7.4.1 Ordinary HHO (lur Interface and CELL_DCH State)
The following HHO flow is based on the lur interface when the UE is in the CELL_DCH state.
Ordinary HHO (lur Interface and CELL_DCH State)
Figure 1.1 Ordinary HHO flow (lur interface and CELL_DCH state)
Signaling Flow Analysis
The signaling flow proceeds as below:
The SRNC sends the Radio Link Setup Request message to request radio
link setup.
The parameters include target RNC identity, s-RNTI, cell ID, TFS, and TFCS.
The target RNC allocates RNTI and radio resources for RRC connection
and radio links. In addition, it sends the NBAP message, namely, the Radio Link Setup Request message to the target NodeB.
The parameters include cell ID, TFS, TFCS, frequency, uplink scramble, power control, and so on.
The target NodeB allocates radio link resources, starts physical-layer
receiver, and sends the target NodeB the Radio Link Setup Response message. The parameters include signaling termination and transport layer addressing for lub data transmission and bearer.
The target RNC starts setting up lub data transmission and bearer
according to ALCAP protocol. The request contains that the AAL2 bound ID is for binding lub data transmission and bearer, as well as transport channel DCH. The NodeB confirms the request.
When the target RNC completes preparations, it sends SRNC the Radio
Link Setup Response message.
The SRNC starts setting up lub data transmission and bearer according to
ALCAP protocol. The request contains that the AAL2 bound ID is for binding lub data transmission and bearer, as well as transport channel DCH. The RNC confirms the request.
The SRNC send UE the Physical Channel Reconfiguration message. When the UE switches from using the original link to using the new one, the
original NodeB detects that the original link fails in synchronization. Then the original NodeB sends the NBAP message, namely, the Radio Link Failure Indication
message to the source RNC.
The SRNC sends the original SRNC the RNSAP message, namely, the
Radio Link Failure Indication.
When the UE completes setting up RRC connection with target RNC and
the related radio resources are allocated, the UE sends SRNC the RRC message, namely, the Physical Channel Reconfiguration Complete message.
The SRNC sends source RNC the RNSAP message, the Radio Link
Deletion Request message. This requires the RNC to release the corresponding resources used by original link.
The source RNC sends original NodeB the NBAP message, the Radio Link
Deletion Request message.
The parameters include cell ID and transport layer addressing information.
The source NodeB releases radio resources used by original link and sends
source RNC the NBAP message, the Radio Link Deletion Response message.
The source RNC starts releasing lur data transmission and bearer according
to the ALCAP protocol.
When the source RNC completes releasing lur data transmission and
bearer, it sends SRNC the RNSAP message, the Radio Link Deletion Response message.
The SRNC starts releasing lur data transmission and bearer according to
the ALCAP protocol. The request includes AAL2 bound ID for binding lur data transmission and bearer and the transport channel DCH. The release request is confirmed by the target RNC.
7.4.2 Inter-CN HHO Flow
Figure 1.1 Ordinary inter-CN HHO flow SGSN 2. Relocation Required RANAP RANAP RANAP RANAP 3. Relocation Request RANAP RANAP 9. Relocation Request Acknowledge
RANAP 1. Relocation Required RANAP
UE RNC
Source
RNC Target
MSC/SGSN
RANAP 4. Relocation Request RANAP
RANAP RANAP
10. Relocation Request Acknowledge
RANAP 11. Relocation Command RANAP
RANAP 12. Relocation Command RANAP
RANAP RANAP
14. Relocation Detect RRC
13. DCCH : Physical Channel Reconfiguration Note 1 RRC
5. ALCAP Iu Data Transport Bearer Setup Node B
Source
Node B Target
NBAP 6. Radio Link Setup Request NBAP
NBAP 7. Radio Link Setup Response NBAP
8. ALCAP Iub Data Transport Bearer Setup
RANAP RANAP
18. Relocation Complete RRC 17. DCCH : Physical Channel Reconfiguration Complete Note 1 RRC
RANAP 15. Relocation Detect RANAP
RANAP 19. Relocation Complete RANAP
RANAP 20. Iu Release Command RANAP NBAP 16. Radio Link Failure Indication NBAP
RANAP 21. Iu Release Command RANAP
22. ALCAP Iu Data Transport Bearer Release
RANAP 23. Iu Release Complete RANAP
RANAP 24. Iu Release Complete RANAP
SGSN/MSC
The ordinary inter-CN HHO flow proceeds as below:
or 2) The SRNC sends the Relocation required message to the nodes of the
source CN and the target CN.
or 4) After the CN makes necessary preparations, it sends the Relocation
Required message to the target RNC to allocating the corresponding resources.
The transmission and bearer at the lur interface is set up at the target RNC
and CN.
or 7) or 8) The target RNC allocates RNTI and radio resources for RRC
connection and radio links, and then sends target NodeB the NBAP message, the Radio Link Setup Request message. The target NodeB allocates radio link
resources starts physical layer receiver, and sends target RNC the NBAP message, the Radio Link Setup Response message.
The parameters include cell ID, TFS, TFCS, frequency, uplink scramble, power control, and so on.
or 10) When the RNC completes preparations, the RNC sends CN the
Relocation Required Acknowledge message.
or 12) The CN completes preparations and sends SRNC the Relocation
Command message.
The SRNC sends UE the RRC message, the Physical Channel
Reconfiguration message.
or 15) or 16) When the target RNC detects UE, it sends two nodes of CN
the Relocation Detect message. When the UE switches from using the original radio link to the new one, the source NodeB sends source RNC the Radio Link Failure Indication message upon detection of RL error by source NodeB.
When the UE completes setting up RRC connection with target RNC and
the corresponding radio resources are allocated, it sends target RNC the RRC message, the Physical Channel Reconfiguration Complete message.
or 19) After the UE succeeds in handing over to the target RNC and is
allocated with resources, the RNC sends all CNs the Relocation Complete message.
or 21) The CN sends SRNC the Lu Release Command message. The lu transmission and bearer between the original RNC and CN is
released.
or 24) The original RNC sends CN the Lu Release Complete message for