Cisco ASR 5000 Series Administration Manual page 34

▀ How HNB-GW Works
Figure 8.
1. User session is established between UE and CN via HNB and HNB-GW over Iu interface and CN (SGSN/MSC)
starts RANAP Iu Release procedure with HNB-GW and sends SCCP-DATA-FORM1 REQ with RANAP Iu
Release command to HNB-GW.
2. The HNB-GW uses the information received in SCCP-DATA-FORM1 REQ with RANAP Iu Release procedure
from CN and forwards the same to HNB through RUA-DIRECT-TRANSFER message with RANAP Iu
Release command.
3. On reception of RANAP Iu Release command in RUA-DIRECT-TRANSFER message the HNB triggers the
RCC Connection Release procedure and responds to HNB-GW with RANAP Iu Release Complete command
in RUA-DISCONNECT Response message.
▄ Cisco ASR 5000 Series 3G Home NodeB Gateway Administration Guide
Network Initiated Iu Connection Release Call Flow
HNB Gateway in UMTS Network
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