ETSI TR 103 201 V1.1.1 (2016-03)

Emergency Communications (EMTEL); Total Conversation for emergency communications; implementation guidelines

DTR/EMTEL-00029

General Information

• Status: Published
• Publication Date: 13-Mar-2016
• Technical Committee: EMTEL - Emergency Communications
• Current Stage: 12 - Completion
• Due Date: 15-Mar-2016
• Completion Date: 14-Mar-2016

Standards Content (Sample)

TECHNICAL REPORT
Emergency Communications (EMTEL);
Total Conversation for emergency communications;
implementation guidelines
2 ETSI TR 103 201 V1.1.1 (2016-03)

Reference
DTR/EMTEL-00029
Keywords
accessibility, disability, emergency, IMS, IP, real-
time text, SIP, total conversation

ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the
print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying
and microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© European Telecommunications Standards Institute 2016.
All rights reserved.
TM TM TM
DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.
TM
3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.
ETSI
3 ETSI TR 103 201 V1.1.1 (2016-03)
Contents
Intellectual Property Rights . 7
Foreword . 7
Modal verbs terminology . 7
Introduction . 7
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 8
3 Definitions and abbreviations . 12
3.1 Definitions . 12
3.2 Abbreviations . 13
4 Background . 14
5 Existing requirements, recommendations, and assumptions . 15
5.1 General . 15
5.2 Summary of existing requirements . 15
5.3 Study and Analysis Assumptions . 16
5.3.1 General . 16
5.3.2 Assumptions related to Total Conversation for Emergency Communication . 16
5.3.3 Assumptions about the PSAP and Relay node networks . 17
5.3.4 Assumptions about the Total Conversation user terminal and access network . 17
5.3.5 Assumptions on the routing of Total Conversation for emergency communication calls . 17
6 Architecture principles . 17
6.1 General . 17
6.2 Functional Architecture . 17
6.3 Call scenarios . 19
6.3.1 General . 19
6.3.2 Baseline session (without any assisting service) . 19
6.3.3 Routing based on media capability of PSAP . 19
6.3.4 Routing based on language / modality . 19
6.3.5 Routing via an assisting service . 20
6.3.6 Conferencing with third party including assisting relay services. 20
6.3.7 Transfer of session from PSAP . 20
6.3.8 Transfer of session to more appropriate Total Conversation user terminal . 21
6.3.9 Call-back . 21
6.4 Implementation technologies. 22
6.4.1 General . 22
6.4.2 IETF SIP . 22
6.4.3 IMS . 22
6.4.4 Web based technologies . 22
6.4.5 PSTN . 22
6.5 Supported functions in Total Conversation for Emergency Communications . 22
6.5.1 General . 22
6.5.2 Identification of the Total Conversation emergency session . 23
6.5.3 Naming and addressing . 23
6.5.3.1 Caller / Originator Identity . 23
6.5.3.2 Relay Service identification and addressing . 23
6.5.4 Language considerations . 24
6.5.5 Location and routing . 24
6.5.5.1 Location information . 24
6.5.5.2 Routing information . 25
6.5.6 Assisting services . 25
6.5.7 Security and Privacy . 26
6.5.8 Transfer of session to another Total Conversation user terminal . 27
ETSI
4 ETSI TR 103 201 V1.1.1 (2016-03)
6.5.9 Testing . 27
6.5.10 Media . 27
7 Key Issues for implementing Total Conversation for Emergency services . 28
7.1 General . 28
7.2 Identification and invocation of assisting relay service . 28
7.2.1 General . 28
7.2.2 Issue #1: Invoking the conference for inclusion of an assisting relay service . 28
7.2.2.1 General . 28
7.2.2.2 Solution #1: Conference invocation by the Total Conversation terminal . 29
7.2.2.2.1 Description . 29
7.2.2.2.2 Evaluation . 29
7.2.2.3 Solution #2: Conference invocation initiated in the Access Network . 30
7.2.2.3.1 Description . 30
7.2.2.3.2 Evaluation . 31
7.2.2.4 Solution #3: Conference invocation in the ESInet . 32
7.2.2.4.1 Description . 32
7.2.2.4.2 Evaluation . 32
7.2.3 Issue #2: Indicating/identifying the communication needs of the Total Conversation user. 33
7.2.3.1 General . 33
7.2.3.2 Solution #1: Preferred Language / Modality indicated by Total Conversation terminal in Accept-
Contact header . 33
7.2.3.2.1 Description . 33
7.2.3.2.2 Evaluation . 34
7.2.3.3 Solution #2: Preferred Language / Modality indicated by Total Conversation terminal in SDP
language attribute . 34
7.2.3.3.1 Description . 34
7.2.3.3.2 Evaluation . 35
7.2.3.4 Solution #3: Preferred Language / Modality tag added by Application Service Provider . 35
7.2.3.4.1 Description . 35
7.2.3.4.2 Evaluation . 36
7.2.3.5 Solution #4: Use of Additional Data to indicate communication needs and / or a specific relay
service . 36
7.2.4 Issue #3: Emergency session handling at the assisting relay service . 37
7.2.4.1 General . 37
7.2.4.2 Solution #1: Use of "SIP PSAP callback indicator" . 37
7.2.4.2.1 Description . 37
7.2.4.2.2 Evaluation . 37
7.2.4.3 Solution #2: Use of assisting relay service emergency specific URI . 38
7.2.4.3.1 Description . 38
7.2.4.3.2 Evaluation . 38
7.2.4.4 Solution #3: Trusted relay services recognizing PSAP specific originating URIs . 38
7.2.4.4.1 Description . 38
7.2.4.4.2 Evaluation . 38
7.2.4.5 Solution #4: include a SIP field in the call to use for assisting relay service invocation . 38
7.2.4.5.1 Description . 38
7.2.4.5.2 Evaluation . 38
7.2.4.6 Solution #5: include a SIP priority tag in the call to the assisting relay service to indicate its
emergency status . 39
7.2.4.6.1 Description . 39
7.2.4.6.2 Evaluation . 39
7.2.5 Issue #4: Obtaining the identity of a specific assisting service . 39
7.2.5.1 General . 39
7.2.5.2 Solution #1: PSAP interrogation of a database . 39
7.2.5.2.1 Description . 39
7.2.5.2.2 Evaluation . 40
7.2.5.3 Solution #2: Identity communicated by the Total Conversation user terminal . 40
7.2.5.3.1 Description . 40
7.2.5.3.2 Evaluation . 41
7.2.6 Issue #5: Total Conversation user default behaviour . 41
7.3 Automatic translation . 42
7.3.1 General . 42
ETSI
5 ETSI TR 103 201 V1.1.1 (2016-03)
7.3.2 Solution #1: Automatic translation at the PSAP . 42
7.3.2.1 Description . 42
7.3.2.2 Evaluation . 43
7.3.3 Solution #2: Automatic translation at the Total Conversation user terminal . 43
7.3.3.1 Description . 43
7.3.3.2 Evaluation . 44
7.4 Media . 44
7.4.1 General . 44
7.4.2 Video . 45
7.4.3 Audio . 45
7.4.4 Real-time text . 45
7.4.4.1 General . 45
7.4.4.2 Multi-party handling of real-time text . 46
8 Recommendations . 46
8.1 General . 46
8.2 Assisting services . 46
8.3 Roaming sessions routed via the home network. 48
8.4 Media . 48
8.5 Security . 50
9 Recommended updates and new specification work . 50
9.1 Gap analysis and remedial actions . 50
9.1.1 Use of terms GTT and RTT in 3GPP specifications . 50
9.1.1.1 Description of issue . 50
9.1.1.2 Remedial action . 50
9.1.1.3 Status . 50
9.1.2 Order of payload types for real-time text in 3GPP specifications . 50
9.1.2.1 Description of issue . 50
9.1.2.2 Remedial action . 51
9.1.2.3 Status . 51
9.1.3 Provision of feedback and comments on draft version ETSI ES 202 975 . 51
9.1.3.1 Description of issue . 51
9.1.3.2 Remedial action . 51
9.1.3.3 Status . 51
9.1.4 Inclusion of Total Conversation for emergency services as a regional requirement. 51
9.1.4.1 Description of issue . 51
9.1.4.2 Remedial action . 52
9.1.4.3 Status . 52
9.2 New and revised specifications . 52
9.2.1 General . 52
9.2.2 3GPP/ETSI specifications . 52
9.2.2.1 Relay service interface for emergency communications . 52
9.2.2.2 Test Specifications for Total Conversation . 52
9.2.2.3 AT commands . 52
9.2.2.4 ETSI TS 101 470 . 52
9.2.3 IETF specifications . 52
9.2.3.1 Best practices in real-time text . 52
9.2.4 EENA Specifications . 53
9.2.4.1 SDP based routing . 53
9.3 Open issues . 53
9.3.1 Use of non-usual terminals . 53
9.3.2 Configuration of Total Conversation settings . 53
9.3.2.1 General . 53
9.3.2.2 Setting by Application Service Provider . 53
9.3.2.3 Setting of the Total Conversation Terminal . 53
9.3.3 Rapid captioning of speech . 54
10 Conclusions . 54
Annex A: Alternative solution for relay service identification and invocation . 55
A.1 General . 55
ETSI
6 ETSI TR 103 201 V1.1.1 (2016-03)
A.2 Hybrid solution rationale . 55
A.2.1 Sessions where the Total Conversation user terminal is IETF or IMS SIP registered . 55
A.2.1.1 Sessions where the Total Conversation user terminal is not roaming . 55
A.2.1.2 Sessions where the Total Conversation user terminal is roaming . 55
A.2.2 Sessions where the Total Conversation user terminal is IMS emergency registered . 56
A.2.3 Example call-flow . 56
Annex B: Outstanding issues from ETSI TS 101 470 (V1.1.1) . 59
B.1 General . 59
B.2 Analysis of issues regarding ETSI TS 101 470 (V1.1.1) . 59
B.2.1 Text related to clause "5.4.2.1 Relay service" . 59
B.2.2 Text related to clause "5.4.2.1.2 IMS support" . 59
B.2.3 Text related to clause "5.4.3 Multi-party multi-media call" . 59
B.2.4 Text related to clause "5.4.4 Transfer and Forward supplementary services" . 59
B.2.5 Text related to clause "5.11.1 Basic SIP support" . 59
B.2.6 Text related to clause "5.17.1 Basic SIP support" . 60
Annex C: Existing IMS requirements for support of Total Conversation. 61
C.1 General . 61
C.2 Requirements from ETSI TS 122 101 . 61
C.2.1 General . 61
C.2.2 Requirements in clause 7.2 of ETSI TS 122 101. 61
C.2.3 Requirements in clause 7.2.4 of ETSI TS 122 101 . 61
C.2.4 Requirements in clause 10.4 of ETSI TS 122 101 . 62
C.3 Requirements from ETSI TS 122 173 . 63
C.4 Requirements from ETSI TS 126 114 . 64
C.5 Requirements from ETSI TS 122 228 . 64
C.6 Requirements from ETSI TS 123 167 . 64
Annex D: Current situation in Europe for Total Conversation and emergency service access
for persons with disabilities . 66
D.1 General . 66
D.2 Total Conversation, RTT and subsets for everyday use . 66
D.3 Relay service availability . 66
D.4 Emergency service access . 66
D.5 Conclusion . 67
History . 68

ETSI
7 ETSI TR 103 201 V1.1.1 (2016-03)
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 (https://ipr.etsi.org/).
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 Report (TR) has been produced by ETSI Special Committee Emergency Communications (EMTEL).
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Introduction
The present document contains recommendations and guidelines on the implementation of Total Conversation for
emergency service access and provision. Total Conversation enables conversation in real-time text, video and audio.
Subsets are also considered including the combination of real-time text and audio that forms the text telephony service.
Total Conversation services and terminals are deployed in some European countries, and have been adopted by people
with disabilities who, for example, need video for sign language, or real-time text for a text based conversation or as
complement to a voice conversation. The use of Total Conversation for Emergency Communications would enable
and/or improve access to emergency services by people with disabilities. However the few deployments of Total
Conversation for Emergency Communications that exist, are implemented in different ways in different countries, and
are not implemented according to the latest development of ETSI, IETF and 3GPP standards for Emergency
Communications. This non-harmonized deployment means that there are no interoperable solutions for emergency
service access across the EU countries, which is contrary to EU policy.
The present document is intended to assist ETSI SC EMTEL to coordinate with other standards bodies and relevant
stakeholders so that the recommendations of ETSI TS 101 470 [i.2] and ETSI TR 103 170 [i.3] can be implemented. It
can also be used to assess if Total Conversation requirements are fulfilled by other necessary standards, and to ensure
that there are no contradictions.

ETSI
8 ETSI TR 103 201 V1.1.1 (2016-03)
1 Scope
The present document:
• Assesses the support of Total Conversation for emergency communications by existing specifications, in
particular those from 3GPP and IETF.
• Identifies any changes that might be needed to those specifications to support Total Conversation for
emergency communications.
• Provides guidance for developers and PSAPs planning to implement Total Conversation for emergency
communications, and for users of the Total Conversation service.
The present document covers emergency calls with the full media set of Total Conversation as well as subsets of the
media, except voice calls in which no assisting service is needed.
Although the focus of the present document is Total Conversation for emergency communications, no Total
Conversation user can be expected to use Total Conversation only for contacting emergency services. Therefore and
where applicable, some aspects of use of Total Conversation for non-emergency communications are also covered.
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://docbox.etsi.org/Reference/.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
Not applicable.
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] EENA NG1-1-2 Long Term Definition.
[i.2] ETSI TS 101 470: "Emergency Communications (EMTEL); Total Conversation Access to
Emergency Services".
[i.3] ETSI TR 103 170: "Emergency Communications (EMTEL); Total Conversation Access to
Emergency Services".
[i.4] ETSI TR 102 180: "Emergency Communications (EMTEL); Basis of requirements for
communication of individuals with authorities/organizations in case of distress (emergency call
handling)".
ETSI
9 ETSI TR 103 201 V1.1.1 (2016-03)
[i.5] ETSI ES 202 975: "Human Factors (HF); Requirements for relay services".
[i.6] ETSI TS 122 173: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); LTE; IP Multimedia Core Network Subsystem (IMS)
Multimedia Telephony Service and supplementary services; Stage 1 (3GPP TS 22.173)".
[i.7] ETSI TS 126 114: "Universal Mobile Telecommunications System (UMTS); LTE; IP Multimedia
Subsystem (IMS); Multimedia telephony; Media handling and interaction (3GPP TS 26.114)".
[i.8] ETSI TS 123 167:"Universal Mobile Telecommunications System (UMTS); LTE; IP Multimedia
Subsystem (IMS) emergency sessions (3GPP TS 23.167)".
[i.9] ETSI TS 122 101: "Universal Mobile Telecommunications System (UMTS); LTE; Service
aspects; Service principles (3GPP TS 22.101)".
[i.10] ETSI TS 122 228: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); LTE; Service requirements for the Internet Protocol (IP)
multimedia core network subsystem (IMS); Stage 1 (3GPP TS 22.228)".
[i.11] IETF RFC 6881: "Best Current Practice for Communications Services in Support of Emergency
Calling (BCP 181)".
[i.12] IETF RFC 4596: "Guidelines for Usage of the Session Initiation Protocol (SIP) Caller Preferences
Extension".
[i.13] IETF RFC 3841: "Caller Preferences for the Session Initiation Protocol (SIP)".
[i.14] IETF RFC 6443: "Framework for Emergency Calling Using Internet Multimedia".
[i.15] IETF RFC 4190: "Framework for Supporting Emergency Telecommunications Service (ETS) in
IP Telephony".
[i.16] IETF RFC 3261: "Session Initiation Protocol".
[i.17] Recommendation ITU-T F.742: "Service description and requirements for videotelephony services
over IP networks".
[i.18] Recommendation ITU-T F.703: "Multimedia Conversational Services".
[i.19] Recommendation ITU-T V.18: "Operational and interworking requirements for DCEs operating in
the text telephone mode".
[i.20] ETSI TS 122 071: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); LTE; Services (LCS); Service description (3GPP
TS 22.071)".
[i.21] ETSI TS 123 271: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); LTE; Functional stage 2 description of Location Services
(LCS) (3GPP TS 23.271)".
[i.22] ETSI TS 124 229: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); LTE; IP multimedia call control protocol based on Session
Initiation Protocol (SIP) and Session Description Protocol (SDP) (3GPP TS 24.229)".
[i.23] IETF RFC 4353: "A Framework for Conferencing with the Session Initiation Protocol (SIP)".
[i.24] Directive 2002/22/EC of the European Parliament and the Council of 7 March 2002 on universal
service and users' rights relating to electronic communications networks and services (Universal
Service Directive).
[i.25] ETSI TS 133 106: "Universal Mobile Telecommunications System (UMTS); LTE; 3G security;
Lawful interception requirements (3GPP TS 33.106)".
[i.26] ETSI ES 201 158 (V1.2.1): "Telecommunications security; Lawful Interception (LI);
Requirements for network functions".
ETSI
10 ETSI TR 103 201 V1.1.1 (2016-03)
[i.27] ETSI TS 123 237: "Digital cellular telecommunications system (Phase 2+);Universal Mobile
Telecommunications System (UMTS); LTE; IP Multimedia Subsystem (IMS) Service Continuity;
Stage 2 (3GPP TS 23.237)".
[i.28] IETF RFC 5631: "Session Initiation Protocol (SIP) Session Mobility".
[i.29] IETF RFC 5589: "Session Initiation Protocol (SIP) Call Control ‐ Transfer".
[i.30] IETF RFC 4579: "Session Initiation Protocol (SIP) Call Control - Conferencing for User Agents".
[i.31] IETF RFC 3515: "The Session Initiation Protocol (SIP) Refer Method".
[i.32] IETF RFC 3725: "Best Current Practices for Third Party Call Control (3pcc) in the Session
Initiation Protocol (SIP)".
[i.33] IETF RFC 5646: "Tags for Identifying Languages".
[i.34] ETSI TS 122 226: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); LTE; Global text telephony (GTT); Stage 1
(3GPP TS 22.226)".
[i.35] ETSI TS 123 226: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS);
...