1、= 3404593 0078236 43T = Released: July 1, 1993 GSM 03.07 Version: 4.2.0 Date: 21 January, 1993 Work Item No: Key words: European digital cellular telecommunication system (phase 2); Restoration Procedures ETSI European Telecommunications Standards Institute ETSI Secretariat: Route des Lucioles. F -
2、06921 Sophia Antipolis Cedex . France TP. + 33 92 94 42 00 TF. + 33 93 65 47 16 Tx. 47 00 40 F This is an unpublished work the copyright in which vests in the European Telecommunications Standards Institute. All rights resewed. The information contained herein is the property of ETSI and no part may
3、 be reproduced or used except as authorised by contract or other written permission. The copyright and the foregoing restriction on reproduction and use extend to all media in which the information may be embodied. 3404583 0038217 336 Page 3 GSM 03.07 . version 4.2.0 : January 1993 CONTENTS 1 . INTR
4、ODUCTION 5 2 . DESIGN OBJECTIVES 6 3 . RESTORATION INDICATORS IN LOCATION REGISTERS . 6 3.1. Restoration Indicators in the VLR . 6 3.2. Restoration Indicators in the HLR 7 4 . RESTORATION OF DATA IN THE VLR . 8 4.1 . Restart of the VLR . 8 4.2. Restoration Procedures . 8 4.2.1. Incoming Call . 8 4.2
5、.2. Mobile Terminated Short Message . 10 4.2.3. Outgoing MS Request . 11 4.2.4. Location Updating or IMSI Attach . 12 4.2.5. Use of TMSI . 12 5 . RESTORATION OF DATA IN THE HLR . 14 5.1 . Restart of the HLR 14 5.2. Procedures During Restoration 14 5.2.1. Mobile terminated call . 14 5.2.2. Mobile Ori
6、ginated Activity . 14 6 . PERIODIC LOCATION UPDATING 15 7 . STAND-ALONE OPERATION OF THE VLR 15 Document history . 16 Previous page is blank W 3404583 0078218 202 Page 5 GSM 03.07 - version 4.2.0 : January 1993 1. INTRODUCTION The data stored in location registers are automatically updated in normal
7、 operation; the main information stored in a location register defines the location of each mobile station and the subscriber data required to handle traffic for each mobile subscriber. The loss or corruption of these data will seriousty degrade the service offered to mobile subscribers; it is there
8、fore necessary to define procedures to limit the effects of failure of a location register, and to restore the location register data automatically. This Technical Specification defines the necessary procedures. The basic principle is that restoration should be based on radio contact to avoid faulty
9、 data being spread in the system. Subscriber data for supplementary services must also be correctly restored, although the impact on service of corruption of supplementary service data is less severe. Procedures for supporting these functions are defined in Technical Specification GSM 09.02. The MAP
10、 operation IMSI Attach is used only in MAP version 1; in MAP version 2 the same function is performed by the MAP operation Update Location Area. References in this specification to IMSI attach apply only to MAP version 1 network entities. If the restoration of subscriber data in the VLR is triggered
11、 by Location Updating or IMSI Attach, the VLR retrieves subscriber data from the HLR by sending an Update Location request, which triggers one or more Insert Subscriber Data operations from the HLR. The Update Location request may also be used to send the LMSld to the HLR. If the restoration of subs
12、criber data in the VLR is triggered by a Provide Roaming Number request, the behaviour of the VLR depends on whether it is implemented according to MAP version 1 or MAP version 2. For MAP version 2, the VLR retrieves subscriber data from the HLR by sending a Restore Data request, which triggers one
13、or more Insert Subscriber Data operations from the HLR. The Restore Data request is also used to send the LMSld to the HLR. For MAP version 1, the VLR retrieves subscriber data from the HLR by sending a Send Parameters request with parameter type Subscriber Data, which cannot be used to send the LMS
14、Id to the HLR. The VLR number and MSC number in the subscriber data in the HLR are updated by the Update Location procedure. Previous page is blank rn 3404583 0078237 149 rn Page 6 GSM 03.07 - version 4.2.0 : January 1993 2. DESIGN OBJECTIVES To avoid loss of all the data stored in a location regist
15、er when part of the equipment of the location register fails, a regime must be implemented to secure the data. This regime can include replication of volatile storage units and periodic backup of data to non-volatile storage. If the data security regime ensures the integrity of the data in spite of
16、failure of part of the location register equipment then there will be no impact on service. This Technical Specification describes the procedures to be used when the integrity of data in the location register cannot be ensured; that situation is referred to below as failure. The VLR shall erase all
17、IMSI records affected by the failure when it restarts after a failure. For the HLR, periodic backup of data to non-volatile storage is mandatory. The reliability objectives of location registration are listed in Technical Specifications GSM 03.05 and GSM 12.07. 3. RESTORATION INDICATORS IN LOCATION
18、REGISTERS 3.1. Restoratlon Indicators In the MR Three restoration indicators are provided in the VLR for each IMSI record: Confirmed by Radio Contact, Confirmed by HLR and Location information Confirmed in HLR. The indicator Confirmed by Radio Contact indicates whether the VLRs record of location ar
19、ea identity and MSC number for the mobile station is confirmed by radio contact. The indicator Confirmed by Radio Contact in an IMSI record is set to Not Confirmed when the VLR receives a Provide Roaming Number request for an MS for which the VLR does not have an IMSI record. The indicator Confirmed
20、 by Radio Contact is set to Confirmed when the MS successfully establishes an authenticated radio contact. The indicator Confirmed by HLR indicates whether the subscriber data for the mobile station held by the VLR is consistent with that held by the HLR. The indicator Confirmed by HLR is set to Not
21、 Confirmed when the VLR receives a Provide Roaming Number request, an Update Location Area request or an IMSI Attach request for an MS for which me VLR does not have an IMSI record; W 3404583 0078220 960 = . Page 7 GSM 03.07 - verrlon 4.2.0 : January 1993 The indicator Confirmed by HLR is set to Con
22、firmed at either of the following events: The VLR successfully performs an Update Location to the HLR; The VLR successfully performs a Restore Data operation to the HLR. The indicator Location information Confirmed in HLR indicates whether the HLRs record of VLR number and MSC number for the mobile
23、station is confirmed by radio contact. The indicator Location Information Confirmed in HLR is set to Not Confirmed at either of the following events: A VLR which serves two or more MSCs receives a Provide Roaming Number request, an Update Location Area request or an IMSI Attach request for an MS for
24、 which the VLR has no IMSi record; The VLR receives a Reset message from the HLR with which the MS is registered. The indicator Location information Confirmed in HLR is set to Confirmed after successful completion of the Update Location procedure triggered by authenticated radio contact. 3.2. Restor
25、ation Indicators In tho HLR One restoration indicator is provided in the HLR for each IMSI record: Check SS. The Check SS indicator is set to Check Required when the HLR restarts after a failure. The Check SS indicator is checked whenever the HLR receives an Update Location request from a VLR. If it
26、 is set to Check Required, the HLR sends a Forward Check SS Indication to the VLR and sets the Check SS indicator to Check Not Required. = 3404583 0078223 AT7 Page 8 GSM 03.07 - version 4.2.0 : January 1993 4. RESTORATION OF DATA IN THE VLR The effect on service of failure of a VLR is different from
27、 the effect of failure of an HLR. The procedures for restoration of a VLR and an HLR are therefore different 4.1. Restart of tho MR When a VLR restarts after a failure, all IMSI records affected by the failure are erased. There will be no information stored for an affected mobile station until after
28、 either the VLR has received a Provide Roaming Number request for that mobile station or there has been a transaction originated by that mobile station. The VLR causes all affected TMSIs and all affected LMSlds to become invalid, Invalid in this context means that the TMSI and LMSld can no longer be
29、 regarded as aaccurate. The term is used to avoid unnecessary constraints on the implementation. The VLR then starts to handle requests for data from other mobile network entities, as described below. 4.2. Restoration Procodures The objective of the restoration procedure is to handle all traffic for
30、 each mobile subscriber correctly. In order to meet this objective, the procedure must make the subscriber data in the VLR consistent with that in the HLR, and make the location information in the HLR and VLR reflect accurateiy the current location of the MS. The VLR then starts to handle requests f
31、or data from other mobile network entities, as described below. 4.2.1. incoming Cali a) Send Routing information (GMSC-HLR) The HLR sends Provide Roaming Number to the VLR as for normal operation. The LMSld is updated by the VLR when the VLR requests the transfer of subscriber data from the HLR usin
32、g the Restore Data operation. = 3404583 0078222 733 rn Page 9 GSM 03.07 - vertlon 4.2.0 : January 1993 b) Provide Roaming Number (HLR-VLR) - Regardless of whether the VLR has an IMSI record corresponding to the IMSI in the Provide Roaming Number, it returns an MSRN. If no IMSI record exists, the VLR
33、 creates a skeleton IMSI record, sets the indicators Confirmed by Radio Contact and Confirmed by HLR to Not Confirmed and (if IMSI Attach is used) marks the IMSI as attached. If the VLR serves two or more MSCs, the VLR sets the indicator Location Information Confirmed in HLR to Not Confirmed. - If t
34、he indicator Confirmed by HLR is Not Confirmed the VLR requests subscriber data from the HLR. When the VLR has received the subscriber data from the HLR, the VLR sets the indicator Confirmed by HLR to Confirmed. The indicators Confirmed by Radio Contact and Location Information Information Confirmed
35、 in HLR remain unchanged. - If the IMSI record for the MS is marked Confirmed by HLR but Not Confirmed by Radio Contact the operator may choose an appropriate method to limit the number of Search for MS procedures for that MS. c) Send Information for I/C Call Setup (MSC-VLR) - If the VLR has no IMSI
36、 record, or if the record is marked Not Confirmed by HLR the VLR returns a System Failure error. - If the VLR has an IMSI record marked Confirmed by HLR and Not Confirmed by Radio Contact, the VLR handles the request in the normal way, except that the Search for MS procedure is used instead of the P
37、age MS procedure. - If the VLR has an IMSI record marked Confirmed by HLR and Confirmed by Radio Contact, the VLR handles the request in the normal way: for this MS, VLR restoration is complete. - The state of the indicator Location Information Confirmed in HLR does not affect the Send Information f
38、or I/C Call Setup procedure. d) Process Access Request in Response to Search (MSC-NLR) - If the MS responds to paging, the MSC sends a positive response to the search request and a Process Access Request to the VLR. The VLR sets the indicator Confirmed by Radio Contact to Confirmed, sets the locatio
39、n area information for the MS, and handles the request in the normal way. - The VLR checks the indicator Location Information Confirmed in HLR. If it indicates Not Confirmed the VLR starts an Update Location procedure to the HLR. When this procedure is successfully completed the VLR sets the indicat
40、or Location Information Confirmed in HLR to Confirmed. For this MS, VLR restoration is complete. 3404583 0078223 b7T Page 10 GSM 03.07 - version 4.2.0 : January 1993 4.2.2. Mobllo Terminated Short Message a) Send Routing Information for MT SMS (SMS-GMSC-HLR) The HLR returns the MSC number as for nor
41、mal operation. b) Send Information for MT SMS (MSC-VLR) - MAP version 2 - If the VLR has no IMSI record, or if the record is marked Not Confirmed by HLR the VLR returns an Unidentified Subscriber error. This causes the MSC to report a short message delivery failure, with cause Unidentified Subscribe
42、r, to the SMS gateway MSC. The Gateway MSC sends a Set Message Waiting Data request, with a cause of Absent Subscriber, to the HLR. This causes the HLR to set message waiting data for the MS, as described in Technical Specifications GSM 03.40 for this MS, VLR restoration is complete. - The state of
43、the indicator Location Information Confirmed in HLR does not affect the Send Information for MT SMS procedure. = 3404583 0078224 506 = Page 11 GSM 03.07 - version 4.2.0 : January 1993 d) Process Access Request in Response to Search (MSC-VLR) - If the MS responds to paging, the MSC sends a positive r
44、esponse to the search request and a Process Access Request to the VLR. The VLR sets the indicator Confirmed by Radio Contact to Confirmed, sets the location area information for the MS, and handles the request in the normal way. - The VLR checks the indicator Location Information Confirmed in HLR. I
45、f it indicates Not Confirmed the VLR starts an Update Location procedure to the HLR. When this procedure is successfuliy completed the VLR sets the indicator Location Information Confirmed in HLR to Confirmed. For this MS, VLR restoration is complete. 4.2.3. Outgolng MS Request An outgoing request (
46、MS originated call or call-independent supplementary service activity) from the MS causes the VLR to check its IMSI record for that MS. - If the MS is unknown in this VLR (.e. the VLR has no IMSI record for the MS) or there is an IMSI record marked Not Confirmed by HLR the outgoing request is reject
47、ed with error cause Unidentified Subscriber. This causes the MS to initiate the location registration procedure described below. - If the VLR has an IMSI record for the MS marked Confirmed by HLR the request is handled in the normal way, and after any necessary authentication and/or IMEI checking th
48、e record is marked Confirmed by Radio Contact. - The VLR checks the indicator Location Information Confirmed in HLR. If it indicates Not Confirmed the VLR starts an Update Location procedure to the HLR. When this procedure is successfully completed the VLR sets the indicator Location Information Con
49、firmed in HLR to Confirmed. For this MS, VLR restoration is complete. Page 12 GSM 03.07 - version 4.2.0 : January 1993 4.2.4. Locatlon Updatlng or IMSI Attach A location registration request (location updating or IMSI attach) from an MS causes the VLR to check its IMSI record for that MS. - If the MS is unknown in this VLR (.e. the VLR has no IMSI record for the MS) the
