Cisco ASR 5000 Series - Page 184

ASN Gateway Overview
▀ ASN Call Procedure Flows
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
Figure 49. MS initiated Uncontrolled Intra-ASN Gateway Handover Preparation Phase
Serving
ASN BS
Anchor ASN-GW/
Authenticator
MN
Data Path Established
1
2
4
Target
ASN BS
6
5
3
R8_HO_Req_Timer
Mob_Msho-Req
HO-Req
HO-Rsp
Mob_Msho-Rsp
HO-Ack
Table 34. MS initiated Uncontrolled Intra-ASN Gateway Handover Preparation Phase Description
Step
Description
1
MS sends MOB_MSHO_REQ messages to serving BS
2
Upon receiving MS initiated handover request (MOB_MSHO_REQ), the serving BS sends HO_Req messages to target BS
selected by MS and starts R8_HO_Req timer
3
Targeted BS tests the acceptability of the requested HO by comparing the amount of available resources and required
bandwidth/QoS parameters in the HO request received from serving BS
4
Once a target BS accepts the request it sends the HO_Rsp message to the serving BS
5
Serving BS sends MOB_MSHO_RSP response t o MS
6
Serving BS sends HO_Ack message to the target BS and HO preparation phase is completed
HO Action Phase
The following figure and table describe the call flow for the steps involved in uncontrolled intra-ASN Gateway
handover action phase between two BSs.