Iuh).

15-16. In case of CS domain, the target HNB sends RANAP Enhanced Relocation Complete Confirm message to the MSC after completion of UP initialization.

17-18. The MSC/SGSN mandates the RNC to release the former Iu resources.

5.11.2.3 Enhanced Relocation from RNC to Hybrid HNB for CSG UEs

The mobility procedure described in Figure 5.11.2.3-1 requires the following:

– The UE is CSG capable from Rel-9 onwards and SIB-reading capable.

– The Source RNC is able to determine the Cell Access Mode of the target HNB.

NOTE: It is assumed that the source RNC is able to initiate and interpret respective UE measurements and may in addition have an a priori knowledge whether the target cell is a hybrid cell, e.g., via the PSC range configured for hybrid cells in this part of the network.

– The HNB-GW is able to route the incoming Enhanced Relocation signalling from the Source RNC to the appropriate target HNB using the target cell identity provided in RNSAP: ENHANCED RELOCATION REQUEST.

Figure 5.11.2.3-1: Enhanced Relocation from RNC to Hybrid HNB for CSG UEs.

0-9. RNSAP Signalling for preparing and executing the relocation between the RNC and the HNB follows the currently standardised Enhanced SRNS Relocation procedure as defined between two RNCs (See TS 23.060 [10]).

10-11. Upon successful relocation preparation and RRC signalling completion, the UE is temporarily admitted in the target hybrid cell according to the access status declared by the UE and provided by the Source RNC to the Target HNB within the CSG Membership Status IE included in the RNSAP: ENHANCED RELOCATION REQUEST message. The UE may be admitted as its reported CSG membership status until the outcomes of membership verification are received from CN.

12-13. The RANAP: ENHANCED RELOCATION COMPLETE REQUEST message is sent from target HNB to HNB GW (via Iuh) and forwarded from HNB GW to MSC/SGSN (via Iu). The RANAP: ENHANCED RELOCATION COMPLETE REQUEST includes CSG ID IE and Cell Access Mode IE of the target cell.

14-16. After reception of RANAP: ENHANCED RELOCATION COMPLETE REQUEST the MSC/SGSN performs membership verification of the relocated UE according to CSG ID IE and Cell Access Mode IE received. The MSC/SGSN replies to the HNB GW with RANAP: ENHANCED RELOCATION COMPLETE RESPONSE containing the CSG Membership Status IE. The RANAP: ENHANCED RELOCATION COMPLETE RESPONSE message is forwarded from HNB GW to target HNB (via Iuh). The target HNB may apply the appropriate level of prioritisation to the UE according to the CSG Membership Status IE received.

17-18. In case of CS domain, the target HNB sends RANAP Enhanced Relocation Complete Confirm message to the MSC after completion of UP initialization.

19-20. The MSC/SGSN requests the RNC to release the source-side Iu resources.