ETSI TS 149 031 V15.1.0 (2020-04)

TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Location Services (LCS);
Base Station System Application
Part LCS Extension (BSSAP-LE)
(3GPP TS 49.031 version 15.1.0 Release 15)

R
GLOBAL SYSTEM FOR
MOBILE COMMUNICATIONS
3GPP TS 49.031 version 15.1.0 Release 15 1 ETSI TS 149 031 V15.1.0 (2020-04)

Reference
RTS/TSGR-0649031vf10
Keywords
GSM
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ETSI
3GPP TS 49.031 version 15.1.0 Release 15 2 ETSI TS 149 031 V15.1.0 (2020-04)
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Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 7
1 Scope . 8
2 References . 8
3 Definitions, abbreviations and symbols . 9
4 Definition of BSSAP-LE . 9
4.1 DTAP-LE Messages . 9
4.2 BSSMAP-LE Messages . 10
5 Procedures applicable to use of BSSAP-LE . 10
5.1 Location Request . 10
5.1.1 Successful Operation . 11
5.1.2 Unsuccessful Operation . 12
5.1.3 Abnormal Conditions . 12
5.1.4 Overload . 12
5.2 Connection Oriented Information Transfer . 13
5.2.1 Successful Operation . 13
5.2.2 Abnormal Conditions . 13
5.2.3 Segmentation . 13
5.3 Connectionless Information Transfer . 14
5.3.1 Successful Operation . 14
5.3.2 Unsuccessful Operation . 14
5.3.3 Abnormal Conditions . 15
5.3.4 Segmentation . 15
5.4 LMU Connection Establishment . 15
5.4.1 LMU Connection Establishment initiated by the SMLC . 15
5.4.1.1 Successful Operation . 15
5.4.1.2 Unsuccessful Operation . 16
5.4.1.3 Abnormal Conditions . 16
5.4.2 LMU Connection Establishment initiated by the MSC . 16
5.4.2.1 Successful Operation . 16
5.4.2.2 Unsuccessful Operation . 16
5.4.2.3 Abnormal Conditions . 16
5.5 (void) . 17
5.6 DTAP-LE Information Transfer . 17
5.6.1 DTAP-LE Information Transfer Initiated by the SMLC . 17
5.6.2 DTAP-LE Information Transfer Initiated by the BSC . 17
5.7 Reset . 17
5.7.1 Normal Operation . 17
5.7.2 Abnormal Conditions . 17
5.8 Perform Location Information . 18
6 Usage of BSSAP-LE and BSSAP on the Lb Interface . 18
6.1 Applicable Message Sets . 18
6.2 MTP Functions . 19
6.3 SCCP Functions . 19
6.3.1 General . 19
6.3.2 Modifications for Connectionless SCCP . 20
6.3.3 Modifications for Connection Oriented SCCP . 20
6.3.4 Contents of the SCCP Data Field . 20
6.3.5 Abnormal Conditions . 21
7 (void) . 21
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8 Use of BSSAP-LE on the Lp Interface. 21
8.1 Applicable Message Sets . 21
8.2 MTP Functions . 21
8.3 SCCP functions . 22
8.3.1 General . 22
8.3.2 Allowed Exceptions to ITU-T Recommendations Q.711-714 . 22
8.3.3 Allowed Exceptions to ANSI T1.112 . 22
8.3.4 Usage of Connectionless SCCP . 22
8.3.5 Usage of Connection Oriented SCCP . 23
8.3.6 Contents of the SCCP Data Field . 23
9 Message Functional Definitions and Contents . 23
9.1 BSSMAP-LE PERFORM LOCATION REQUEST message . 24
9.1.1 Location Type . 24
9.1.2 Cell Identifier . 24
9.1.3 Classmark Information Type 3 . 24
9.1.4 LCS Client Type . 25
9.1.5 Chosen Channel . 25
9.1.6 LCS Priority . 25
9.1.6a LCS QoS . 25
9.1.7 Requested GPS Assistance Data . 25
9.1.8 BSSLAP APDU . 25
9.1.9 LCS Capability . 25
9.1.10 Packet Measurement Report . 25
9.1.11 Measured Cell Identity List . 25
9.1.12 IMSI . 25
9.1.13 IMEI. 25
9.1.14 GANSS Location Type . 25
9.1.15 Requested GANSS Assistance Data . 26
9.1.16 BSS Multilateration Capability . 26
9.1.17 Multilateration Timing Advance . 26
9.1.18 MS Sync Accuracy . 26
9.1.19 BTS Reception Accuracy Level . 26
9.1.20 Coverage Class . 26
9.2 BSSMAP-LE PERFORM LOCATION RESPONSE message . 26
9.2.1 Location Estimate . 26
9.2.2 Positioning Data . 26
9.2.3 Deciphering Keys . 27
9.2.4 LCS Cause . 27
9.2.5 Velocity Data . 27
9.2.6 GANSS Positioning Data . 27
9.3 BSSMAP-LE PERFORM LOCATION ABORT message . 27
9.3.1 LCS Cause . 27
9.4 (void) . 28
9.5 (void) . 28
9.6 (void) . 28
9.7 (void) . 28
9.8 BSSMAP-LE CONNECTION ORIENTED INFORMATION message . 28
9.8.1 BSSLAP APDU . 28
9.8.2 Segmentation . 28
9.8.3 Multilateration Positioning Method . 29
9.8.4 Cell Identifier . 29
9.8.5 Multilateration Timing Advance . 29
9.8.6 MS Sync Accuracy . 29
9.8.7 BTS Reception Accuracy Level . 29
9.8.8 Short ID . 29
9.8.9 Random ID. 29
9.9 BSSMAP-LE CONNECTIONLESS INFORMATION message . 29
9.9.1 Source Identity . 30
9.9.2 Destination Identity. 30
9.9.3 APDU . 30
9.9.4 Segmentation . 30
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9.9.5 Return Error Request . 30
9.9.6 Return Error Cause . 30
9.10 BSSMAP-LE RESET message . 30
9.11 BSSMAP-LE RESET ACKNOWLEDGE message . 31
9.12 BSSMAP-LE PERFORM LOCATION INFORMATION message . 31
9.12.1 Cell Identifier . 31
9.12.2 BSSLAP APDU . 31
9.13 BSSMAP-LE ASSISTANCE INFORMATION REQUEST message . 31
9.13.1 Serving Cell Identifier . 32
9.13.2 Cell Identity List . 32
9.13.3 Short ID Set . 32
9.13.4 Random ID Set . 32
9.14 BSSMAP-LE ASSISTANCE INFORMATION RESPONSE message . 32
9.14.1 Cell Information List . 32
9.14.2 Short BSS ID . 32
9.14.3 MTA Access Security Required . 32
10 Message format and information element coding . 33
10.1 Message type . 33
10.2 Information Element Identifiers . 34
10.3 APDU . 34
10.4 Cause . 35
10.5 Cell Identifier . 35
10.6 Chosen Cha nne l . 35
10.7 Classmark Information Type 3 . 36
10.8 Deciphering Keys . 36
10.9 Geographic Location . 36
10.10 Requested GPS Assistance Data . 37
10.11 IMSI . 39
10.12 (void) . 39
10.13 LCS Cause . 39
10.14 LCS Client Type . 40
10.15 LCS Priority . 41
10.16 LCS QoS . 41
10.17 (void) . 42
10.18 Location Type . 42
10.19 Network Element Identity . 43
10.20 Positioning Data . 44
10.21 Return Error Request . 45
10.22 Return Error Cause . 45
10.23 (void) . 46
10.24 Segmentation . 46
10.25 (void) . 47
10.26 LCS Capability . 47
10.27 Packet Measurement Report . 47
10.28 Cell Identity List . 47
10.29 IMEI . 48
10.30 Velocity Data . 48
10.31 Requested GANSS Assistance Data . 48
10.32 GANSS Positioning Data . 55
10.33 GANSS Location Type . 55
10.34 BSS Multilateration Capability IE . 56
10.35 Cell Information List IE . 56
10.36 BTS Reception Accuracy Level IE . 60
10.37 Multilateration Positioning Method IE . 62
10.38 Multilateration Timing Advance IE . 63
10.39 MS Sync Accuracy IE . 63
10.40 Short ID Set IE . 64
10.41 Random ID Set . 64
10.42 Short BSS ID IE . 65
10.43 Random ID . 65
10.44 Short ID IE . 65
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10.45 Coverage Class IE . 65
10.46 MTA Access Security Required (MTASR) IE . 66
Annex A (informative): Change history . 67
History . 68

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Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The present document defines the coding of information in an extension of the Base Station System Application Part
(BSSAP) that is needed to support location services on interfaces based on use of BSSAP.
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 procedures and information coding that are needed to define and support the BSSAP
LCS Extension (BSSAP-LE). The BSSAP-LE message set is applicable to the following GSM interfaces defined in
3GPP TS 43.059:
- Lb interface (BSC-SMLC).
- Lp interface (SMLC-SMLC).
The present document defines message formats and encoding for BSSAP-LE and the particular subsets of it that are
applicable to each of the above interfaces. The present document also defines the support for BSSAP-LE message
transfer on each of these interfaces using either ITU-T and ANSI versions of SS7 MTP or IETF M3UA/SCTP and
SCCP. Additional requirements for the above interfaces that are applicable to BSSAP-LE are also defined – e.g. usage
of BSSAP (as defined in 3GPP TS 24.008 and 48.008) on the Lb interface.
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".
[1a] 3GPP TS 23.032: "Universal Geographical Area Description (GAD)".
[2] 3GPP TS 43.059: "Functional Stage 2 Description of Location Services in GERAN".
[3] 3GPP TS 44.018: "Mobile radio interface layer 3 specification; Radio Resource Control Protocol".
[3a] 3GPP TS 24.008: "Mobile radio interface layer 3 specification; Core Network Protocols; Stage 3".
[4] 3GPP TS 44.031: "Location Services (LCS); Mobile Station (MS) – Serving Mobile Location
Center (SMLC); Radio Resource LCS Protocol (RRLP)".
[5] 3GPP TS 44.071: "Location Services (LCS); Mobile radio interface layer 3 Location Services
(LCS) specification".
[6] 3GPP TS 48.006: "Signaling transport mechanism specification for the Base Station Subsystem –
Mobile-services Switching Centre (BSS - MSC) interface".
[7] 3GPP TS 48.008: "Mobile-services Switching Centre – Base Station System (MSC-BSS)
interface; Layer 3 specification".
[8] 3GPP TS 48.031: "Location Services (LCS); Serving Mobile Location Center – Serving Mobile
Location Center (SMLC - SMLC); SMLCPP specification".
[9] 3GPP TS 48.071: "Serving Mobile Location Center – Base Station Subsystem (SMLC-BSS)
interface Layer 3 specification".
[10] 3GPP TS 29.002: "Mobile Application Part (MAP) specification".
[10a] 3GPP TS 23.003: "Numbering, addressing and identification".
[11] ITU-T Recommendation Q.702: "Signalling data link".
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[12] ITU-T Recommendation Q.703: "Signalling link".
[13] ITU-T Recommendation Q.704: "Signalling network functions and messages".
[14] ITU-T Recommendation Q.707: "Testing and maintenance".
[15] ITU-T Recommendation Q.711: "Functional description of the signalling connection control part".
[16] ITU-T Recommendation Q.712: "Definition and function of signalling connection control part
messages".
[17] ITU-T Recommendation Q.713: "Signalling connection control part formats and codes".
[18] ITU-T Recommendation Q.714: "Signalling connection control part procedures".
[19] ANSI T1.111 (1996): "Signalling System Number 7 – Message Transfer Part".
[20] ANSI T1.112 (1996): "Signalling System Number 7 (SS7) - Signalling Connection Control Part
Functional Description".
[21] TIA/EIA/IS-J-STD-036 (2000): "Wireless Enhanced Emergency Services".
[22] 3GPP TS 48.018: "General Packet Radio Service (GPRS); Base Station System (BSS) - Serving
GPRS Support Node (SGSN); BSS GPRS Protocol (BSSGP)".
[23] IETF STD 51, RFC 1661(07/1994): "The Point-To-Point Protocol (PPP)".
[24] IETF STD 51, RFC 1662(07/1994): "PPP in HDLC-like Framing".
[25] IETF RFC 2507(02/1999): "IP header compression".
[26] IETF RFC 1990(07/1994): "The PPP Multilink Protocol (MP)".
[27] IETF RFC 2686(09/1999): "The Multi-Class Extension to Multi-Link PPP".
[28] IETF RFC 2509(02/1999): "IP Header Compression over PPP".
[29] 3GPP TS 29.202: "SS7 Signalling Transport in Core Network; Stage 3".
[30] Galileo OS SIS ICD/D.0 "Galileo Open Service, Signal In Space Interface Control
Document/Draft 0".
[31] Global Navigation Satellite System GLONASS Interface Control Document, Version 5, 2002.
[32] BDS-SIS-ICD-B1I-1.0: "BeiDou Navigation Satellite System Signal In Space Interface Control
Document Open Service Signal B1I (Version 1.0)", December 2012.
3 Definitions, abbreviations and symbols
For the purposes of the present document, the definitions, symbols and abbreviations listed in 3GPP TS 21.905 and
3GPP TS 43.059 apply.
4 Definition of BSSAP-LE
BSSAP-LE is an extension to BSSAP that contains messages and parameters specific to the support of LCS. The
following subsets of BSSAP-LE are defined: DTAP-LE, BSSMAP-LE.
4.1 DTAP-LE Messages
DTAP-LE messages are transfered between an SMLC and a Type A LMU and comprise the following individual
messages:
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- REGISTER;
- FACILITY;
- RELEASE COMPLETE.
The content, encoding and certain procedures asssociated with DTAP-LE messages are defined in 3GPP TS 44.071.
4.2 BSSMAP-LE Messages
BSSMAP-LE messages are transferred between a BSS and SMLC and comprise the following individual messages:
BSSMAP-LE Positioning Messages:
- Perform Location Request;
- Perform Location Response;
- Perform Location Abort;
- Perform Location Information.
BSSMAP-LE Information Messages:
- Connection Oriented Information;
- Connectionless Information.
BSSMAP-LE General Messages:
- Reset;
- Reset Acknowledge.
The content and encoding of BSSMAP-LE messages are defined in the present document.
5 Procedures applicable to use of BSSAP-LE
5.1 Location Request
The Location Request procedure is applicable to the Lb interface. Its purpose is to obtain a location estimate for a target
MS that is already in dedicated mode, in packet transfer mode, in packet idle mode, or in dual transfer mode. It is also
used to provide an MS with LCS assistance data or with a deciphering key for LCS broadcast assistance data. The
initiator of a location request is the BSS. The procedure makes use of SCCP connection oriented signaling on the Lb
interface.
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5.1.1 Successful Operation
The initiator of the location request sends a BSSMAP-LE Perform Location Request to the SMLC associated with the
current serving cell for the target MS. The message contains the following mandatory (M), conditional (C) and optional
(O) information, where conditional parameters are required if available.
- Location Type (M).
- GANSS Location Type (C)
- Cell Identifier (M).
- Classmark Information Type 3 (C).
- LCS Client Type (C).
- Chosen Channel (C).
- LCS Priority (C).
- LCS QoS (C).
- Requested GPS Assistance Data (C).
- BSSLAP APDU (C).
- LCS Capability (O).
- Packet Measurement Report (O).
- Measured Cell Identity List (O).
- IMSI of target MS (O).
- IMEI of target MS (O).
- Requested GANSS Assistance Data (C).
If requested, the SMLC performs positioning of the target MS using a particular position method or a combination of
more than one positioning method. If neither the Classmark Information Type 3 IE nor the LCS Capability IE is present,
the SMLC shall instigate only network based positioning methods (e.g. TA and U-TDOA but not GPS or E-OTD).
Alternatively, if requested otherwise, the SMLC may provide positioning assistance data to the MS. The SMLC may
invoke the following other BSSAP-LE procedures to perform these procedures:
- connection oriented information transfer;
- connectionless information transfer;
- LMU connection establishment;
- LMU connection release;
- DTAP-LE information transfer.
Additional procedures defined in 3GPP TS 24.008 and 3GPP TS 48.008 may also be performed. If a location estimate
was requested and was subsequently obtained, the SMLC shall return a BSSMAP-LE Perform Location Response to the
initiator of the location request. This message contains the following mandatory, conditional and optional parameters.
- Location Estimate (M).
- Positioning Data (C).
- GANSS Positioning Data (C).
Restrictions on the geographic shape encoded within the Location Estimate parameter may exist for certain LCS client
types. The SMLC shall comply with any restrictions defined in 3GPP specifications and, in a particular country, with
any restrictions defined for a specific LCS client type in relevant national standards. For example, in the US, national
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interim standard TIA/EIA/IS-J-STD-036 [21] restricts the geographic shape for an emergency services LCS client to
minimally either an "ellipsoid point" or an "ellipsoid point with uncertainty circle and confidence" as defined in
3GPP TS 23.032.
If assistance data was instead requested for an MS and the SMLC was able successfully to transfer this to the M
...