ETSI TS 129 172 V12.6.0 (2020-01)

Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; Location Services (LCS); Evolved Packet Core (EPC) LCS Protocol (ELP) between the Gateway Mobile Location Centre (GMLC) and the Mobile Management Entity (MME); SLg interface (3GPP TS 29.172 version 12.6.0 Release 12)

RTS/TSGC-0429172vc60

General Information

• Status: Published
• Publication Date: 14-Jan-2020
• Technical Committee: 3GPP CT 4 - MAP/CAMEL/GTP/BCH/SS/TrFO/IMS/GUP/WLAN (formely CN4)
• Current Stage: 12 - Completion
• Completion Date: 15-Jan-2020

Standards Content (Sample)

ETSI TS 129 172 V12.6.0 (2020-01)






TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
Location Services (LCS);
Evolved Packet Core (EPC) LCS Protocol (ELP)
between the Gateway Mobile Location Centre (GMLC)
and the Mobile Management Entity (MME);
SLg interface
(3GPP TS 29.172 version 12.6.0 Release 12)

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3GPP TS 29.172 version 12.6.0 Release 12 1 ETSI TS 129 172 V12.6.0 (2020-01)



Reference
RTS/TSGC-0429172vc60
Keywords
GSM,LTE,UMTS
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3GPP TS 29.172 version 12.6.0 Release 12 2 ETSI TS 129 172 V12.6.0 (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).
The present document may refer to technical specifications or reports using their 3GPP identities. These shall be
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"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TS 29.172 version 12.6.0 Release 12 3 ETSI TS 129 172 V12.6.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 5
1 Scope . 6
2 References . 6
3 Definitions, symbols and abbreviations . 7
3.1 Definitions . 7
3.2 Symbols . 7
3.3 Abbreviations . 7
4 Functional Overview . 8
4.1 General . 8
5 ELP Message Transport . 9
5.1 General . 9
5.2 Use of Diameter base protocol . 9
5.3 Securing Diameter Messages . 9
5.4 Accounting functionality . 9
5.5 Use of sessions . 9
5.6 Transport protocol . 10
5.7 Routing considerations . 10
5.8 Advertising Application Support . 10
6 ELP Procedures . 10
6.1 General . 10
6.2 Provide Subscriber Location . 11
6.2.1 General . 11
6.2.2 Successful Operation . 11
6.2.3 Unsuccessful Operation . 18
6.3 Subscriber Location Report . 18
6.3.1 General . 18
6.3.2 Successful Operation . 18
6.3.3 Unsuccessful Operation . 22
7 ELP Messages and Message Formats . 22
7.1 General . 22
7.2 Message Formats . 23
7.3 ELP Messages . 23
7.3.1 Provide-Location-Request (PLR) Command . 23
7.3.2 Provide-Location-Answer (PLA) Command . 24
7.3.3 Location-Report-Request (LRR) Command . 24
7.3.4 Location-Report-Answer (LRA) Command . 25
7.4 Information Elements . 26
7.4.1 General . 26
7.4.2 SLg-Location-Type . 29
7.4.3 LCS-EPS-Client-Name . 29
7.4.4 LCS-Requestor-Name . 29
7.4.5 LCS-Priority . 30
7.4.6 LCS-QoS . 30
7.4.7 Horizontal-Accuracy . 30
7.4.8 Vertical-Accuracy . 30
7.4.9 Vertical-Requested. 30
7.4.10 Velocity-Requested . 30
7.4.11 Response-Time . 31
7.4.12 Supported-GAD-Shapes . 31
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3GPP TS 29.172 version 12.6.0 Release 12 4 ETSI TS 129 172 V12.6.0 (2020-01)
7.4.13 LCS-Codeword . 31
7.4.14 LCS-Privacy-Check . 31
7.4.15 Accuracy-Fulfilment-Indicator . 31
7.4.16 Age-Of-Location-Estimate . 31
7.4.17 Velocity-Estimate . 32
7.4.18 EUTRAN-Positioning-Data . 32
7.4.19 ECGI . 32
7.4.20 Location-Event . 32
7.4.21 Pseudonym-Indicator . 32
7.4.22 LCS-Service-Type-ID . 32
7.4.23 LCS-Privacy-Check-Non-Session . 32
7.4.24 LCS-Privacy-Check-Session. 33
7.4.25 Feature-List-ID . 33
7.4.26 Feature-List . 33
7.4.27 LCS-QoS-Class . 33
7.4.28 Serving-Node . 33
7.4.29 GERAN-Positioning-Info . 33
7.4.30 GERAN-Positioning-Data . 33
7.4.31 GERAN-GANSS-Positioning-Data . 34
7.4.32 UTRAN-Positioning-Info . 34
7.4.33 UTRAN-Positioning-Data . 34
7.4.34 UTRAN-GANSS-Positioning-Data . 34
7.4.35 LRR-Flags. 34
7.4.37 LCS-Reference-Number . 35
7.4.38 Area-Event-Info . 35
7.4.39 Area-Definition . 35
7.4.40 Area . 35
7.4.41 Area-Type . 36
7.4.42 Area-Identification . 36
7.4.43 Occurrence-Info . 36
7.4.44 Interval-Time . 36
7.4.45 Periodic-LDR-Info . 36
7.4.46 Reporting-Amount . 36
7.4.47 Reporting-Interval . 37
7.4.48 Reporting-PLMN-List . 37
7.4.49 PLMN-ID-List . 37
7.4.54 Deferred-MT-LR-Data . 38
7.4.55 Termination-Cause. 38
7.4.57 ESMLC-Cell-Info . 39
7.4.58 Cell-Portion-ID . 39
7.4.59 1xRTT-RCID . 39
7.5 Result-Code AVP and Experimental-Result AVP Values . 40
7.5.1 General . 40
7.5.2 Success . 40
7.5.3 Permanent Failures . 40
7.5.3.1 DIAMETER_ERROR_USER_UNKNOWN (5001) . 40
7.5.3.2 DIAMETER_ERROR_UNAUTHORIZED_REQUESTING_NETWORK (5490) . 40
7.5.4 Transient Failures . 40
7.5.4.1 DIAMETER_ERROR_UNREACHABLE_USER (4221). 40
7.5.4.2 DIAMETER_ERROR_SUSPENDED_USER (4222) . 40
7.5.4.3 DIAMETER_ERROR_DETACHED_USER (4223) . 40
7.5.4.4 DIAMETER_ERROR_POSITIONING_DENIED (4224) . 40
7.5.4.5 DIAMETER_ERROR_POSITIONING_FAILED (4225) . 41
7.5.4.6 DIAMETER_ERROR_UNKNOWN_UNREACHABLE LCS_CLIENT (4226) . 41
Annex A (informative): Change history . 42
History . 43

ETSI

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3GPP TS 29.172 version 12.6.0 Release 12 5 ETSI TS 129 172 V12.6.0 (2020-01)
Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
ETSI

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3GPP TS 29.172 version 12.6.0 Release 12 6 ETSI TS 129 172 V12.6.0 (2020-01)
1 Scope
The present document specifies the procedures and information coding for the EPC LCS Protocol (ELP) that is needed
to support the location services in E-UTRAN, UTRAN and GERAN. The ELP message set is applicable to the SLg
interface between the MME and the GMLC and the Lgd interface between the SGSN and the GMLC. ELP is developed
in accordance to the general principles stated in 3GPP TS 23.271 [3].
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 23.271: "Functional stage 2 description of Location Services (LCS)".
[3] 3GPP TS 23.032: "Universal Geographical Area Description (GAD)".
[4] IETF RFC 3588: "Diameter Base Protocol".
[5] IETF RFC 2234: "Augmented BNF for syntax specifications".
[6] 3GPP TS 23.003: "Numbering, addressing and identification".
[7] 3GPP TS 29.171: "LCS Application Protocol (LCS-AP) between the MME and E-SMLC".
[8] 3GPP TS 29.274: "Evolved General Packet Radio Service (GPRS) Tunnelling Protocol for Control
plane (GTPv2-C)".
[9] Void
[10] 3GPP TS 32.299: "Charging management; Diameter charging applications".
[11] 3GPP TS 29.272: "Evolved Packet System; MME and SGSN Related Interfaces Based on
Diameter Protocol".
[12] 3GPP TS 29.329: "Sh Interface based on the Diameter protocol".
[13] 3GPP TS 33.210: "3G Security; Network Domain Security; IP Network Layer Security".
[14] IETF RFC 4960: "Stream Control Transmission Protocol".
[15] 3GPP TS 22.071: "Location Services (LCS); Service description".
[16] IETF RFC 5778: "Diameter Mobile IPv6: Support for Home Agent to Diameter Server
Interaction".
[17] 3GPP TS 29.229: "Cx and Dx Interfaces based on the Diameter protocol; protocol details".
[18] 3GPP TS 29.173: "Location Services; Diameter-based SLh interface for Control Plane LCS".
[19] 3GPP TS 29.002: "Mobile Application Part (MAP) specification".
[20] 3GPP TS 49.031: "Location Services (LCS) – Base Station System Application Part LCS
Extension – (BSSAP-LE)".
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3GPP TS 29.172 version 12.6.0 Release 12 7 ETSI TS 129 172 V12.6.0 (2020-01)
[21] 3GPP TS 25.413: "UTRAN Iu Interface RANAP signalling".
[22] 3GPP2 A.S0014-D v5.0: "Interoperability Specification (IOS) for cdma2000 Access Network
Interfaces – Part 4 (A1, A1p, A2, and A5 Interfaces) UTRAN Iu Interface RANAP signalling".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply. A
term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].
EPC-MO-LR: EPC Mobile Originating Location Request
EPC-MT-LR: EPC Mobile Terminating Location Request
EPC-NI-LR: EPC Network Induced Location Request
PS-MO-LR: Packet Switched Mobile Originating Location Request
PS-MT-LR: Packet Switched Mobile Terminating Location Request
PS-NI-LR: Packet Switched Network Induced Location Request
LCS: LoCation Services
LCS Client: software and/or hardware entity that interacts with a LCS Server (in this case, the GMLC) for the purpose
of obtaining location information for one or more Mobile Stations. LCS Clients subscribe to LCS in order to obtain
location information. LCS Clients may or may not interact with human users. The LCS Client is responsible for
formatting and presenting data and managing the user interface (dialogue). The LCS Client may reside in the Mobile
Station (UE).
LCS QoS: The QoS class determines the degree of adherence to the quality of service information as required by the
source of a location request.
Target: UE being positioned
3.2 Symbols
For the purposes of the present document, the following symbols apply:
SLg Interface between GMLC and MME
Lgd Interface between GMLC and SGSN
3.3 Abbreviations
For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply. An
abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
TR 21.905 [1].
GMLC Gateway Mobile Location Centre
EPC Enhanced Packet Core
IMEI International Mobile Equipment Identity
IMS IP Multimedia Subsystem
IMSI International Mobile Subscriber Identity
MME Mobility Management Entity
TTTP Transfer To Third Party
UE User Equipment, as defined in 3GPP TS 23.032 [3]
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3GPP TS 29.172 version 12.6.0 Release 12 8 ETSI TS 129 172 V12.6.0 (2020-01)
4 Functional Overview
4.1 General
This document defines the EPC LCS Protocol (ELP) used on the SLg interface between the GMLC and the MME and
on the Lgd interface between the GMLC and the SGSN in the Evolved Packet Core (EPC).
The location of the SLg interface within the LCS logical architecture is shown in Figure 4.1-1.
HSS
UE eNB MME GMLC LRF
SLg
E-SMLC
PSAP
Serving PDN
IMS
Gateway Gateway

Figure 4.1-1 SLg interface in the LCS Architecture
The location of the Lgd interface within the LCS logical architecture is shown in Figure 4.1-2.
HSS
RNC
GMLC
UE SGSN LRF
/BSS
Lgd
Serving PDN PSAP
IMS
Gateway Gateway

Figure 4.1-2 Lgd interface in the LCS Architecture
The high level functions of the ELP protocol are described in 3GPP TS 23.271 [2].
The main functions of the protocol are:
- To allow the GMLC to request position estimates for a particular target UE from the MME or SGSN in order to
support the EPC-MT-LR or PS-MT-LR positioning procedures. This is achieved using the Provide Subscriber
Location message;
- To allow the MME or SGSN to return a position estimate or an error report to the GMLC in response to a
Provide Subscriber Location request as part of an EPC-MT-LR or PS-MT-LR positioning procedure;
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3GPP TS 29.172 ver
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