ETSI TS 102 650 V1.1.1 (2008-07)

Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Analysis of Location Information Standards produced by various SDOs

DTS/TISPAN-03048-EMTEL

General Information

• Status: Published
• Publication Date: 30-Jul-2008
• Technical Committee: TISPAN 3 - TISPAN Protocols
• Current Stage: 12 - Completion
• Due Date: 06-Aug-2008
• Completion Date: 31-Jul-2008

Standards Content (Sample)

Technical Specification
Telecommunications and Internet converged Services and
Protocols for Advanced Networking (TISPAN);
Analysis of Location Information Standards
produced by various SDOs
2 ETSI TS 102 650 V1.1.1 (2008-07)

Reference
DTS/TISPAN-03048-EMTEL
Keywords
Emergency, location
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3 ETSI TS 102 650 V1.1.1 (2008-07)
Contents
Intellectual Property Rights.6
Foreword.6
Introduction .6
1 Scope.8
2 References.8
2.1 Normative references.8
2.2 Informative references.10
3 Definitions and abbreviations.11
3.1 Definitions.11
3.2 Abbreviations.13
4 Introduction .16
4.1 Emergency Response Principles.16
4.2 One emergency call number.16
4.3 Service specific emergency call numbers.17
4.4 Use of the Location Information .18
4.4.1 Call routing.18
4.4.2 Dispatching.19
4.4.3 Locating.19
4.5 Location Information.19
4.5.1 Geodetic locating information .20
4.5.1.1 X and Y coordinates.20
4.5.1.2 Z coordinate.20
4.5.2 Civic locating information .21
4.6 Coding principles for location information .22
4.6.1 Specific field definitions.22
4.6.2 Rigorously structured field definitions .23
4.6.3 Loosely structured field definitions .25
4.6.4 Comparison of field definitions .26
4.7 Conversion of location information.26
4.7.1 Geodetic to map.26
4.7.2 Geodetic to area .26
4.7.3 Geodetic to civic .27
4.7.4 Civic to geodetic .27
4.7.5 Civic to map and civic to area.27
5 Categories of impact on location information.27
5.1 Mobility.27
5.2 UE attachment.28
5.3 CPN Architecture.28
5.4 Location information.32
6 Cascading networks.33
6.1 Direct attachment to NGN access networks .33
6.2 Attachment of an NGCN to an access network.34
6.3 Cascaded NGCN.35
6.4 Location acquisition protocol and Proxy LIS querying.35
6.5 The problem of the tunnel .37
7 Handling of emergency sessions in 3GPP.38
7.1 Architecture.38
7.2 User equipment (UE).38
7.2.1 Requirements.38
7.2.2 Emergency session establishment request .39
7.3 IMS Functional entities .39
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4 ETSI TS 102 650 V1.1.1 (2008-07)
7.3.1 Proxy Call Server Control Function (P-CSCF).39
7.3.2 Emergency Call Server Control Function (E-CSCF).40
7.3.3 Location Retrieval Function (LRF) .40
7.4 Procedures for IMS Emergency Services (Overview).41
7.4.1 Procedures without Location Retrieval Function (LRF).41
7.4.2 Procedures involving the Location Retrieval Function (LRF).41
7.4.3 Acquiring location information from the UE and/or the network.42
8 The IETF, NENA, ATIS Approach.43
8.1 Abstract.43
8.2 Introduction/Executive Summary.43
8.3 NENA «i2» Architecture.44
8.4 Location Determination in Broadband Access Networks.44
8.5 LIS Operational Considerations.45
8.6 Location Acquisition Protocols.46
8.7 Location Parameter Conveyance.47
9 Comparison between 3GPP and NENA.47
10 Developments in Europe (EU) .47
10.1 The CGALIES survey - Excerpt from Final Report.48
10.1.1 Type of areas.48
10.1.2 Type of information.48
10.1.3 Use of the Location Information.49
10.1.4 Accuracy.49
10.2 Developments in the UK .49
10.2.1 Background.49
10.2.2 Progress.50
10.3 Developments in Germany (Core IMS Emergency Calling Architecture).50
10.3.1 Introduction.50
10.3.2 Description of the DT Core IMS Emergency Calling Architecture (for DSL-access).51
10.3.2.1 Step 1.51
10.3.2.2 Step 2.52
10.3.3 Proposal for a Harmonized International Emergency Calling Architecture (NENA «i2», 3GPP IMS
and DT Core IMS).53
10.3.4 Additional Requirements to the TISPAN Emergency Calling Architecture.54
10.3.4.1 NENA «i2» architecture drawbacks.54
10.3.4.2 Requirements to the TISPAN Emergency Calling Architecture .55
11 Developments in North America.55
12 Developments in Australia .55
12.1 Location information options .55
12.2 Supplementary comments on the options.56
12.3 Potential barriers to adoption.56
12.4 The role of the access network(s).57
12.4.1 The NGN access network .57
12.4.2 The NGCN access network.57
12.5 Alignment of activity with International Standards Developments.58
13 Developments in the Far East.58
13.1 Developments in Japan.58
13.1.1 Introduction.58
13.1.2 Emergency numbers .59
13.1.3 IP Telephony Requirements for Emergency Calls.59
13.1.3.1 Basic requirements.59
13.1.3.2 Acquiring and presenting geographical location information .60
13.1.4 Japanese address code for location information.61
13.2 Other developments.62
14 Problems solved and unsolved .62
14.1 Problems solved.62
14.1.1 NGCN with Location Acquisition Protocol.62
14.1.2 Cascading networks .63
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5 ETSI TS 102 650 V1.1.1 (2008-07)
14.1.3 Geodetic or civic location information .63
14.1.4 Conversions from geodetic to civic addresses are country specific.63
14.1.5 From TDM based to IP based NGN emergency communication .63
14.2 Problems unsolved.64
14.2.1 GNSS receipt inside buildings or tunnels .64
14.2.2 "Tree and Branch" scenarios.64
14.2.3 VPN tunnels.64
14.2.4 Accuracy of location information in the LIS .64
Annex A (informative): Recommendation of the Commission (2003/558/EC) .65
A.1 Considerata.65
A.2 Recommendation.66
Annex B (informative): List of Technology Recommendations .68
B.1 Location information format .68
B.2 Location information acquisition protocol .68
B.3 Signalling/transfer of location information .68
B.4 Related Conventions/Standards.68
Annex C (informative): URLs and References .69
C.1 Organizations.69
C.2 Documents.69
Annex D (informative): Location determination without GNSS.70
D.1 Self-Organizing position determination in Ad-Hoc networks.70
D.1.1 Step 1 - Time synchronization.70
D.1.2 Step 2 - Local coordinate system.70
D.1.3 Step 3 - Network coordinate system.72
D.1.4 The anchor and the seed .74
D.1.5 Bibliography for annex D.76
D.2 WLAN Positioning System.76
D.2.1 System Operation.76
D.2.2 Application.77
D.2.3 Key Differences.77
D.2.3.1 Cost and Simplicity.77
D.2.3.2 Availability .77
D.2.3.3 Reliability.78
D.2.3.4 Accuracy.78
D.2.3.5 Speed.78
D.2.3.6 Hybrid Operation.78
D.2.4 Note of Caution!.78
Annex E (informative): Bibliography.79
History .80

ETSI
6 ETSI TS 102 650 V1.1.1 (2008-07)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
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
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Telecommunications and Internet
converged Services and Protocols for Advanced Networking (TISPAN).
Introduction
The present document has been produced by an ETSI STF co-funded by EC/EFTA to examine the work of various
Standards Development Organizations worldwide in developing and implementing protocols for the transmission of
location information over telecommunications networks for use in establishing the location of users of the emergency
calling facilities. In order to effectively deliver emergency services to the location of a reported incident, it is essential
for the emergency response organization to have timely and accurate information that enables them to correctly identify
the location of the incident.
The ability to initiate an emergency communication to summon help when needed is regarded by the European
Commission as a right of all citizens and this ability should ideally be independent of the network and access
technologies deployed or the physical abilities of the citizen.
The rights of individual users to privacy shall be adhered to according to European regulations and it is therefore
essential that all information derived from emergency calls shall only be used for management of the related incident. If
applied to non-emergency calls, the use of caller location information for commercial purposes may also be subject to
European or national regulation.
In many circumstances, citizens reporting an incident requiring urgent assistance are unable to provide the emergency
service with accurate information about the location of the emergency. This may be due either due to the nature of the
emergency, the callers' lack of local knowledge, their disabilities or lack of linguistic ability, etc. Young children or
cognitively impaired people may not have the language skills to explain their location, speech and/or hearing impaired
users may not be able to use voice terminals, visually impaired or otherwise disabled people may not be able to use text
terminals, elderly or confused people may not be able to use any form of terminal, etc. For these significantly large
categories of users the successful outcome of an emergency call could make the difference between life and death. It is
therefore essential for the emergency responders to be provided with accurate location information via an automated
process based on the communications network being used by the caller.
Implementation of caller location systems is also likely to result a welcome positive impact on the reduction of
malicious calls made by criminal or anti-social persons when they realize that the automatic provision of their location
information to the emergency services could enable their almost instant apprehension.
The present document should be read in conjunction with TS 102 660 [19] which reports on the Signalling
Requirements and Signalling Architecture for Supporting the Various Location Information Protocols for Emergency
Service on a NGN. The object of this work was to determine what, if any, standards existed and had been adopted for
signalling details of an emergency caller's location, in order to assist in the response to emergency calls.
It should be recognized that in the present document all references implying that 911 is the common emergency calling
number are used only to identify pre-existing work and as part of the titles of other documents. The mandated common
European emergency number is 112 with many countries also operating national numbers in parallel.
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7 ETSI TS 102 650 V1.1.1 (2008-07)
The present document does not contain a fully detailed technical analysis of location information standards but
concentrates on the background information and the ongoing activities by the various standards bodies in different
regions. It should be borne in mind that the document is intended to be focussed on what EC/EFTA wanted from their
contract, essentially to understand what the work is and what needs to be done. It is for TISPAN to do the in depth
analysis and produce the detailed technical recommendations.
ETSI
8 ETSI TS 102 650 V1.1.1 (2008-07)
1 Scope
The present document represents an analysis of the work done by various ETSI work groups and other standards bodies
worldwide on the acquisition and transmission of caller location information in various communications network types.
It also contains information about the protocols used and of any known deployments for the location of users making
emergency calls. It is not intended to examine the detailed workings of the protocols described or their possible use in
other communications network types.
The document does not mandate any new requirements but does report on the normative requirements from other
standards and regulatory bodies. It also refers, in part, to operating methods and national regulations in various
jurisdictions but does not intend to endorse these as requirements.
The hypothetical accuracy of the caller location and the accuracy achieved by the assessing methods are also
documented. Alternative methods for the coding of the emergency location information are also examined.
The present document also indicates a number of scenarios where location information may not be available or may be
inaccurate to various degrees and may suggest solutions for improvement.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably,
the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the
reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the
method of access to the referenced document and the full network address, with the same punctuation and use of upper
case and lower case letters.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] ETSI TS 123 167 (V7.6.0): "Universal Mobile Telecommunications System (UMTS); IP
Multimedia Subsystem (IMS) emergency sessions (3GPP TS 23.167 version 7.6.0 Release 7).
[2] ETSI TS 123 041 (V3.5.0): "Digital cellular telecommunications system (Phase 2+);Universal
Mobile Telecommunications System (UMTS);Technical realization of Cell Broadcast Service
(CBS) (3GPP TS 23.041 version 3.5.0 Release 1999)".
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9 ETSI TS 102 650 V1.1.1 (2008-07)
[3] ETSI ES 282 004: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); NGN Functional Architecture; Network Attachment
Sub-system (NASS)".
[4] NENA «I2» architecture: "Interim VoIP Architecture for Enhanced 9-1-1 Services («i2»)".
NOTE: Available at http://www.nena.org/media/File/NENA_08-001_V1_12-06-05_1.pdf.
[5] ISO 3166-1(2006): "Codes for the representation of names of countries and their subdivisions --
Part 1: Country codes".
[6] NIMA Technical Report TR8350.2: "Department of Defence World Geodetic System 1984, Its
Definition and Relationships With Local Geodetic Systems"; Third Edition; National Imagery and
Mapping Agency, 4 July 1997.
[7] IETF RFC 3046: "DHCP Relay Agent Information Option".
[8] IETF RFC 3825: "Dynamic Host Configuration Protocol Option for Coordinate-based Location
Configuration Information".
[9] IETF RFC 4776: "Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Option for
Civic Addresses Configuration Information".
[10] IETF RFC 4119: "A Presence-based GEOPRIV Location Object Format".
[11] Coordination Group on Access to Location Information by Emergency Services (CGALIES):
"Final Report V1.0".
NOTE: Available at http://ec.europa.eu/environment/civil/pdfdocs/cgaliesfinalreportv1_0.pdf and
http://portal.etsi.org/docbox/STF/STF321_TISPAN3_EC_Emergency_Call_Location/Public/Library/EC
%20Documents/cgalies_final.pdf.
[12] IP Location Information/04/006 V2 16Jan07: "Report from the IP Location Information Working
Group".
[13] draft-arai-ecrit-japan-req-01: "Emergency Call Requirements for IP Telephony Services In Japan".
[14] 2003/558/EC (25 July 2003): "Commission Recommendation on the processing of caller location
information in electronic communication networks for the purpose of location-enhanced
emergency call services" (notified under document number C(2003) 2657 [i.5]).
NOTE: This recommendation is replicated in annex A of the present document.
[15] ETSI TR 180 000: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); NGN Terminology".
[16] ETSI TS 123 271: " Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); Functional stage 2 description of Location Services (LCS)
(3GPP TS 23.271)".
[17] ATIS Technical Report: "Location Acquisition and Location Parameter Conveyance for Internet
Access Networks in Support of Emergency Services".
[18] GEOPRIV L7LCP: draft-ietf-geopriv-l7-lcp-ps-07.txt.
[19] ETSI TS 102 660: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Signalling Requirements and Signalling Architecture for
supporting the various location information protocols for Emergency Service on a NGN".
[20] DCITA report: " Examination Of Policy And Regulation Relating to Voice Over Internet Protocol
(VoIP) Services - Report To The Minister For Communications, Information Technology And The
Arts ".
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10 ETSI TS 102 650 V1.1.1 (2008-07)
2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
[i.1] "GPS-free positioning in mobile Ad-Hoc networks", Cluster Computing, 5(2), April 2002. Srdan
Čapkun, Maher Hamdi, Jean-Pierre Hubaux.
[i.2] "Towards Mobile Ad-Hoc WANs: Terminodes", J.-P. Hubaux, J.-Y. Le Boudec, S. Giordano,
M. Hamdi, L j. Blazevic, L . Buttyan and M. Vojnovic. IEEE WCNC, September 2000.
[i.3] "Location aided routing (LAR) in mobile ad-hoc networks", Y.B. Ko and N.H. Vaidya,
MOBICOM, 1998.
[i.4] "Self-Organizing Wide-Area routing", Lj. Blazevic, S. Giordano and J. Y. Le Boudec,
SCI 2000/ISAS 2000, Orlando, July 2000.
[i.5] C(2003)2657 25 (July 2003): "Commission Recommendation of the processing of caller location
information in electronic communication networks for the purpose of location-enhanced
emergency call services".
[i.6] AS/NZS 4819:2003: "Geographic information - Rural and urban addressing". .
NOTE: Plus draft DR 05191 CP: Amendment 1 to AS/NZS 4819:2003.
NOTE: Australian Standards are available from: http://www.saiglobal.com/shop/Script/Provider.asp?Db=AS.
[i.7] IETF RFC 3693: "Geopriv Requirements".
[i.8] IETF RFC 4676: "Dynamic Host Configuration Protocol Option for Civic Addresses
Configuration Information".
NOTE: IETF RFCs are available from: http://www.ietf.org/.
[i.9] NENA: "NENA VoIP Recommended Methods for Determining Location to Support Emergency
Calling Technical Information Document (TID)".
NOTE: Available from: http://www.nena.org/media/files/08-505_20061221.pdf.
NOTE: Available from: http://www.3gpp.org/ftp/Specs/html-info/23167.htm.
[i.10] Directive 2002/21/EC on a common regulatory framework for electronic communications and
services (the "Framework Directive") (OJ L 108, 24.4.2002).
[i.11] COUNCIL DECISION of 29 July 1991 on the introduction of a single European emergency call
number (91/396/EEC). (OJ L 217, 6.8.1991).
[i.12] Directive 2002/22/EC on universal service and users' rights relating to electronic communications
networks and services (the "Universal Service Directive") (OJ L 108, 24.4.).
[i.13] Directive 2002/58/EC concerning the processing of personal data and the protection of privacy in
the electronic communications sector (the "Directive on privacy and electronic communications")
(OJ L 201, 31.7.2002).
[i.14] ETSI TS 123 167: "Universal Mobile Telecommunications System (UMTS); IP Multimedia
Subsystem (IMS) emergency sessions (3GPP TS 23.167 version 7.9.0 Release 7)".
[i.15] ETSI EN 300 403: "Integrated Services Digital Network (ISDN); Digital Subscriber Signalling
System No. one (DSS1) protocol; Signalling network layer for circuit-mode basic call control;
Part 1: Protocol specification [ITU-T Recommendation Q.931 (1993), modified]".
[i.16] ETSI TS 124 008: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); Mobile radio interface Layer 3 specification; Core network
protocols; Stage 3 (3GPP TS 24.008 version 7.12.0 Release 7)".
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11 ETSI TS 102 650 V1.1.1 (2008-07)
[i.17] ITU-T Recommendation Q.931: "ISDN user-network interface layer 3 specification for basic call
control".
[i.18] DR 05191 CP: "Amendment 1 to AS/NZS 4819:2003 - Geographic information - Rural and urban
addressing".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
access network: portion of the Telecommunications Network that provides access to the switching function and
terminates the User Access signalling
NOTE 1: In a PLMN this is a radio access via a Base Station.
NOTE 2: c.f. (ITU-T Recommendation Q.931 [i.17], EN 300 403 [i.15], TS 124 008 [i.16]).
disaster: serious disruption of the functioning of society, posing a significant, widespread threat to human life, health,
property or the environment, whether caused by accident, nature or human activity, and whether developing suddenly or
as the result of complex, long-term processes
disaster mitigation: measures designed to prevent, predict, prepare for, respond to, monitor and/or reduce the impact
of, disasters
emergency: urgent need for assistance or relief
emergency call: call from a user to an emergency call centre, PSAP or similar agency charged with routing calls to the
relevant emergency response organization
emergency call facilities: mechanisms provided by public or private communications networks, emergency telephone
stanchions/boxes, fire alarms, etc. the use of which enables emergency calls to be made
emergency call service: mechanism by which a caller is given a fast and easy means of giving information about an
emergency situation to the appropriate emergency organization (e.g. fire department, police, ambulance)
emergency caller: user who calls an emergency service by making an emergency call
emergency control centre: facilities used by emergency organizations used to accept and handle emergency calls
forwarded from a PSAP
emergency number: special short code or number which is used to provide callers with immediate access to the PSAP
to request assistance from the emergency services
NOTE: There are two different types of emergency numbers in Europe:
- European emergency number, 112: unique emergency number for pan-European and GSM emergency
services and used, for example, in EU member-states, Switzerland and other countries.
- National emergency numbers: each country may also have its own national emergency number and/or
one or more numbers for alerting specific services.
emergency response organization: local or national force established to prvide assistance to citizens in the event of
their being involved in an emergency situation and requiring specialised help, for example, the police, fire service and
emergency medical services
emergency service: service that provides immediate and rapid assistance in situations where there is a direct risk to life
or limb, individual or public health or safety, to private or public property, or the environment but not necessarily
limited to these situations (Recommendation 2003/558/EC [14] and C(2003)2657 [14])
emergency situation: abnormal situation of serious nature that develops suddenly and unexpectedly, of which the
evolution is uncertain and which may turn into a crisis or cause damage and casualties
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12 ETSI TS 102 650 V1.1.1 (2008-07)
enhanced 112 (E112): emergency communications service using the single European emergency call number, 112,
which is enhanced with location information of the calling user (Recommendations 2003/558/EC [14] and
C(2003)2657 [i.5])
enhanced 911 (E911) wireless service: a network based system that associates a physical address with the calling
party's telephone number and routes the call to the most appropriate Public Safety Answering Point (PSAP) for that
address, thus providing emergency call-takers with the location of the emergency without the person calling for help
having to provide it
NOTE Wireless E911 program (in North America) is divided into two parts:
- Phase I requires carriers, upon valid request by a local Public Safety Answering Point (PSAP), to report
the telephone number of a wireless 911 caller and the location of the antenna that received the call.
- Phase II requires wireless carriers to provide far more precise location information, within 50 metres to
300 metres in most cases.
health hazard: a sudden outbreak of infectious disease, such as an epidemic or pandemic, or other event posing a
significant threat to human life or health, which has the potential for triggering a disaster
geoid: equi-potential surface of the Earth's gravity field which best fits, in a least squares sense, global mean sea level
location acquisition: process of a client device or application requesting
...