7.3.2 Functional requirements of VLR
23.0183GPPBasic call handlingRelease 17Technical realizationTS
7.3.2.1 Process ICH_VLR
Sheet 1: if the MSRN received in the Send Info For Incoming Call is not allocated or there is no IMSI record for the IMSI identified by the MSRN or the MS is marked as "Subscriber data dormant" (e.g. due to super-charger), this is treated as an unknown MSRN.
Sheet 1: MT roaming retry is not triggered for an incoming call that arrives at the old VLR after the receipt of the MAP Send Identification request from the new VLR but before the receipt of the MAP Cancel Location from the HLR. The "Cancel Location received" flag enables to differentiate for a subscriber whose subscriber data is dormant whether a Cancel Location has been received or not from the HLR.
Sheet 1: the procedure CAMEL_ICH_VLR is specific to CAMEL phase 3 or later; it is specified in 3GPP TS 23.078 [12]. If the VLR does not support CAMEL phase 3 or later, processing continues from the possible call of the procedure CCBS_ICH_Set_CCBS_Call_Indicator. .
Sheet 1: If the MSRN is not allocated, "GMSC supports MT Roaming Retry" takes "No" exit.
Sheet 1: If no IMSI record is found, the " Subscriber data dormant" check takes the "False" exit.
Sheet 1: A VLR not supporting the flag "Subscriber data dormant" shall behave as if the flag is set to false.
Sheet 1: the procedure CCBS_ICH_Set_CCBS_Call_Indicator is specific to CCBS; it is specified in 3GPP TS 23.093 [23].
Sheet 1: the VLR derives the basic service required for the call according to the rules defined in 3GPP TS 29.007 [30].
Sheet 1, sheet 2, sheet 5: the procedure CCBS_ICH_VLR_Report_Failure is specific to CCBS; it is specified in 3GPP TS 23.093 [23].
Sheet 1, sheet 3: the procedure CCBS_ICH_Report_Not_Reachable is specific to CCBS; it is specified in 3GPP TS 23.093 [23].
Sheet 2: this process communicates with the matching instance of the process PRN_VLR, which is linked by the MSRN.
Sheet 2: the test "Paging via SGSN possible" takes the "yes" exit if:
– the Gs interface is implemented; and
– there is an association established for the MS between the MSC/VLR and the SGSN.
Sheet 3: the test "NDUB?" takes the "Yes" exit if the Page MS negative response or the Search for MS negative response had the value Busy Subscriber (NDUB).
Sheet 3: the procedure Get_CW_Subscription_Info_VLR is specific to Call Waiting. If the VLR does not support Call Waiting, processing continues from the "No" exit of the test "CW available?".
Sheet 3: the procedure Get_CW_Subscription_Info_Multicall_VLR is specific to Multicall; it is specified in 3GPP TS 23.135 [34]. If the VLR does not support both Multicall and Call Waiting, processing continues from the "No" exit of the test "CW available?".
Sheet 3: the VLR uses the basic service returned in the Page MS negative response or the Search for MS negative response Busy Subscriber (More calls possible) to determine whether call waiting is available.
Sheet 3: the procedure Get_LI_Subscription_Info_MT_VLR is specific to CLIP and COLR. If the VLR supports neither CLIP nor COLR, the procedure call is omitted.
Sheet3: the procedure Get_AoC_Subscription_Info_VLR is specific to AoC; it is specified in clause 7.1.2.15.
Sheet 3 sheet 6: the procedure CLI_ICH_VLR_Add_CLI is specific to Enhanced CLI Handling. It is specified in 3GPP TS 23.081 [14].
Sheet 3: the procedure CCBS_ICH_Handle_NDUB is specific to CCBS; it is specified in 3GPP TS 23.093 [23]. If the VLR does not support CCBS, processing continues from the "Forward" exit of the test "Result".
Sheet 3: the procedure Process_Access_Request_VLR is specified in clause 7.1.2.2.
Sheet 3: the output signal Page MS towards the SGSN includes the Location area identity parameter.
Sheet 3: if the VLR does not support CUG, handling continues from the "No" exit of the test "CUG info present?".
Sheet 3: the "MT Roaming Forwarding Supported" check takes the "Yes" exit if both the MSC and the VLR support that feature. If both the MT Roaming Retry and the MT Roaming Forwarding procedures are supported, and if the conditions for using these procedures are met, the VLR can decide based on operator policy which procedure to follow.
Sheet 3: MT Roaming Forwarding is possible towards the new VLR if the conditions defined in clause 5.2.3 are fulfilled. If so, the old VLR sends a MAP Provide Roaming Number request to the new VLR whose address was received in the MAP Cancel Location message or the MAP Send Identification message. In addition to the requirements specified in clause 10.2.3 of 3GPP TS 29.002 [29], the MAP Provide Roaming Number request shall not include the "OR Interrogation" parameter when being sent as part of the MT Roaming Forwarding call after successful retrieval of routeing information procedure.
Sheet 4, sheet 6: the procedure CAMEL_CHECK_SII2_CDTI is specific to CAMEL Phase 3 or later; it is specified in 3GPP TS 23.078 [12]. If the GMSC does not support CAMEL Phase 3 or later, processing continues from the "Yes" exit of the test "Result = Pass?".
Sheet 5, sheet 6: the procedure CD_Authorization is specific to Call Deflection, it is specified in 3GPP TS 23.072 [11]. If the VLR does not support Call Deflection, processing continues from the "Yes" exit of the test "Result=Aborted?".
Sheet 5, sheet 6: the procedure CCBS_ICH_Handle_UDUB is specific to CCBS; it is specified in 3GPP TS 23.093 [23].
Sheet 6: the test "NDUB?" is executed only if the VLR supports CCBS. If the VLR does not support CCBS, processing continues from connector 5.
Sheet 7: the procedure CCBS_ICH_Set_CCBS_Target is specific to CCBS; it is specified in 3GPP TS 23.093 [23].
Sheet 7: the procedure Handle_CFNRc is specified in clause 7.2.2.11.
Sheet 8: the procedure Forward_CUG_Check is specific to CUG; it is specified in clause 7.2.2.6. If the VLR does not support CUG, processing continues from the "Yes" exit of the test "Result=Call allowed?".
Sheet 8: the procedures CAMEL_O_CSI_Check_VLR, and CAMEL_D_CSI_Check_VLR are specific to CAMEL phase 3 or later; they are specified in 3GPP TS 23.078 [12].
7.3.2.2 Void
7.3.2.3 Procedure Search_For_MS_VLR
The test "Paging via SGSN possible" takes the "yes" exit if:
– the Gs interface is implemented; and
– the VLR configuration requires paging via the SGSN during VLR restoration.
The output signal Page MS towards the SGSN omits the Location area identity parameter. It is sent to every SGSN to which the VLR is connected.
7.3.2.4 Procedure Get_CW_Subscription_Info_VLR
The VMSC may abort the transaction with the VLR while a response is awaited from the process MAF013. The message is saved for processing after return from the procedure.
7.3.2.5 Procedure Get_LI_Subscription_Info_MT_VLR
The VMSC may abort the transaction with the VLR while a response is awaited from the process CLIP_MAF001 or the process COLR_MAF040. The message is saved for processing after return from the procedure.
7.3.2.6 Procedure Handle_CFB
The test "Normal call busy" refers to the value of the indicator returned by the process MAF008.
The procedure CAMEL_CHECK_SII2_CDTI is specific to CAMEL Phase 3 or later; it is specified in 3GPP TS 23.078 [12]. If the GMSC does not support CAMEL Phase 3 or later, processing continues from the "Yes" exit of the test "Result = Pass?".
7.3.2.7 Procedure Handle_CFNRy
The test "Normal call" refers to the value of the indicator returned by the process MAF009.
Figure 76a: Process ICH_VLR (sheet 1)
Figure 76b: Process ICH_VLR (sheet 2)
Figure 76c: Process ICH_VLR (sheet 3)
Figure 76d: Process ICH_VLR (sheet 4)
Figure 76e: Process ICH_VLR (sheet 5)
Figure 76f: Process ICH_VLR (sheet 6)
Figure 76g: Process ICH_VLR (sheet 7)
Figure 76h: Process ICH_VLR (sheet 8)
Figure 77: Void
Figure 78: Procedure Search_For_MS_VLR
Figure 79: Procedure Get_CW_Subscription_Info_VLR
Figure 80: Procedure Get_LI_Subscription_Info_MT_VLR
Figure 81: Procedure Handle_CFB
Figure 82: Procedure Handle_CFNRy