ETSI TS 129 173 V16.0.0 (2020-07)

Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; Location Services (LCS); Diameter-based SLh interface for Control Plane LCS (3GPP TS 29.173 version 16.0.0 Release 16)

RTS/TSGC-0429173vg00

General Information

• Status: Not Published
• Technical Committee: 3GPP CT 4 - MAP/CAMEL/GTP/BCH/SS/TrFO/IMS/GUP/WLAN (formely CN4)
• Current Stage: 12 - Completion
• Completion Date: 23-Jul-2020

Standards Content (Sample)

ETSI TS 129 173 V16.0.0 (2020-07)






TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
Location Services (LCS);
Diameter-based SLh interface for Control Plane LCS
(3GPP TS 29.173 version 16.0.0 Release 16)

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3GPP TS 29.173 version 16.0.0 Release 16 1 ETSI TS 129 173 V16.0.0 (2020-07)



Reference
RTS/TSGC-0429173vg00
Keywords
GSM,LTE,UMTS
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3GPP TS 29.173 version 16.0.0 Release 16 2 ETSI TS 129 173 V16.0.0 (2020-07)
Intellectual Property Rights
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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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Modal verbs terminology
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"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
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3GPP TS 29.173 version 16.0.0 Release 16 3 ETSI TS 129 173 V16.0.0 (2020-07)
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 Abbreviations . 7
4 General Description . 7
4.1 Introduction . 7
4.2 Architecture Overview . 7
4.3 Functional Requirements of SLh Interface . 8
5 Diameter-based SLh Interface . 8
5.1 Introduction . 8
5.2 Procedure Descriptions . 8
5.2.1 Send Routing Information for LCS . 8
5.2.1.1 General . 8
5.2.1.2 Detailed Behaviour of the HSS . 10
5.2.1.3 Detailed Behaviour of the GLMC . 11
6 Protocol Specification and Implementations . 11
6.1 Introduction . 11
6.1.1 Use of Diameter Base Protocol . 11
6.1.2 Securing Diameter Messages . 11
6.1.3 Accounting Functionality . 12
6.1.4 Use of Sessions . 12
6.1.5 Transport Protocol . 12
6.1.6 Routing Considerations . 12
6.1.7 Advertising Application Support . 12
6.1.8 Diameter Application Identifier . 12
6.1.9 User Identity to HSS resolution . 13
6.2 Commands . 13
6.2.1 Introduction. 13
6.2.2 Command-Code values . 13
6.2.3 LCS-Routing-Info-Request (RIR) Command . 13
6.2.4 LCS-Routing-Info-Answer (RIA) Command . 14
6.3 Result-Code AVP and Experimental-Result AVP Values . 15
6.3.1 General . 15
6.3.2 Success . 15
6.3.3 Permanent Failures . 15
6.3.3.1 DIAMETER_ERROR_USER_UNKNOWN (5001) . 15
6.3.3.2 DIAMETER_ERROR_UNAUTHORIZED_REQUESTING_NETWORK (5490) . 15
6.3.4 Transient Failures . 15
6.3.4.1 DIAMETER_ERROR_ABSENT_USER (4201) . 15
6.4 AVPs . 15
6.4.1 General . 15
6.4.2 LMSI . 16
6.4.3 Serving-Node . 16
6.4.4 MME-Name . 17
6.4.5 MSC-Number . 17
6.4.6 LCS-Capabilities-Sets . 17
6.4.7 GMLC-Address . 17
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6.4.8 Additional-Serving-Node . 17
6.4.9 PPR-Address . 18
6.4.10 Feature-List-ID AVP . 18
6.4.11 Feature-List AVP . 18
6.4.12 MME-Realm . 18
6.4.13 SGSN-Name . 18
6.4.14 SGSN-Realm . 18
Annex A (informative): Change history . 20
History . 21

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3GPP TS 29.173 version 16.0.0 Release 16 5 ETSI TS 129 173 V16.0.0 (2020-07)
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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3GPP TS 29.173 version 16.0.0 Release 16 6 ETSI TS 129 173 V16.0.0 (2020-07)
1 Scope
The present document describes the Diameter-based SLh interface between the GMLC and the HSS defined for the
Control Plane LCS in EPC.
LCS procedures over the SLh interface are defined in the 3GPP TS 23.271 [2].
This specification defines the Diameter application for the GMLC-HSS, SLh reference point. The interactions between
the HSS and the GMLC are specified, including the signalling flows. As LCS procedures over the Diameter-based SLh
interface are identical to the MAP-based Lh interface, the descriptions of the Lh MAP operations defined in the 3GPP
TS 29.002 [3] are mapped into the descriptions of the SLh Diameter commands.
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 29.002: "Mobile Application Part (MAP) specification".
[4] 3GPP TS 29.228: "IP multimedia (IM) Subsystem Cx Interface; Signalling flows and Message
Elements".
[5] Void.
[6] 3GPP TS 33.210: "3G security; Network Domain Security (NDS); IP network layer security".
[7] IETF RFC 4960: "Stream Control Transport Protocol".
[8] 3GPP TS 29.229: "Cx and Dx Interfaces based on the Diameter protocol; protocol details".
[9] 3GPP TS 29.329: "Sh Interface based on the Diameter protocol; protocol details".
[10] 3GPP TS 23.003: "Numbering, addressing and identification ".
[11] 3GPP TS 23.012: "Location Management Procedures".
[12] 3GPP TS 29.272: "Mobility Management Entity (MME) and Serving GPRS Support Node
(SGSN) related interfaces based on Diameter protocol".
[13] IETF RFC 2234: "Augmented BNF for syntax specifications".
[14] Void
[15] ITU-T Recommendation E.164: "The international public telecommunication numbering plan".
[16] 3GPP TS 29.273: "Evolved Packet System (EPS); 3GPP EPS AAA interfaces".
[17] IETF RFC 6733: "Diameter Base Protocol".
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3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1], 3GPP TS 23.271 [2]
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].
3.2 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].
ABNF Augmented Backus-Naur form
AVP Attribute Value Pair
H-GMLC Home-Gateway Mobile Location Centre
IANA Internet Assigned Numbers Authority
PMD Pseudonym mediation device functionality
PPR Privacy Profile Register
R-GMLC Requesting-Gateway Mobile Location Centre
RFC Request For Comments
V-GMLC Visited-Gateway Mobile Location Centre
4 General Description
4.1 Introduction
The SLh reference point between the GMLC and the HSS is defined in the 3GPP TS 23.271 [2].
This document describes the Diameter-based SLh interface related procedures, message parameters and protocol
specifications.
4.2 Architecture Overview
The architecture for support of Location Services in GSM, UMTS and EPS has been defined in 3GPP TS 23.271 [2]
and the relevant network elements and interfaces are shown in the figure 4.2-1.
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HSS
SLh
GMLC
Le SLg Lg Lpp Lid La
Lg
External MSC/
AAA
MME SGSN PPR PMD
LCS Client MSC Server
Server

Figure 4.2-1: Overview of the LCS Functional Architecture
In this architecture, the SLh interface is defined between the Gateway Mobile Location Center (GMLC) and the Home
Subscriber Server (HSS) to allow the GMLC to request routing information from the HLR or HSS.
4.3 Functional Requirements of SLh Interface
The requirements for SLh interface are defined in 3GPP TS 23.271 [2].
The SLh interface is used by the GMLC to request routing information from the HSS i.e. the address of the H-GMLC,
and/or the address of the visited MSC/MSC server, SGSN, 3GPP AAA server or MME for a particular target UE whose
location has been requested.
5 Diameter-based SLh Interface
5.1 Introduction
This section describes the Diameter-based SLh interface related procedures and Information elements exchanged
between functional entities.
In the tables that describe the Information Elements transported by each Diameter command, each Information Element
is marked as (M) Mandatory, (C) Conditional or (O) Optional in the "Cat." column. For the correct handling of the
Information Element according to the category type, see the description detailed in section 6 of the 3GPP TS 29.228 [4].
5.2 Procedure Descriptions
5.2.1 Send Routing Information for LCS
5.2.1.1 General
This procedure is used between the GMLC and the HSS. The procedure is invoked by the GMLC and is used:
- To retrieve routing information for LCS for a specified user from the HSS.
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This procedure is mapped to the commands LCS-Routing-Info-Request/Answer in the Diameter application specified in
chapter 6. Tables 5.2.1.1/1 and 5.2.1.1/2 detail the involved information elements.
Table 5.2.1.1/1: Send Routing Information for LCS (SLh-LCS-SRI)
Information Mapping to Cat. Description
element name Diameter AVP
IMSI User-Name C This information element shall contain the IMSI of the targeted
user. This IE shall be present if the MSISDN is absent.
MSISDN MSISDN C This information element shall contain the MSISDN of the
targeted user. This IE shall be present if the IMSI is absent.
GMLC Number GMLC-Number O This information element shall contain the ISDN (E.164)
number of the requesting GMLC.
Supported Features Supported-Features O If present, this information element shall contain the list of
(See 3GPP TS features supported by the origin host.
29.229 [8])

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Table 5.2.1.1/2: Send Routing Information for LCS (SLh-LCS-SRI) Resp
Information Mapping to Cat. Description
element Diameter AVP
name
Result Result-Code / M Result of the request.
(See 5.3.5) Experimental- Result-Code AVP shall be used for errors defined in the Diameter base
Result protocol (see IETF RFC 6733 [17]).
Experimental-Result AVP shall be used for SLh errors. This is a
grouped AVP which contains the 3GPP Vendor ID in the Vendor-Id
AVP, and the error code in the Experimental-Result-Code AVP.
IMSI User-Name C This information element shall contain the IMSI of the targeted user.
This IE shall be present if Result-Code is DIAMETER_SUCCESS and
the MSISDN is absent.
MSISDN MSISDN C This information element shall contain the MSISDN of the targeted user.
This IE shall be present if Result-Code is DIAMETER_SUCCESS and
the IMSI is absent.
LMSI LMSI C This information element shall contain the LMSI allocated by the VLR.
This IE should be present if Result-Code is DIAMETER_SUCCESS and
LMSI is available in the HSS and MSC-Number is included in the
Serving-Node AVP or in an Additional-Serving-Node AVP.
Serving Node Serving-Node C This information element shall contain the information about the network
node serving the targeted user i.e. the name/number of the serving
node (MME, SGSN, 3GPP AAA server or MSC/MSC server), the LCS
capabilities sets supported by the serving node and the IP address of
the visited GMLC associated with the serving node. This IE shall be
present if the Result- Code is DIAMETER_SUCCESS; otherwise it shall
be absent.
Additional Additional- C This information element shall contain the information about another
Serving Node Serving-Node network node serving the targeted user. This IE may be present if
Result- Code is DIAMETER_SUCCESS; otherwise it shall be absent.
There may be multiple instances of this IE in the response provided by
the HSS.
Home GMLC GMLC-Address C This information element shall contain the IP address of the H-GMLC.
Address This IE should be present if the Result-Code is DIAMETER_SUCCESS;
otherwise it shall be absent.
PPR Address PPR-Address C This information element shall contain the IP address of the Privacy
Profile Register (PPR). This IE should be present if available in the HSS
and the Result-Code is DIAMETER_SUCCESS; otherwise it shall be
absent.
RIA Flags RIA-Flags O This Information Element contains a bit mask. See 6.4.15 for the
meaning of the bits.
Supported Supported- O If present, this information element shall contain the list of features
Features Features supported by the origin host.
(See 3GPP TS
29.229 [8])

5.2.1.2 Detailed Behaviour of the HSS
Upon reception of the Send Routing Info for LCS request, the HSS shall, in the following order:
1. Check whether the requesting GMLC belongs to a network authorized to request UE location information. If not,
Experimental-Result shall be set to DIAMETER_ERROR_UNAUTHORIZED_REQUESTING_NETWORK in
the Send Routing Information for LCS Response.
2. Check that the User Identity for whom data is asked exists in HSS. If not, Experimental-Result shall be set to
DIAMETER_ERROR_USER_UNKNOWN in the Send Routing Information for LCS Response.
2a. If both IMSI and MSISDN are present in the request, check whether they identify the same User. If not, the HSS
Result-Code shall be set to DIAMETER_CONTRADICTING_AVPS in the Send Routing Information for LCS
Response.
3. Check that there is at least one serving node associated with the targeted user. If not, Experimental-Result shall
be set to DIAMETER_ERROR_ABSENT_USER in the Send Routing Information for LCS Response.
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If there is an error in any of the above steps then the HSS shall stop processing and shall return the error code specified
in the respective step (see 3GPP TS 29.329 [9] and 3GPP TS 29.229 [8] for an explanation of the error codes).
If the HSS cannot fulfil the received request for reasons not stated in the above steps, e.g. due to a database error or
empty mandatory data elements, it shall stop processing the request and set Result-Code to
DIAMETER_UNABLE_TO_COMPLY.
Otherwise, the requested operation shall take place and the HSS shall return the Result-Code AVP set to
DIAMETER_SUCCESS. The HSS returns one or several of the network addresses of the current MME, SGSN,
3GPP AAA server and/or VMSC/MSC server, the LCS capabilities of the serving nodes if available, the V-GMLC
address associated with the serving nodes, if available, and whichever of the IMSI and MSISDN that was not provided
in the Send Routing Info for LCS request. If MSISDN was not provided in the Send Routing Info for LCS request and
the subscription is MSISDN-less, the HSS shall return the dummy MSISDN value (see 3GPP TS 23.003 [10]). If both
MSISDN and IMSI were provided in the Send Routing Info for LCS request, the HSS returns either MSISDN or IMSI
or both. The HSS returns the address of the H-GMLC. The HSS also provides the address of the PPR, if available.
The HSS shall include the Diameter Identity of the SGSN (i.e. SGSN-Name and SGSN-Realm), within the Serving-
Node AVP or within an Additional-Serving-Node AVP, if and only if the HSS has received an indication that the Lgd
interface is supported by the SGSN (see 3GPP TS 29.272 [12]).
The HSS shall include the SGSN Number, within the Serving-Node AVP or Additional Serving-Node AVP, except if
the HSS has received an indication that the Lg interface is not supported by the SGSN (see 3GPP TS 29.272 [12]).
If the UE is served by the MME and SGSN parts of the same combined MME/SGSN (see 3GPP TS 29.272 [12]
subclause 5.2.2.1.1 for how the HSS determines if the UE is served by the combined MME/SGSN) and if this combined
MME/SGSN has indicated the support for optimized LCS procedure (via the Supported-Feature AVP as defined in
3GPP TS 29.272 [12] subclause 7.3.10) and if HSS supports this optimized LCS procedure, then the HSS shall set the
"Combined-MME/SGSN-Supporting-Optimized-LCS-Proc" bit of the RIA-Flags.
Regarding the LCS capabilities of the serving nodes, if the HSS registered an SGSN via the S6d reference point (i.e.,
the registered serving node is an S4-SGSN), the HSS shall set the LCS-Capabilities-Set value to indicate support of
Capability Set 5 (i.e., LCS release 7 or later version). If the HSS registered an MME, the HSS shall not indicate any
LCS capability value to the GMLC (i.e., the LCS-Capabilities-Set AVP shall be absent over SLh when the serving node
is an MME); in this case, the GMLC shall assume that the MME supports LCS Capability Set 5.
5.2.1.3 Detailed Behaviour of the GLMC
If there are a serving node as well as additional serving nodes in a successful Send Routing Info for LCS response, the
receiving shall use the serving node in preference to the additional serving nodes.
6 Protocol Specification and Implementations
6.1 Introduction
6.1.1 Use of Diameter Base Prot
...