ETSI TS 123 271 V15.2.0 (2020-01)

ETSI TS 123 271 V15.2.0 (2020-01)






TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
Functional stage 2 description of Location Services (LCS)
(3GPP TS 23.271 version 15.2.0 Release 15)

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3GPP TS 23.271 version 15.2.0 Release 15 1 ETSI TS 123 271 V15.2.0 (2020-01)



Reference
RTS/TSGS-0223271vf20
Keywords
GSM,LTE,UMTS
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© ETSI 2020.
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DECT™, PLUGTESTS™, UMTS™ and the ETSI logo are trademarks of ETSI registered for the benefit of its Members.

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3GPP TS 23.271 version 15.2.0 Release 15 2 ETSI TS 123 271 V15.2.0 (2020-01)
Intellectual Property Rights
Essential patents
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pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
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Legal Notice
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
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Modal verbs terminology
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provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TS 23.271 version 15.2.0 Release 15 3 ETSI TS 123 271 V15.2.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 9
1 Scope . 10
2 References . 10
3 Definitions, symbols and abbreviations . 12
3.1 Definitions . 12
3.2 Symbols . 16
3.3 Abbreviations . 16
4 Main concepts . 20
4.1 Assumptions . 20
4.2 Location Services Categories . 21
4.3 Positioning methods . 21
4.3.1 Standard LCS Methods in UTRAN . 21
4.3.2 Standard LCS Methods in GERAN . 22
4.3.3 Standard LCS Methods in E-UTRAN . 22
4.4 Types of Location Request . 22
4.4.1 Immediate Location Request . 22
4.4.2 Deferred Location Request . 22
4.4.2.1 Types of event . 22
4.5 Concurrent Location Requests . 23
5 General LCS architecture . 24
5.1 LCS access interfaces . 24
5.2 LCS Functional diagram, high level functions . 25
5.3 LCS Client functional group . 26
5.3.1 External Location Client Function (LCF) . 26
5.4 LCS Server functional group . 26
5.4.1 Client handling component . 26
5.4.1.1 Location Client Control Function (LCCF) . 26
5.4.1.2 Location Client Authorization Function (LCAF) . 26
5.4.1.2.1 Access Subfunction . 26
5.4.1.2.2 Subscription Subfunction . 27
5.4.1.3 Location Client Co-ordinate Transformation Function (LCCTF) . 27
5.4.1.4 Location Client Zone Transformation Function (LCZTF) . 27
5.4.2 System handling component . 27
5.4.2.1 Location System Control Function(LSCF) . 27
5.4.2.2 Location System Billing Function (LSBF) . 28
5.4.2.3 Location System Operations Function (LSOF) . 28
5.4.2.4 Location System Broadcast Function (LSBcF) . 28
5.4.2.5 Location System Co-ordinate Transformation Function (LSCTF) . 28
5.4.2.6 Location IMS – Interworking Function (LIMS-IWF) . 28
5.4.3 Subscriber handling Component . 28
5.4.3.1 Location Subscriber Authorization Function (LSAF) . 28
5.4.3.2 Location Subscriber Translation Function (LSTF) . 28
5.4.3.3 Location Subscriber Privacy Function (LSPF). 28
5.4.4 Positioning components . 28
5.5 Information Flows between Client and Server . 29
5.5.1 Location Service Request . 29
5.5.2 Location Service Response . 30
5.6 Information Flows between LCS Servers . 31
5.6.1 Location Service Request . 31
5.6.2 Location Service Response . 33
ETSI

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3GPP TS 23.271 version 15.2.0 Release 15 4 ETSI TS 123 271 V15.2.0 (2020-01)
5.7 Optimized Lgd Procedure . 34
6 LCS Architecture . 34
6.0 Introduction . 34
6.1 Schematic functional description of LCS operations . 37
6.2 Allocation of LCS functions to network elements . 38
6.3 Functional description of LCS per network element . 41
6.3.1 Access Network . 41
6.3.2 LCS Clients, LCS applications and Requestors . 42
6.3.3 Gateway Mobile Location Centre, GMLC . 42
6.3.3A Location Retrieval Function, LRF . 43
6.3.4 LCS support in the UE . 43
6.3.5 MSC/VLR . 43
6.3.6 MSC Server . 43
6.3.7 SGSN . 44
6.3.8 Home Location Register, HLR . 44
6.3.9 HSS . 44
6.3.10 gsmSCF . 44
6.3.11 Privacy Profile Register, PPR . 44
6.3.12 Pseudonym Mediation Device, PMD. 44
6.3.13 Mobility Management Entity, MME . 44
6.3.14 Evolved Serving Mobile Location Centre, E-SMLC . 45
6.4 Addressing the target UE for LCS purposes . 45
6.4.1 Verinyms for the target UE . 45
6.4.2 Pseudonyms for the target UE . 45
6.4.3 Non-dialable callback numbers . 45
6.5 Quality of Service Information . 45
6.5.1 LCS QoS Class . 46
6.5.1.1 Best Effort Class . 46
6.5.1.2 Assured Class . 46
7 Signalling and Interfaces . 46
7.1 LCS signalling between Access and Core Networks for GERAN and UTRAN access networks . 46
7.1.1 Core network Location Request. 46
7.1.2 Location Report . 46
7.1a LCS signalling between Access and Core Networks for E-UTRAN access networks . 47
7.1a.1 Core network Measurement Request . 47
7.1a.2 Location Measurement Report . 47
7.2 Um, Uu and Uu-LTE Interfaces . 47
7.3 MAP Interfaces . 48
7.4 Lpp interface . 48
7.4.1 LCS Authorisation Request . 48
7.4.2 LCS Authorisation Response . 49
7.4.3 LCS Privacy Profile Update notification . 50
7.4.4 LCS Privacy Profile Update notification ack . 50
7.5 Lid interface . 50
7.5.1 LCS Identity Request . 50
7.5.2 LCS Identity Response . 50
7.6 IMS related Interfaces . 50
7.6.1 Dh Interface . 50
7.6.2 Sh Interface . 51
7.6.3 Ml Interface . 51
7.7 SLg Interface . 51
7.8 SLs Interface . 51
7.9 SLh Interface . 51
7.10 SLm Interface . 51
7.11 Lgd Interface . 51
8 General network location procedures . 51
8.1 State description for GMLC . 51
8.1.1 GMLC states . 51
8.1.1.1 NULL State . 51
8.1.1.2 INTERROGATION State . 52
ETSI

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3GPP TS 23.271 version 15.2.0 Release 15 5 ETSI TS 123 271 V15.2.0 (2020-01)
8.1.1.3 LOCATION State . 52
8.1.2 State functionality . 52
8.1.2.1 State Transitions . 52
8.1.2.2 INTERROGATION Timer Function . 53
8.1.2.3 LOCATION Timer Function . 53
8.2 State description for VMSC and MSC Server . 53
8.2.1 VMSC and MSC Server States . 53
8.2.1.1 LCS IDLE State . 53
8.2.1.2 LOCATION State . 53
8.2.2 State Functionality . 53
8.2.2.1 State Transitions . 53
8.2.2.2 LOCATION Timer Function . 54
8.3 LCS State description for SGSN . 54
8.3.1 SGSN States. 54
8.3.1.1 LCS IDLE State . 54
8.3.1.2 LOCATION State . 54
8.3.2 State Functionality . 54
8.3.2.1 State Transitions . 54
8.3.2.2 LOCATION Timer Function . 55
8.4 Signalling connection for the Iu interface . 55
8.5 Signalling connection for the A-interface . 55
8.6 Gb interface mapping of target UE. 55
8.7 LCS State description for MME . 55
8.7.1 MME States . 55
8.7.1.1 LCS IDLE State . 55
8.7.1.2 LOCATION State . 55
8.7.2 State Functionality . 56
8.7.2.1 State Transitions . 56
8.7.2.2 LOCATION Timer Function . 56
8.8 Signalling connection for the S1 interface . 56
9 General Network Positioning Procedures . 56
9.1 Mobile Terminating Location Request . 57
9.1.1 Common MT-LR procedure in PS and CS domain . 58
9.1.1A Common MT-LR procedure in PS and CS domain for Emergency MT-LR . 62
9.1.1.1 LCS Authorisation request . 64
9.1.1.2 LCS Privacy Profile Update . 65
9.1.1.3 LCS identity request . 65
9.1.2 Circuit Switched Mobile Terminating Location Request (CS-MT-LR) . 66
9.1.2.1 Location Preparation Procedure . 67
9.1.2.2 Positioning Measurement Establishment Procedure . 68
9.1.2.3 Location Calculation and Release Procedure . 68
9.1.3 CS-MT-LR without HLR Query . 68
9.1.4 CS-MT-LR and PS-MT-LR for a previously obtained location estimate . 69
9.1.4.1 Initial Location . 70
9.1.4.2 Current Location . 70
9.1.4.3 Last known Location .
...