ETSI TS 124 571 V18.8.0 (2026-03)

5G; 5G System (5GS); Control plane Location Services (LCS) procedures; Stage 3 (3GPP TS 24.571 version 18.8.0 Release 18)

RTS/TSGC-0124571vi80

General Information

• Status: Not Published
• Technical Committee: 3GPP CT 1 - MM/CC/SM [lu] (formely CN1)
• Current Stage: 8 - Draft receipt by ETSI Secretariat
• Completion Date: 10-Mar-2026

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
5G System (5GS);
Control plane Location Services (LCS) procedures;
Stage 3
(3GPP TS 24.571 version 18.8.0 Release 18)

3GPP TS 24.571 version 18.8.0 Release 18 1 ETSI TS 124 571 V18.8.0 (2026-03)

Reference
RTS/TSGC-0124571vi80
Keywords
5G
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ETSI
3GPP TS 24.571 version 18.8.0 Release 18 2 ETSI TS 124 571 V18.8.0 (2026-03)
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Modal verbs terminology
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ETSI
3GPP TS 24.571 version 18.8.0 Release 18 3 ETSI TS 124 571 V18.8.0 (2026-03)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 5
1 Scope . 7
2 References . 7
3 Definitions of terms, symbols and abbreviations . 7
3.1 Terms . 7
3.2 Symbols . 8
3.3 Abbreviations . 8
4 General . 8
4.1 Overview . 8
4.1.1 NAS aspect . 8
4.1.2 LCS aspect . 8
4.2 LCS Support capabilities . 9
4.2.1 UE support of LCS . 9
4.2.2 Network support of LCS . 10
5 Support of LCS signalling . 10
5.1 General . 10
5.2 LCS operations . 10
5.2.1 Network initiated location services operations . 10
5.2.1.1 Supplementary Services Location Notification . 10
5.2.1.1.1 General . 10
5.2.1.1.2 Normal operation . 11
5.2.1.2 Positioning Information Transport . 12
5.2.1.3 Supplementary Services Periodic or Triggered Location . 13
5.2.1.3.1 General . 13
5.2.1.3.2 Normal operation . 15
5.2.1.4 Supplementary Services Cancel Deferred Location . 16
5.2.1.4.1 General . 16
5.2.1.4.2 Normal operation . 17
5.2.1.5 Network initiated PRU disassociation procedure . 18
5.2.1.5.1 General . 18
5.2.1.5.2 Normal operation . 19
5.2.1.6 Sidelink Positioning Information Transport . 20
5.2.1.7 Network initiated RSPP supplementary information transport . 21
5.2.1.7.1 General . 21
5.2.1.7.2 Normal operation . 21
5.2.1.8 Sidelink mobile terminating location request . 22
5.2.1.8.1 General . 22
5.2.1.8.2 Normal operation . 22
5.2.2 Mobile initiated location services operations . 24
5.2.2.1 Mobile Originated Location Request(MO-LR) . 24
5.2.2.1.1 General . 24
5.2.2.1.2 Normal operation . 25
5.2.2.2 UE initiated Cancel Deferred Location . 29
5.2.2.2.1 General . 29
5.2.2.2.2 Normal operation . 30
5.2.2.3 UE initiated Positioning Information Transport . 31
5.2.2.4 UE initiated Event Reporting Procedure . 32
5.2.2.4.1 General . 32
5.2.2.4.2 Normal operation . 33
5.2.2.5 UE Location Privacy Setting Procedure . 34
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5.2.2.5.1 General . 34
5.2.2.5.2 Normal operation . 35
5.2.2.6 UE initiated Event Reporting Procedure for Low Power Event Reporting and Triggered 5GC-
MT-LR . 36
5.2.2.6.1 General . 36
5.2.2.6.2 Normal operation . 37
5.2.2.7 PRU association procedure . 37
5.2.2.7.1 General . 37
5.2.2.7.2 Normal operation . 38
5.2.2.8 UE initiated PRU disassociation procedure . 40
5.2.2.8.1 General . 40
5.2.2.8.2 Normal operation . 41
5.2.2.9 Sidelink Mobile Originated Location Request (SL-MO-LR) . 42
5.2.2.9.1 General . 42
5.2.2.9.2 Normal operation . 43
5.2.2.10 UE initiated Sidelink Positioning Information Transport. 47
5.2.2.11 UE initiated RSPP supplementary information transport . 48
5.2.2.11.1 General . 48
5.2.2.11.2 Normal operation . 48
5.3 LCS message and coding . 49
5.3.1 Messages for Location services operations . 49
5.3.2 Messages for LTE Positioning Protocol (LPP) . 49
5.3.2.1 Downlink Positioning Information Transport using LPP messages . 49
5.3.2.2 Uplink Positioning Information Transport using LPP messages . 50
5.3.3 Messages for SideLink Positioning Protocol (SLPP) . 50
5.3.3.1 Downlink Positioning Information Transport using SLPP messages . 50
5.3.3.2 Uplink Positioning Information Transport using SLPP messages . 50
Annex A (informative): Change history . 51
History . 54

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Foreword
This Technical Specification has been produced by the 3rd 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.
In the present document, modal verbs have the following meanings:
shall indicates a mandatory requirement to do something
shall not indicates an interdiction (prohibition) to do something
The constructions "shall" and "shall not" are confined to the context of normative provisions, and do not appear in
Technical Reports.
The constructions "must" and "must not" are not used as substitutes for "shall" and "shall not". Their use is avoided
insofar as possible, and they are not used in a normative context except in a direct citation from an external, referenced,
non-3GPP document, or so as to maintain continuity of style when extending or modifying the provisions of such a
referenced document.
should indicates a recommendation to do something
should not indicates a recommendation not to do something
may indicates permission to do something
need not indicates permission not to do something
The construction "may not" is ambiguous and is not used in normative elements. The unambiguous constructions
"might not" or "shall not" are used instead, depending upon the meaning intended.
can indicates that something is possible
cannot indicates that something is impossible
The constructions "can" and "cannot" are not substitutes for "may" and "need not".
will indicates that something is certain or expected to happen as a result of action taken by an agency
the behaviour of which is outside the scope of the present document
will not indicates that something is certain or expected not to happen as a result of action taken by an
agency the behaviour of which is outside the scope of the present document
might indicates a likelihood that something will happen as a result of action taken by some agency the
behaviour of which is outside the scope of the present document
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might not indicates a likelihood that something will not happen as a result of action taken by some agency
the behaviour of which is outside the scope of the present document
In addition:
is (or any other verb in the indicative mood) indicates a statement of fact
is not (or any other negative verb in the indicative mood) indicates a statement of fact
The constructions "is" and "is not" do not indicate requirements.
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1 Scope
The present document specifies the operations and information coding for the Non-Access Stratum (NAS) layer
protocol for supporting the Location Services (LCS) in the NG-RAN.
The present document is applicable to the User Equipment (UE) and to the Access and Mobility Management Function
(AMF) or Location Management Function (LMF) in the 5G System (5GS).
The present document is developed in accordance to the general principles stated in 3GPP TS 23.273 [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 23.273: "5G System (5GS) Location Services (LCS); Stage 2".
[3] 3GPP TS 24.501: "Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3".
[4] 3GPP TS 37.355: "LTE Positioning Protocol (LPP)".
[4a] 3GPP TS 38.355: "Sidelink Positioning Protocol (SLPP); Protocol specification".
[5] 3GPP TS 24.080: "Mobile radio interface layer 3 supplementary services specification; Formats
and coding".
[6] 3GPP TS 29.572: "5G System; Location Management Services; Stage 3".
[7] 3GPP TS 38.305: "Stage 2 functional specification of User Equipment (UE) positioning in NG-
RAN".
[8] 3GPP TS 22.261: "Service requirements for the 5G system; Stage 1".
[9] 3GPP TS 24.572: "User Plane Location Services (LCS) Protocols And Procedures; Stage 3".
[10] 3GPP TS 23.586: "Architectural Enhancements to support; Ranging based services and Sidelink
Positioning".
[11] 3GPP TS 38.455: "NG-RAN; NR Positioning Protocol A (NRPPa)".
3 Definitions of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the terms given in 3GPP 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 3GPP TR 21.905 [1].
For the purposes of the present document, the following terms and definitions given in 3GPP TS 22.261 [8] apply:
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satellite NG-RAN
PRU ON/OFF state: This state is defined for a UE associated as a PRU with an LMF (i.e. after the successful
completion of PRU association procedure). This state indicates whether the PRU functionality of the UE is activated
(i.e. ON state) or deactivated (i.e. OFF state) while it is associated with an LMF.
UE operating as PRU: From the UE perspective, a UE which supports PRU functionality and operates as PRU. From
the network perspective, the UE allowed to operate as a PRU based on the UE subscription data and the PRU state is
ON.
3.2 Symbols
3.3 Abbreviations
For the purposes of the present document, the abbreviations given in 3GPP 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
3GPP TR 21.905 [1].
5GCN 5G Core Network
5GS 5G System
AMF Access and Mobility Management Function
DL Downlink
IE Information Element
GMLC Gateway Mobile Location Centre
LCS Location Services
LDR Location Deferred Request
LMF Location Management Function
LPP LTE Positioning Protocol
MO-LR Mobile Originated Location Request
MT-LR Mobile Terminated Location Request
NAS Non-access Stratum
PRU Positioning Reference Unit
RSPP Ranging and sidelink positioning protocol
SLPP SideLink Positioning Protocol
SNPN Stand-alone Non-Public Network
UE User Equipment
UL Uplink
4 General
4.1 Overview
4.1.1 NAS aspect
To enable transfer of Location Services (LCS) signaling messages between the 5G core network (5GCN) and the UE,
two Payload container types are defined in the downlink (DL NAS TRANSPORT message) and the uplink (UL NAS
TRANSPORT message or CONTROL PLANE SERVICE REQUEST message). The message protocol and procedures
are described in 3GPP TS 24.501 [3].
4.1.2 LCS aspect
LCS uses the defined payload container to transfer LCS signalling messages between the UE and the network.
The corresponding LCS signaling messages include:
a) LTE Positioning Protocol (LPP) messages (see 3GPP TS 37.355 [4]):
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- Both downlink and uplink LPP messages are supported.
- Routing information is transported as the Additional information IE in UL/DL NAS TRANSPORT message
for LPP messages (see 3GPP TS 24.501 [3]).
a1) SideLink Positioning Protocol (SLPP) messages (see 3GPP TS 38.355 [4a]):
- Both downlink and uplink SLPP messages are supported.
- Routing information is transported as the Additional information IE in UL/DL NAS TRANSPORT message
for SLPP messages (see 3GPP TS 24.501 [3]).
b) Location services messages:
- Messages for MO-LR operations (see 3GPP TS 24.080 [5]).
- Messages for LocationNotification operations (see 3GPP TS 24.080 [5]).
- Messages for EventReport operations (see 3GPP TS 24.080 [5]).
- Messages for PeriodicTriggeredInvoke operations (see 3GPP TS 24.080 [5]).
- Messages for CancelDeferredLocation operations (see 3GPP TS 24.080 [5]).
- Messages for MSCancelDeferredLocation operations (see 3GPP TS 24.080 [5]).
- Messages for LocationPrivacySetting operations (see 3GPP TS 24.080 [5]).
- Messages for PRU-Association operations (see 3GPP TS 24.080 [5]).
- Messages for SL-MO-LR operations (see 3GPP TS 24.080 [5]).
- Messages for SL-MT-LR operations (see 3GPP TS 24.080 [5]).
- Routing information associated with the LMF is transported as the Additional information IE in UL/DL NAS
TRANSPORT message or CONTROL PLANE SERVICE REQUEST message (see clause 5.2.2.6.1) for
Location services messages that are transported between the UE and the LMF (see 3GPP TS 24.501 [3]).
c) RSPP transport messages:
- Messages for ULRSPPTransport operations (see 3GPP TS 24.080 [5]).
- Messages for DLRSPPTransport operations (see 3GPP TS 24.080 [5]).
The Routing information transported as the Additional information IE can be Routing identifier in the current
specification, which includes immediate routing identifier and deferred routing identifier. The immediate routing
identifier transported as the Additional information IE is the Correlation ID, which is allocated by the AMF and can be
used in the UL/DL NAS TRANSPORT message (see clause 5.2 and clause 5.3). The deferred routing identifier
transported as the Additional information IE can be used in the UL NAS TRANSPORT and CONTROL PLANE
SERVICE REQUEST message for the AMF routing the LCS messages to the particular LMF (see clause 5.2.2).
The messages for PeriodicTriggeredInvoke operations can be used to enable the location events reporting over user
plane connection, and the messages for EventReport operations can be used for the cumulative event report, as
described in clause 6.16.1 of 3GPP TS 23.273 [2]. The location events reporting over user plane connection is defined
in 3GPP TS 24.572 [9]).
4.2 LCS Support capabilities
4.2.1 UE support of LCS
The UE announces to the network its ability to support LCS notification mechanism or LPP messages or both, using the
5GMM capability IE defined in 3GPP TS 24.501 [3].
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The UE supporting LCS notification mechanism and LPP messages may support PRU (defined in 3GPP TS 38.305 [7]).
The UE’s ability to support PRU is stored in the UDM (see 3GPP TS 23.273 [2]) without any indication in 5GMM
capability IE defined in 3GPP TS 24.501 [3].
A UE accessing 5G network via satellite NG-RAN shall not operate as a PRU.
4.2.2 Network support of LCS
The network announces to the UE its ability to support LCS in 5GC using the 5GS network feature support IE defined
in 3GPP TS 24.501 [3]. The information is taken into account by the UE, in addition to UE's LCS capabilities, for the
UE to determine whether to initiate MO-LR procedure in NG-RAN as specified in 3GPP TS 23.273 [3], clause 6.2.
NOTE: An SNPN can provide Location Services except for the cases of interworking with EPC, roaming, and
direct access to SNPN via non-3GPP access, which are not supported in an SNPN.
5 Support of LCS signalling
5.1 General
This clause defines the NG-RAN LCS operations (clause 5.2) and the format and coding of the messages (clause 5.3).
The messages defined in this clause can be transported in the UL/DL NAS Transport message defined in
3GPP TS 24.501 [3].
5.2 LCS operations
5.2.1 Network initiated location services operations
5.2.1.1 Supplementary Services Location Notification
5.2.1.1.1 General
The supplementary services Location Notification operation enables the AMF to trigger the end-user notification
verification process on the UE using NAS signalling. The supplementary services messages are transported using the
DL NAS Transport message and the UL NAS Transport message defined in 3GPP TS 24.501 [3]. UE Location Privacy
Indication information may be included in Location Notification Return Result to indicate whether subsequent LCS
requests or ranging and sidelink positioning requests will be allowed or disallowed by the UE. Figure 5.2.1.1.1.1
illustrates an example of the NAS signalling transport applicable to a 5GC-MT-LR procedure for immediate or deferred
location or to a SL-MT-LR procedure for immediate or deferred location.
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UE AMF
When a 5GC-MT-LR location Procedure or a SL-MT-LR location procedure is
initiated at the AMF, if the LCS notification/verification is required and is
supported by the UE, the AMF sets the Payload container type to “Location
services message container”, and includes LCS Notification Verification Invoke
in the Payload container in the DL NAS Transport message.
DL NAS Transport
(Payload container, (REGISTER (Facility (LCS-LocationNotification Invoke))))
After user notification and verification, the UE sets the Payload container type to
“Location services message container”, and includes an LCS Notification
Verification Return Result in the Payload container in the UL NAS Transport
message.
UL NAS Transport
(Payload container (RELEASE COMPLETE (Facility (LCS-LocationNotification Return Result))))

Figure 5.2.1.1.1.1: NAS signalling transport for Supplementary Services Location Notification
NOTE: The optional Additional information IE of the DL/UL NAS Transport message is not included when the
LCS Location Notification signalling is transported in the Payload container.
5.2.1.1.2 Normal operation
The network invokes a location notification procedure by sending a REGISTER message containing an LCS-
LocationNotification invoke component to the UE as defined in 3GPP TS 24.080 [5]. This may be sent either to request
verification for a 5GC-MT-LR or to notify the UE about an already authorized 5GC-MT-LR.
In case of privacy verification for LCS or ranging and sidelink positioning, the UE shall respond to the request by
sending a RELEASE COMPLETE message containing the user's response and optionally UE Location Privacy
Indication information in a return result component (see figure 5.2.1.1.2.1). If rangingSlExt is included, the privacy
verification is for ranging and sidelink positioning and the corresponding verification result for ranging and sidelink
positioning is included in UE Location Privacy Indication information.
During the supplementary services Location Notification operation, the network shall run the timer T(LCSN) defined in
3GPP TS 24.080 [5]. This timer is started when the operation is sent, and stopped when a response is received from the
UE. If the timer T(LCSN) expires in the network before any response from the UE (e.g. due to no response from the
user), the network shall interpret this by applying the default treatment defined in 3GPP TS 23.273 [2] (i.e. disallow
location if barred by subscription or allow location if allowed by subscription). The network may also terminate the
dialogue by sending a RELEASE COMPLETE message.
In the case of location notification, the UE shall terminate the dialogue immediately by sending a RELEASE
COMPLETE message containing a LocationNotification return result.
If the UE is unable to process the request received from the network, it shall return an error indication by sending a
RELEASE COMPLETE message containing a return error component. Error values are specified in
3GPP TS 24.080 [5].
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UE Network
REGISTER
<------------------------------------------------------------------------------------------------------------------------
Facility (Invoke = LCS-LocationNotification (notificationType, locationType, lcsClientExternalID, lcsClientName,
lcsCodeword, lcsServiceTypeId, deferredLocationExt, rangingSlExt))

RELEASE COMPLETE
------------------------------------------------------------------------------------------------------------------------>
Facility (Return result = LCS-LocationNotification (verificationResponse, locationPrivacyIndication, validTimePeriod))

RELEASE COMPLETE
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ->
Facility (Return error (Error))

RELEASE COMPLETE
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ->
Facility (Reject (Invoke_problem))

RELEASE COMPLETE
<- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Figure 5.2.1.1.2.1: Location Notification
5.2.1.2 Positioning Information Transport
The AMF sends an LPP message and an associated Correlation Identifier in the DL NAS Transport message (refer to
3GPP TS 24.501 [3] and 3GPP TS 23.273 [2] clause 6.11.1) to a UE, or a UE operating as PRU, or both.
Figure 5.2.1.2.1 illustrates an example of the NAS signalling transport for downlink LPP messages.
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UE AMF LMF
NAS signaling for 5GC-MO-LR, 5GC-MT-LR, or 5GC-NI-LR session initiation
may have occurred.
Case A: The AMF invokes an Nlmf_Location_DetermineLocation service
operation towards the LMF to request an immediate UE location, initiation of a
deferred location, transfer of assistance data to the UE or verify a UE geographical
area for satellite NG-RAN. The AMF also assigns and includes a Correlation
Identifier as described in 3GPP TS 23.273 clause 6.11.1 [2].
Case B: The AMF invokes an Namf_Communication_N1MessageNotify service
operation towards the LMF to transfer a supplementary services event report
message to the LMF for periodic or triggered location of the UE as described in
clause 6.3.1 of 3GPP TS 23.273 [2].
The LMF decides to exchange information with the UE using LPP messages and
invokes an Namf_Communication_N1N2MessageTransfer service operation
towards the AMF to request the transfer of an LPP message. For Case A, the LMF
includes the Correlation Identifier received from the AMF. For Case B, the LMF
assigns and includes a Correlation Identifier that identifies the LMF.
The AMF sets the Payload container type to “LPP message container” and
forwards the LPP message in the Payload container in the DL NAS Transport
message.
The AMF includes the Correlation Identifier received from the LMF in the
Additional Information IE of the DL NAS Transport message .
DL NAS Transport
(Payload container (LPP message), Additional Information
(Correlation Identifier))
Figure 5.2.1.2.1: NAS signalling transport for downlink LPP messages
NOTE 1: If a scheduled location time is received in the LPP message, the UE in 5GMM-IDLE mode can initiate a
service request procedure shortly before the scheduled location time.
NOTE 2: If the LMF determines that simultaneous measurements for UE and PRU(s) are needed, the LMF may
send the time window(s) rather than the scheduled location time in the LPP messages to the UE, PRU(s)
and NG-RAN. Definition of the time window and the associated configuration parameters are specified in
TS 37.355 [4] and TS 38.455 [11].
5.2.1.3 Supplementary Services Periodic or Triggered Location
5.2.1.3.1 General
The supplementary services LCS PeriodicTriggered Invoke operation enables the LMF to initiate periodic or triggered
location event reporting by a target UE as described in clause 6.3.1 of 3GPP TS 23.273 [2]. The supplementary services
LCS PeriodicTriggered Invoke message is transferred to the target UE via the serving AMF in a DL NAS Transport
message. A response from the target UE is similarly returned to the LMF via the serving AMF and is transferred to the
AMF in an UL NAS Transport message. If the LCS PeriodicTriggered Invoke message in the Payload container IE of a
DL NAS TRANSPORT message includes the deferred routing identifier, the UE shall include the deferred routing
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identifier in the Additional information IE of a UL NAS TRANSPORT message during the subsequent procedures as
specified in clause 5.2.2.
Figure 5.2.1.3.1.1 illustrates an example of the NAS signalling transport for initiation of periodic or triggered location.
UE AMF LMF
The AMF invokes an Nlmf_Location_DetermineLocation service operation towards the
LMF to request deferred location for periodic or triggered location. The AMF also assigns
and includes a Correlation Identifier as described in clause 6.3.1 of 3GPP TS 23.273 [2].
The LMF invokes an Namf_Communication_N1N2MessageTransfer service operation
towards the AMF to request the transfer of a supplementary services LCS
PeriodicTriggered Invoke message and includes the Correlation Identifier received from
the AMF.
The AMF sets the Payload container type to “Location services message
container” and includes the supplementary services LCS PeriodicTriggered
Invoke message in the Payload container in a DL NAS Transport message. The
AMF includes the Correlation Identifier in the Additional information IE.
DL NAS Transport
(Payload container (LCS PeriodicTriggered Invoke
message), Additional information (Correlation Identifier))
The UE determines whether the periodic or triggered location can
be supported and returns a supplementary services LCS
PeriodicTriggered Return Result message if the location can be
supported or a supplementary services LCS PeriodicTriggered
Return Error message if the location cannot be supported. The
supplementary services message is included in the Payload
container of an UL NAS Transport message, The Payload container
type is set to “Location services message container” and the
received Correlation Identifier is included in the Additional
information IE.
UL NAS Transport
(Payload container (LCS PeriodicTriggered Return Result),
Additional Information (Correlation Identifier))
The AMF invokes an Namf_Communication_N1MessageNotify service operation
towards the LMF to transfer the LCS PeriodicTriggered Return Result or the LCS
PeriodicTriggered Return Error. The AMF identifies the LMF using the Correlation
Identifier.
Figure 5.2.1.3.1.1: NAS signalling transport for LCS PeriodicTriggered messages
NOTE: If a scheduled location time is received in the LCS PeriodicTriggered Invoke message, the UE in 5GMM-
IDLE mode can initiate a service request procedure shortly before the scheduled location time.
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5.2.1.3.2 Normal operation
The LMF sends a REGISTER message to the UE containing the supplementary services LCS PeriodicTriggered Invoke
component as defined in 3GPP TS 24.080 [5]. The REGISTER message is transported to the UE via the serving AMF
as described in figure 5.2.1.3.1.1.
If the UE can support the periodic or triggered location, the UE returns a RELEASE COMPLETE message to the LMF
containing an LCS PeriodicTriggered return result. The RELEASE COMPLETE message is transported to the LMF via
the serving AMF as described in figure 5.2.1.3.1.1.
For supporting of the location events reporting over user plane connection, as described in clause 6.16.1 of
3GPP TS 23.273 [2], the LMF provides the UE with the following:
a) the endpoint address for the location reporting over user plane connection;
b) the security information for the location reporting over user plane connection;
c) the cumulative event report timer, if available; or
d) the maximum number of events reporting counter, if available.
If the UE receives the cumulative event report timer or the maximum number of events reporting counter from the
LMF, the UE shall perform the UE initiated Event Reporting procedure as defined in subclause 5.2.2.4 with including
the indication for the cumulative event report.
If the UE is unable to process or support the request received from the network, it shall return an error indication by
sending a RELEASE COMPLETE message containing a return error component or reject component. Error values are
specified in 3GPP TS 24.080 [5].
During the supplementary services periodic or triggered location operation, the network shall run a timer T. This timer
is started when the operation is sent, an
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