ETSI TS 129 172 V13.2.0 (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 13.2.0 Release 13)

3GPP TS 29.172 version 13.2.0 Release 13 1 ETSI TS 129 172 V13.2.0 (2020-01)

Reference
RTS/TSGC-0429172vd20
Keywords
GSM,LTE,UMTS
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3GPP TS 29.172 version 13.2.0 Release 13 2 ETSI TS 129 172 V13.2.0 (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
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
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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
interpreted as being references to the corresponding ETSI deliverables.
The cross reference between 3GPP and ETSI identities can be found under http://webapp.etsi.org/key/queryform.asp.
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
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3GPP TS 29.172 version 13.2.0 Release 13 3 ETSI TS 129 172 V13.2.0 (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 . 30
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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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 . 32
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 . 33
7.4.23 LCS-Privacy-Check-Non-Session . 33
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 . 34
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 . 36
7.4.40 Area . 36
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 . 37
7.4.46 Reporting-Amount . 37
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 . 39
7.4.55 Termination-Cause. 39
7.4.57 ESMLC-Cell-Info . 40
7.4.58 Cell-Portion-ID . 40
7.4.59 1xRTT-RCID . 40
7.4.60 Delayed-Location-Reporting-Data. 40
7.4.61 Civic-Address . 41
7.4.62 Barometric-Pressure. 41
7.4.63 UTRAN-Additional-Positioning-Data . 41
7.5 Result-Code AVP and Experimental-Result AVP Values . 41
7.5.1 General . 41
7.5.2 Success . 41
7.5.3 Permanent Failures . 41
7.5.3.1 DIAMETER_ERROR_USER_UNKNOWN (5001) . 41
7.5.3.2 DIAMETER_ERROR_UNAUTHORIZED_REQUESTING_NETWORK (5490) . 41
7.5.4 Transient Failures . 41
7.5.4.1 DIAMETER_ERROR_UNREACHABLE_USER (4221). 42
7.5.4.2 DIAMETER_ERROR_SUSPENDED_USER (4222) . 42
7.5.4.3 DIAMETER_ERROR_DETACHED_USER (4223) . 42
7.5.4.4 DIAMETER_ERROR_POSITIONING_DENIED (4224) . 42
7.5.4.5 DIAMETER_ERROR_POSITIONING_FAILED (4225) . 42
7.5.4.6 DIAMETER_ERROR_UNKNOWN_UNREACHABLE LCS_CLIENT (4226) . 42
Annex A (informative): Change history . 43
History . 44
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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.
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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 [2].
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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[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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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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- To allow the MME to forward an unsolicited position estimate to the GMLC as part of the EPC-MO-LR or EPC-
NI-LR procedures. This is achieved using the Subscriber Location Report message;
- To allow the SGSN to forward an unsolicited position estimate to the GMLC as part of the PS-MO-LR, PS-NI-
LR or periodic MO-LR TTTP procedures. This is achieved using the Subscriber Location Report message;
- To allow the GMLC to acknowledge receipt of an unsolicited position estimate as part of the EPC-MO-LR,
EPC-NI-LR, PS-MO-LR, PS-NI-LR or periodic MO-LR TTTP procedures;
- To allow the GMLC to request position estimates for a particular target UE from the SGSN as part of the
deferred MT-LR procedure. This is achieved using the Provide Subscriber Location message;
NOTE: The deferred MT-LR procedure is not applicable to MME in this version of the TS.
- To allow the SGSN to to acknowledge receipt of position estimate request to the GMLC as part of a deferred
MT-LR procedure;
- To support the procedures for handover of an IMS emergency call with EPS/GPRS access.
5 ELP Message Transport
5.1 General
The ELP protocol is defined as a Vendor Specific diameter application (SLg application). It reuses the basic
mechanisms defined by the diameter base protocol, and it defines a number of additional commands and AVPs to
implement the SLg, Lgd specific procedures.
5.2 Use of Diameter base protocol
The Diameter Base Protocol as specified in IETF RFC 3588 [4] shall apply except as modified by the defined support
of the methods and the defined support of the commands and AVPs, result and error codes as described in this
specification. Unless otherwise specified, the procedures (including error handling and unrecognised information
handling) shall be used unmodified.
5.3 Securing Diameter Messages
For secure transport of Diameter messages, see 3GPP TS 33.210 [13].
5.4 Accounting functionality
Accounting functionality (Accounting Session State Machine, related command codes and AVPs) shall not be used on
the SLg, Lgd interfaces.
5.5 Use of sessions
Between the MME and the GMLC and between the SGSN and the GMLC, Diameter sessions shall be implicitly
terminated. An implicitly terminated session is one for which the server does not maintain state information. The client
shall not send any re-authorization or session termination requests to the server.
The Diameter base protocol includes the Auth-Session-State AVP as the mechanism for the implementation of
implicitly terminated sessions.
The client (server) shall include in its requests (responses) the Auth-Session-State AVP set to the value
NO_STATE_MAINTAINED (1), as described in IETF RFC 3588 [4]. As a consequence, the server shall not maintain
any state information about this session and the client shall not send any session termination request. Neither the
Authorization-Lifetime AVP nor the Session-Timeout AVP shall be present in requests or responses.
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5.6 Transport protocol
Diameter messages over the SLg and Lgd interfaces shall make use of SCTP (see IETF RFC 4960 [14]).
5.7 Routing considerations
This clause specifies the use of the Diameter routing AVPs Destination-Realm and Destination-Host.
Destination-Realm AVP shall always be included in all diameter requests, and therefore is declared as mandatory in the
ABNF for all commands.
When a request is initiated by the GMLC, the name of the MME or SGSN shall be determined by querying the HSS
over the SLh interface, and retrieve the specific MME or SGSN that is currently serving the UE. Therefore, Destination-
Host AVP shall always be included in the commands originated at the GMLC, and is declared as mandatory in the
ABNF.
When a request is initiated by the MME or SGSN, the name of the GMLC may be either locally configured in the
MME/SGSN (e.g., in the intra-domain scenario, when the GMLC belongs to the same PLMN as the MME/SGSN), or it
is known from a previously received location procedure initiated at the GMLC. Therefore, the Destination-Host AVP is
declared as mandatory in the ABNF of the commands originated at the MME or SGSN.
If the Vendor-Specific-Application-ID AVP is received in any of the commands, it may be ignored by the receiving
node, and it shall not be used for routing purposes.
5.8 Advertising Application Support
The MME, SGSN and GMLC shall advertise support of the Diameter SLg Application by including the value of the
application identifier in the Auth-Application-Id AVP within the Vendor-Specific-Application-Id grouped AVP of the
Capabilities-Exchange-Request and Capabilities-Exchange-Answer commands.
The vendor identifier value of 3GPP (10415) shall be included in the Supported-Vendor-Id AVP of the Capabilities-
Exchange-Request and Capabilities-Exchange-Answer commands, and in the Vendor-Id AVP within the Vendor-
Specific-Application-Id grouped AVP of the Capabilities-Exchange-Request and Capabilities-Exchange-Answer
commands.
The Vendor-Id AVP included in Capabilities-Exchange-Request and Capabilities-Exchange-Answer commands that is
not included in the Vendor-Specific-Application-Id AVPs as described above shall indicate the manufacturer of the
Diameter node as per RFC 3588 [4].
6 ELP Procedures
6.1 General
The ELP procedures, between the GMLC and the MME over SLg interface and between GMLC and SGSN over Lgd
interface, are used to exchange messages related to location services. The ELP can be divided into the following sub-
procedures.
- Provide Subscriber Location
- Subscriber Location Report
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6.2 Provide Subscriber Location
6.2.1 General
The Provide Subscriber Location operation is used by a GMLC to request the location of a target UE from the MME or
SGSN at any time, as part of EPC-MT-LR or PS-MT-LR positioning procedures. The response contains a location
estimate of the target UE and other additional information.
The Provide Subscriber Location operation is also used by a GMLC to request the location of the target UE from the
SGSN at any time, as part of deferred MT-LR procedure. The response contains the acknowledgment of the receipt of
the request and other additional information.
6.2.2 Successful Operation
MME/SGSN
GMLC
PROVIDE SUBSCRIBER LOCATION REQUEST
PROVIDE SUBSCRIBER LOCATION RESPONSE

Figure 6.2.2-1: Provide Subscriber Location procedure. Successful operation.
The GMLC initiates the procedure by sending a PROVIDE SUBSCRIBER LOCATION REQUEST message to the
MME or SGSN. This message carries the type of location information requested (e.g. current location and optionally,
velocity), the UE subscriber's IMSI, LCS QoS information (e.g. accuracy, response time), an indication of whether the
LCS client has the override capability, and an indication of whether delayed location reporting for UEs transiently not
reachable (e.g. UEs in extended idle mode DRX or Power Saving Mode) is supported as specified in clauses 9.1.6 and
9.1.15 of 3GPP TS 23.271 [2]. The message also carries an LCS reference number, if delayed location reporting is
supported. For deferred MT-LR procedure, additionally, the message carries Deferred location type, LCS reference
number, H-GMLC address, periodic LDR info etc.
Upon reception of PROVIDE SUBSCRIBER LOCATION REQUEST message, the MME or SGSN shall perform
authentication privacy verification on the location request. After that, for EPC-MT-LR or PS-MT-LR procedures the
MME or SGSN shall retrieve the location information of the target UE from E-UTRAN or UTRAN/GERAN according
to the procedures described in 3GPP TS 23.271 [2].
The MME or SGSN returns a PROVIDE SUBSCRIBER LOCATION RESPONSE to the GMLC. For EPC-MT-LR or
PS-MT-LR procedures, if the target UE is transiently not reachable and delayed location reporting for UEs transiently
not reachable is supported, the message shall contain an indication that the UE is transiently not reachable; otherwise
the message shall contain the location estimate, its age and obtained accuracy. If the MME or SGSN failed to get the
current location and the LCS client is requesting the current or last known location, the MME or SGSN may return the
last known location of the target UE if this is known.
If the GMLC has received indication from the HSS indicating the combined MME/SGSN node supporting the
optimized LCS procedure (see 3GPP TS 29.173 [18] clause 5.2.1.2) and if the GMLC also supports optimized LCS
procedure, the GMLC shall set the "Optimized-LCS-Proc-Req" bit within the PLR-Flags of the PROVIDE
SUBSCRIBER LOCATION REQUEST message during EPC-MT-LR and/or PS-MT-LR procedures. When the
combined MME/SGSN receives this message with "Optimized-LCS-Proc-Req" bit within the PLR-Flags set, the
combined MME/SGSN shall perform EPC-MT-LR or PS-MT-LR procedure depending upon the knowledge of the
current RAT type of the UE. E.g. if the UE is in active mode in E-UTRAN, the combined MME/SGSN shall perform
only EPC-MT-LR procedure; if the ISR activated UE is in idle mode, the combined MME/SGSN shall perform the
paging followed by either EPC-MT-LR or PS-MT-LR procedure (depending upon the RAT where the UE is active).
Hence, the combined MME/SGSN shall perform optimized LCS procedure to retrieve the location information of the
target UE from either E-UTRAN or UTRAN/GERAN.
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The combined MME/SGSN shall return a PROVIDE SUBSCRIBER LOCATION RESPONSE to the GMLC. If the
target UE is transiently not reachable and delayed location reporting for UEs transiently not reachable is supported, the
message shall contain an indication that the UE is transiently not reachable; otherwise the message shall contain the
location estimate, its age and obtained accuracy. If the combined MME/SGSN failed to get the current location and the
LCS client is requesting the current or last known location, the combined MME/SGSN should return the latest of the
last known EPS or UTRAN/GERAN location of the target UE if this is known. In both the cases, the combined
MME/SGSN may set "Optimized-LCS-Proc-Performed" bit within PLA-Flags, if it has performed optimized LCS
procedure.
This procedure is mapped to the commands Provide-Location-Request/Answer in the Diameter application specified in
clauses 7.3.1 and 7.3.2.
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Table 6.2.2-1: Provide Subscriber Location Request
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Information Mapping to Cat. Description
element name Diameter AVP
Location Type SLg-Location- M This Information Element shall contain the type of location
Type measurement requested, such as current location, initial location, last
known location, etc. (see 3GPP TS 22.071 [15]).
IMSI User-Name C If present, this Information Element shall contain the IMSI of the user
whose UE is to be positioned (see Note 1).
MSISDN MSISDN C If present, this Information Element shall contain the MSISDN of the
user whose UE is to be positioned (see Note 1).
IMEI IMEI C If present, this Information Element shall contain the IMEI of the UE
to be positioned (see Note 1).
Client Name LCS-EPS-Client- M This Information Element shall contain the name of the LCS client
Name issuing the positioning request.
Client Type LCS-Client-Type M This Information Element shall contain the type of LCS client
(Emergency, Lawful Interception …) issuing the positioning request
(see 3GPP TS 23.271 [2] and 3GPP TS 32.299 [10]).
Requestor Name LCS-Requestor- O If present, this Information Element contains the identity of the
Name originating entity which has requested the location of the target UE
from the LCS Client.
Priority LCS-Priority O If present, this Information Element shall contain the priority of the
LCS client issuing the positioning request.
QoS LCS-QoS O If present, this Information Element shall contain the quality of service
requested, such as the accuracy of the positioning measurement and
the response time of the positioning operation.
Velocity Requested Velocity- O If present, this information element shall contain an indication of
Requested whether or not the Velocity of the target UE is requested.
Supported GAD LCS-Supported- O If present, this Information Element shall contain the list of supported
Shapes GAD-Shapes GAD shapes by the LCS client.
Service Type ID LCS-Service- O If present, this Information Element shall contain the service type
Type-ID associated for the particular positioning request (the meaning of the
different service types is defined in 3GPP TS 22.071 [15]).
Codeword LCS-Codeword O If present, this Information Element shall contain the Codeword to be
used between an LCS client and a target UE in order to check and
accept or reject the positioning request.
APN Service-Selection C If present, this Information Element shall contain the Access Point
Name (APN) Network Identifier of the LCS client, as used by the
target UE. It shall only be included in session-related location
requests.
Session-Related LCS-Privacy- O If present, this Information Element shall contain an indication of how
Privacy Check Check-Session the positioning operation should proceed in the relation to the
checking of the session-related privacy settings of the user.
Non-Session- LCS-Privacy- O If present, this Information Element shall contain an indication of how
Related Privacy Check-Non- the positioning operation should proceed in the relation to the
Check Session checking of the non-session-related privacy settings of the user.
Deferred Location Deferred- O If present, this Information Element shall contain the type of the event
Type Location-Type until when the location estimation is deferred. Various applicable
eve
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