TS 29.171 – LCS-AP between MME and E-SMLC (SLs)
3GPP TS 29.171 is the 3GPP Technical Specification for LCS-AP between MME and E-SMLC (SLs). Its official 3GPP title is “Location Services (LCS); LCS Application Protocol (LCS-AP) between the Mobile Management Entity (MME) and Evolved Serving Mobile Location Centre (E-SMLC); SLs interface”. It is published in 11 releases (Rel-9 to Rel-19); the latest version is 19.1.0 in Rel-19.
Specifies LCS Application Protocol procedures and message encoding for location services over the SLs interface between MME and E-SMLC.
Releases and versions of TS 29.171
| Release | Latest version | Links |
|---|---|---|
| Rel-19 | 19.1.0 | Read · Download (3GPP) |
| Rel-18 | 18.1.0 | Read · Download (3GPP) |
| Rel-17 | 17.4.0 | Read · Download (3GPP) |
| Rel-16 | 16.6.0 | Read · Download (3GPP) |
| Rel-15 | 15.5.1 | Read · Download (3GPP) |
| Rel-14 | 14.3.0 | Read · Download (3GPP) |
| Rel-13 | 13.3.0 | Read · Download (3GPP) |
| Rel-12 | 12.3.0 | Read · Download (3GPP) |
| Rel-11 | 11.4.0 | Read · Download (3GPP) |
| Rel-10 | 10.5.0 | Read · Download (3GPP) |
| Rel-9 | 9.4.0 | Read · Download (3GPP) |
Scope of TS 29.171
Category: Core Network (Location Services (LCS)). Technology generation: 4G. Network layer: CoreNetwork.
Who should read this specification?
- Network operators
- Device manufacturers
- Regulators and standards bodies
Protocols and interfaces
Protocols: SCTP, LPP, LPPa
Interfaces: SLs, S1-MME, Uu
Key use cases
- Location Services
- Emergency Services
- Assisted GNSS
Implementation notes
Complexity level: Advanced. Implementation difficulty: High.
Key technologies
Specifications referenced by TS 29.171
- TS 22.071 Location Services (LCS) Stage 1
- TS 23.003 Numbering, Addressing and Identification
- TS 24.301 EPS NAS Mobility and Session Management
- TR 21.905 3GPP Terminology and Definitions
- TS 36.305 UE Positioning in E-UTRAN Stage 2
- TS 23.271 LCS Stage 2 Specification
- TS 23.032 Universal Geographical Area Description
- TS 36.413 S1 Application Protocol (S1AP) for E-UTRAN
Specifications that reference TS 29.171
Other specifications in the 29 series
- TS 29.163 Interworking between 3GPP IM CN and CS networks
- TS 29.164 CS-LTE Interworking with SIP-I, BICC, ISUP
- TS 29.165 Inter-IMS Network-to-Network Interface (II-NNI)
- TS 29.168 SBc-AP Protocol Specification
- TS 29.172 EPC LCS Protocol (ELP) specification
- TS 29.173 Diameter-based SLh Interface for LCS
- TS 29.175 Nimsas Service Based Interface for IMS AS
- TS 29.176 Nmf Media Resource Management Service
Related glossary terms
Related topics
Related technologies
Frequently asked questions
What is 3GPP TS 29.171?
3GPP TS 29.171 is the 3GPP Technical Specification for LCS-AP between MME and E-SMLC (SLs). Specifies LCS Application Protocol procedures and message encoding for location services over the SLs interface between MME and E-SMLC.
Which 3GPP releases include TS 29.171?
TS 29.171 is published in 11 releases, from Rel-9 to Rel-19. The latest version on 3GPP Explorer is 19.1.0 (Rel-19).
What category does TS 29.171 belong to?
TS 29.171 belongs to the Core Network (Location Services (LCS)) category of 3GPP specifications. It applies to 4G networks.
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