19.3.1 VLR fault recovery procedures
29.0023GPPMobile Application Part (MAP) specificationRelease 17TS
19.3.1.1 General
Restoration of an IMSI record in a VLR can be triggered by a location registration request from the MS or by a request from the HLR for a roaming number to route a mobile terminated call to the MS. If the restoration is triggered by a location registration request from the MS, the VLR performs the location updating procedure described in 3GPP TS 23.012 [23] and clause 19.1.1 of the present document. If the restoration is triggered by a request for a roaming number, the VLR provides the roaming number and triggers an independent dialogue to restore the subscriber data as described in 3GPP TS 23.018 [97]. The message flow for data restoration triggered by a request for a roaming number is shown in figure 19.3.1/1.
1) MAP_PROVIDE_ROAMING_NUMBER_req/ind
2) MAP_PROVIDE_ROAMING_NUMBER_rsp/cnf
3) MAP_SEND_AUTHENTICATION_INFO_req/ind (Note 1, note 2)
4) MAP_SEND_AUTHENTICATION_INFO_rsp/cnf (Note 1, note 2)
5) MAP_RESTORE_DATA_req/ind
6) MAP_ACTIVATE_TRACE_MODE_req/ind (Note 1, note 3)
7) MAP_ACTIVATE_TRACE_MODE_rsp/cnf (Note 1, note 3)
8) MAP_INSERT_SUBSCRIBER_DATA_req/ind
9) MAP_INSERT_SUBSCRIBER_DATA_rsp/cnf
10) MAP_RESTORE_DATA_rsp/cnf
NOTE 1: Services printed in italics are optional.
NOTE 2: If authentication is required.
NOTE 3: If subscriber tracing is active in the HLR.
Figure 19.3/1: Message flow for VLR restoration at mobile terminated call set-up
19.3.1.2 Procedure in the VLR
The procedure in the VLR to handle a dialogue for subscriber data restoration is defined in clause 21.2.6 of the present document.
19.3.1.3 Procedure in the HLR
The MAP process in the HLR to handle a request for data restoration in the VLR is shown in figure 19.3.1/2. The MAP process invokes macros not defined in this clause; the definitions of these macros can be found as follows:
Check_Indication see clause 25.2.1;
Control_Tracing_With_VLR_HLR see clause 25.9.6.
Figure 19.3.1/2: Process Restore_Data_HLR