11.2.3 Procedures in MSC/VLR

23.0933GPPRelease 17Stage 2Technical realization of Completion of Calls to Busy Subscriber (CCBS)TS

Figure 11.2.3.1: Procedure CCBS_MT_MSC_Check_Forwarding

This procedure is called to set the CCBS Target variable. That variable is used in later phase to set the correct diagnostic value to the Release message.

Figure 11.2.3.2: Procedure CCBS_Handle_PRN

This procedure is called to store CCBS call indicator when roaming number is reserved in the VLR.

Figure 11.2.3.3: Procedure CCBS_ICH_Set_CCBS_Call_Indicator

This procedure is called when VLR receives Send Info For Incoming Call message. If MSRN is related to the CCBS call, CCBS call indicator is set for call handling.

Figure 11.2.3.4: Procedure CCBS_ICH_MSC_Report_Failure

This procedure is called when CCBS call fails in the destination MSC and the reason is detected in the MSC side.

Figure 11.2.3.5: Procedure CCBS_ICH_VLR_Report_Failure

This procedure is called when CCBS call fails in the destination MSC and the reason is detected in the VLR side.

Figure 11.2.3.6: Procedure CCBS_ICH_Report_Not_Reachable

This procedure is called when call fails in the destination MSC with special cause of Not_Reachable. On normal call Not_Reachable message is sent to the monitoring process, on CCBS call subscriber is reported being absent.

Figure 11.2.3.7: Procedure CCBS_ICH_Handle_NDUB

This procedure is called when call encounters NDUB condition in the destination MSC. It is a network option to forward the call or release the call.

Figure 11.2.3.8: Procedure CCBS_ICH_Handle_UDUB

This procedure is called when call encounters UDUB condition in the destination MSC.

Figure 11.2.3.9: Procedure CCBS_ICH_MSC_Report_Success

This procedure is called when CCBS call is successfully delivered in the destination MSC and the event is detected in the MSC side.

Figure 11.2.3.10: Procedure CCBS_ICH_VLR_Report_Success

This procedure is called when CCBS call is successfully delivered in the destination MSC and the event is detected in the VLR side.

Figure 11.2.3.11: Procedure CCBS_ICH_Set_CCBS_Target

This procedure is called if when a call encounters busy condition in the destination MSC. If busy cause is NDUB and the user has elected to be target of CCBS requests, CCBS Target is set to True.

Figure 11.2.3.1: Procedure CCBS_MT_MSC_Check_Forwarding

Figure 11.2.3.2: Procedure CCBS_Handle_PRN

Figure 11.2.3.3: Procedure CCBS_ICH_Set_CCBS_Call_Indicator

Figure 11.2.3.4: Procedure CCBS_ICH_MSC_Report_Failure

Figure 11.2.3.5: Procedure CCBS_ICH_VLR_Report_Failure

Figure 11.2.3.6: Procedure CCBS_ICH_Report_Not_Reachable

Figure 11.2.3.7: Procedure CCBS_ICH_Handle_NDUB

Figure 11.2.3.8: Procedure CCBS_ICH_Handle_UDUB

Figure 11.2.3.9: Procedure CCBS_ICH_MSC_Report_Success

Figure 11.2.3.10: Procedure CCBS_ICH_VLR_Report_Success

Figure 11.2.3.11: Procedure CCBS_ICH_Set_CCBS_Target