GSM 09.02 - Version 5.3.0 - Digital cellular telecommunications - ETSI

16.3.3 VLR restoration: the restore data procedure in the HLR
Page 371
GSM 09.02 Version 5.3.0: August 1996
The MAP_RESTORE_DATA procedure in the HLR (Process RESTORE_DATA_HLR) is described in this
subclause; the corresponding procedure in the VLR (RESTORE_DATA_VLR) is described in
subclause 18.2.4.
The process RESTORE_DATA_HLR makes use of the following macros:
- Receive_Open_Ind subclause 21.1.1;
- Check_Indication subclause 21.2.1;
- Insert_Subs_Data_Framed_HLR subclause 16.4.1.
The MAP_RESTORE_DATA service is invoked by the VLR after provision of a roaming number in
response to a MAP_PROVIDE_ROAMING_NUMBER indication for an unidentified MS (i.e. IMSI unknown
in VLR), or for a known MS whose IMSI record is marked as "Not Confirmed" by the indicator "Confirmed
by HLR" (see 4 in figure 16.3/1). The process RESTORE_DATA_VLR is shown in figure 18.2/6.
The restore data process in the HLR is activated by receipt of a MAP_RESTORE_DATA indication from
the VLR (see figure 16.3/6). If there is a parameter problem in the indication, either of the errors
"Unexpected Data Value" or "Data Missing" is returned in the MAP_RESTORE_DATA response; if the
subscriber is not known in the HLR, the error "Unknown Subscriber" is returned in the
MAP_RESTORE_DATA response. In all of these cases the process in the HLR terminates.
If the MAP_RESTORE_DATA indication is accepted and if the LMSI is received, the HLR updates the
LMSI for the IMSI received in the MAP_RESTORE_DATA indication. For this IMSI the HLR sets
"subscriber-tracing-not-active-in-VLR" and checks whether tracing is required. This check is handled by the
macro "Control_Tracing_HLR" that is described in subclause 21.9. Thereafter, the macro
"Insert_Subs_Data_Framed_HLR" that is described in subclause 16.4.1 is invoked. The outcome of the
macro Insert_Subs_Data_Framed_HLR is one of:
- abort, in which case the process terminates;
- error, in which case the HLR returns the error "System Failure" in the MAP_RESTORE_DATA
response, and the process terminates;
- OK, indicating successful outcome of downloading the subscriber data to the VLR.
After successful completion of the framed MAP_INSERT_SUBSCRIBER_DATA procedure, the HLR
Number and, if applicable, the "MS Not Reachable Flag" which is used for SMS, are provided in the
MAP_RESTORE_DATA response.
Upon receipt of the MAP_RESTORE_DATA confirmation, the VLR behaves as described in
subclause 18.2.4, figure 18.2/6.