SIST-TS CEN/TS 17184:2023

Intelligent transport systems - eSafety - eCall High level application protocols (HLAP) using IP Multimedia Subsystem (IMS) over packet switched networks

In respect of pan European eCall (operating requirements defined in EN 16072), this document defines the high level application protocols, procedures and processes required to provide the eCall service via a packet switched wireless communications network using IMS (IP Multimedia Subsystem) and wireless access (such as LTE, NR and their successors).
This document assumes support of eCall using IMS over packet switched networks by an IVS and a PSAP and further assumes that all PLMNs available to an IVS at the time an eCall or test eCall is initiated are packet switched networks. Support of eCall where eCall using IMS over packet switched networks is not supported by an IVS or PSAP is out of the scope of this document.
At some moment in time packet switched networks will be the only Public Land Mobile Networks (PLMN) available. However as long as GSM/UMTS PLMNs are available (Teleservice 12/TS12) ETSI TS 122 003 will remain operational. Both the use of such PLMNs and the logic behind choosing the appropriate network in a hybrid situation (where both packet-switched and circuit-switched networks are available) are out of scope of this document.
NOTE 1   The objective of implementing the pan-European in-vehicle emergency call system (eCall) is to automate the notification of a traffic accident, wherever in Europe, with the same technical standards and the same quality of services objectives by using a PLMN (such as ETSI prime medium) which supports the European harmonized 112/E112 emergency number (TS12 ETSI TS 122 003 or IMS packet switched network) and to provide a means of manually triggering the notification of an emergency incident.
NOTE 2   HLAP requirements for third party services supporting eCall can be found in EN 16102,. This document makes reference to those provisions but does not duplicate them.

Intelligente Verkehrssysteme - eSicherheit - Allgemeines eCall Anwendungsprotokoll (HLAP) unter Verwendung von IMS paketvermittelnden Netzwerken

Bezüglich des gesamteuropäischen eCalls (Betriebsanforderungen nach EN 16072), legt dieses Dokument die übergeordneten Anwendungsprotokolle, Verfahren und Prozesse fest, die zur Bereitstellung des eCall Dienstes über ein paketvermitteltes Mobilfunk-Kommunikationsnetzwerk mit IMS (IP Multimedia Subsystem) und Drahtloszugang über LTE, NR und deren Nachfolger erforderlich sind.
In diesem Dokument wird davon ausgegangen, dass eCall mit IMS über paketvermittelte Netzwerke von einem IVS und einem PSAP unterstützt wird und dass alle PLMN, die einem IVS zum Zeitpunkt der Einleitung eines eCalls oder Prüf-eCalls zur Verfügung stehen, paketvermittelte Netzwerke sind. Die Unterstützung von eCall in Fällen, in denen eCall mit IMS über paketvermittelte Netzwerke von einem IVS oder PSAP nicht unterstützt wird, liegt außerhalb des Anwendungsbereichs dieses Dokuments.
Irgendwann werden paketvermittelte Netzwerke die einzigen verfügbaren öffentlichen Mobilfunknetze (PLMN, en: Public Land Mobile Networks) sein. Solange jedoch GSM/UMTS-PLMNs verfügbar sind (Teleservice 12/TS12), wird ETSI TS 122 003 in Betrieb bleiben. Sowohl die Nutzung solcher PLMNs als auch die Logik hinter der Auswahl des geeigneten Netzes in einer hybriden Situation (in der sowohl paketvermittelte als auch leitungsvermittelte Netzwerke verfügbar sind) sind nicht Gegenstand dieses Dokuments.
ANMERKUNG 1   Das Ziel der Implementierung eines gesamteuropäischen, bordeigenen Notrufsystems (eCall) ist, die Meldung eines Verkehrsunfalls an einem beliebigen Ort in Europa mit denselben technischen Standards und derselben Qualität der Dienst-Zielvorgaben, indem PLMN (z. B. als primäres ETSI-Medium) genutzt wird, das die vereinheitlichte Europäische Notrufnummer 112/E112 (TS12 ETSI TS 122 003 oder IMS-paketvermitteltes Netzwerk) unterstützt, und um ein Mittel zur manuellen Auslösung einer Notfallmeldung bereitzustellen.
ANMERKUNG 2   HLAP-Anforderungen für Dienste von Drittanbietern, die eCall unterstützen, sind in EN 16102 zu finden. Dieses Dokument bezieht sich auf diese Bestimmungen, aber sie dupliziert sie nicht.

Systèmes de transport intelligents - ESafety - Exigences de protocole d'application de haut niveau (HLAP) relatives à l'eCall via des systèmes IMS basés sur la commutation de paquets

Inteligentni transportni sistemi - e-Varnost - Visokonivojski aplikacijski protokoli za e-Klic (HLAP) z uporabo IP multimedijskega podsistema (IMS) v paketno preklopnih omrežjih

V zvezi z zagotavljanjem vseevropske storitve e-Klic (operativne zahteve so opredeljene v standardu EN 16072) ta dokument opredeljuje visokonivojske aplikacije, postopke in procese, ki so potrebni za zagotavljanje vseevropske storitve e-Klic prek paketno preklopnih brezžičnih komunikacijskih omrežij z uporabo IMS (multimedijski sistem internetnega protokola) in brezžičnega dostopa (kot so LTE, NR in njuni nasledniki).
Ta dokument predpostavlja podporo vseevropski storitvi e-Klic z uporabo multimedijskega sistema internetnega protokola) prek paketno preklopnih omrežij, ki jih zagotavljajo sistem v vozilu in center za usklajevanje reševanja, in nadalje predpostavlja, da so vsa javna kopenska mobilna omrežja na voljo sistemu v vozilu v času storitve e-Klic ali pri preskusni storitvi e-Klic paketno preklopna omrežja. Podpora storitvi e-Klic z uporabo multimedijskega sistema internetnega protokola prek paketno preklopnih omrežij, ki je ne zagotavljajo sistemi v vozilu ali centri za usklajevanje reševanje, ni zajeta v ta dokument.
V določenem času bodo paketno preklopna omrežja edina razpoložljiva javna kopenska mobilna omrežja. Dokler pa bodo na voljo javna kopenska mobilna omrežja prek povezave GMS/UMTS (telefonska storitev 12/TS12), bo veljal standard ETSI TS 122 003. Ta dokument ne obravnava uporabe tovrstnih javnih mobilnih kopenskih omrežij in logike za izbiro ustreznega omrežja v hibridnih situaciji (ko sta na voljo paketno preklopno in vodovno komutirano omrežje).
OPOMBA 1:   Cilj uvedbe vseevropskega sistema za klic v sili v vozilih (elektronski klic v sili) je avtomatizirati obveščanje ob prometni nesreči, kjer koli v Evropi, z enakimi tehničnimi standardi in enakimi cilji glede kakovosti storitev z uporabo »javnih kopenskih mobilnih omrežij« (PLMN) (kot je primarni medij ETSI), ki podpirajo evropsko usklajeno številko za nujne primere 112/E112 (TS12 ETSI/TS 122 003 ali paketno komutirano omrežje (IMS), ter zagotoviti način za ročno pošiljanje obvestila ob prometni nesreči.
OPOMBA 2:   Zahteve za visoko stopnjo prednosti aplikacijskega protokola (HLAP) za storitve tretjih strani v podporo elektronskemu klicu v sili so navedene v standardu EN 16102. Ta dokument se sklicuje na te določbe, a jih ne podvaja.

General Information

• Status: Withdrawn
• Publication Date: 06-Apr-2023
• Withdrawal Date: 06-Jan-2025
• ICS: 03.220.01 - Transport in general
• ICS: 35.240.60 - IT applications in transport
• Technical Committee: ITC - Information technology
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 24-Dec-2024
• Due Date: 16-Jan-2025
• Completion Date: 07-Jan-2025
• Directive: 2010/40/EU - Directive 2010/40/EU of the European Parliament and of the Council of 7 July 2010 on the framework for the deployment of Intelligent Transport Systems in the field of road transport and for interfaces with other modes of transport Text with EEA relevance
• Mandate: M/546 - [C(2016)808 Urban ITS (Intelligent Transport Systems in the field of road transport and for interfaces with other modes of transport)
• Ref Project: CEN/TS 17184:2022 - Intelligent transport systems - eSafety - eCall High level application protocols (HLAP) using IP Multimedia Subsystem (IMS) over packet switched networks

Relations

• Replaces: SIST-TS CEN/TS 17184:2018 - Intelligent transport systems - eSafety - eCall High level application Protocols (HLAP) using IMS packet switched networks
• Effective Date: 01-May-2023
• Replaced By: SIST EN 17184:2025 - Intelligent transport systems - eSafety - eCall High level application protocols (HLAP) using IP Multimedia Subsystem (IMS) over packet switched networks
• Effective Date: 01-Feb-2025

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2023
Nadomešča:
SIST-TS CEN/TS 17184:2018
Inteligentni transportni sistemi - e-Varnost - Visokonivojski aplikacijski protokoli
za e-Klic (HLAP) z uporabo IP multimedijskega podsistema (IMS) v paketno
preklopnih omrežjih
Intelligent transport systems - eSafety - eCall High level application protocols (HLAP)
using IP Multimedia Subsystem (IMS) over packet switched networks
Intelligente Verkehrssysteme - eSicherheit - Allgemeines eCall Anwendungsprotokoll
(HLAP) unter Verwendung von IMS paketvermittelnden Netzwerken
Systèmes de transport intelligents - ESafety - Exigences de protocole d'application de
haut niveau (HLAP) relatives à l'eCall via des systèmes IMS basés sur la commutation
de paquets
Ta slovenski standard je istoveten z: CEN/TS 17184:2022
ICS:
03.220.01 Transport na splošno Transport in general
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 17184
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
December 2022
TECHNISCHE SPEZIFIKATION
ICS 35.240.60 Supersedes CEN/TS 17184:2018
English Version
Intelligent transport systems - eSafety - eCall High level
application protocols (HLAP) using IP Multimedia
Subsystem (IMS) over packet switched networks
Systèmes de transport intelligents - ESafety - Exigences Intelligente Verkehrssysteme - eSicherheit -
de protocole d'application de haut niveau (HLAP) Allgemeines eCall Anwendungsprotokoll (HLAP) unter
relatives à l'eCall via des systèmes IMS basés sur la Verwendung von IMS paketvermittelnden Netzwerken
commutation de paquets
This Technical Specification (CEN/TS) was approved by CEN on 30 October 2022 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17184:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 8
4 Symbols and abbreviations . 12
5 Conformance . 13
6 General overview of pan European eCall session via Packet Switched networks . 13
6.1 General principle . 13
6.2 eCall over Packet Switched networks . 14
6.3 eCall using IMS over Packet Switched networks . 14
6.4 The hybrid situation . 19
7 Requirements . 20
7.1 General requirements . 20
7.1.1 General . 20
7.1.2 Enabled IVS. 20
7.1.3 Enabled PSAP . 20
7.1.4 eCall only IVS . 20
7.2 Procedures following power-up of the in-vehicle system . 21
7.2.1 Self-test . 21
7.2.2 Standby mode applicable to eCall only IVS . 21
7.3 Activation . 21
7.3.1 Activation of eCall using IMS over packet switched networks . 21
7.3.2 Activation of a test eCall . 22
7.4 Call set-up . 22
7.4.1 General . 22
7.4.2 eCall in progress . 22
7.4.3 Network selection and registration . 23
7.4.4 Authentication of the subscriber . 23
7.4.5 Establishment of an eCall using IMS over packet switched networks . 23
7.4.6 Cell localization (by network) . 24
7.4.7 Manual termination of eCall by vehicle occupants before trigger confirmation . 24
7.4.8 Call failure . 24
7.4.9 Security . 24
7.5 MSD transfer for eCall using IMS over packet switched networks . 24
7.6 Application layer acknowledgement (AL-ACK) . 25
7.6.1 General . 25
7.6.2 Successful receipt by the PSAP of the initial MSD . 26
7.6.3 Unsuccessful receipt by the PSAP of initial MSD . 26
7.6.4 No receipt of acknowledgement . 26
7.6.5 Other forms of acknowledgement . 27
7.7 PSAP requests a new MSD . 27
7.7.1 General . 27
7.7.2 Before session clear-down . 27
7.7.3 After session clear-down . 28
7.8 MSD transfer using in-band modem (optional) . 28
7.9 Audio link to vehicle occupants . 28
7.10 eCall clear-down . 28
7.11 PSAP call back . 29
7.12 Rerouting to another PSAP/emergency control centre . 29
7.13 Handling non equipped situations / error cases . 30
7.13.1 Network related issues . 30
7.13.2 MSD related issues . 30
7.13.3 PSAP network/ICT failure . 31
7.13.4 Call related issues . 32
8 Third party services supported eCall (TPS-eCall) . 32
9 Defences against attack (Security provisions) . 33
10 Quality of service requirements . 33
11 Test and conformance requirements . 33
12 Marking, labelling and packaging . 33
13 Declaration of patents and intellectual property . 33
Annex A (normative) Table of timings . 34
Annex B (informative) SIP and IMS explained. 36
Bibliography . 50

European foreword
This document (CEN/TS 17184:2022) has been prepared by Technical Committee CEN/TC 278
“Intelligent transport systems”, the secretariat of which is held by NEN.
This document supersedes CEN/TS 17184:2018.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
Part of this revision of the document is aimed at making it purely packet switched and removing
references to eCall over circuit switched networks, this in order to make the document future proof.
In comparison with the previous edition, the following technical modifications have been made:
— reordering and combining of some clauses to better reflect coherence and provide consistency
(numbering below refers to the current numbering; where this differs from the numbering in the
previous published version of this document, the original number is cited stroke through and
between brackets)
— provide a mechanism to transfer the MSD via in-band modem via IMS as an option (Clause 7.8 (7.3.6
and 7.4.3))
— added expected IVS behaviour after reception of 6xx or 4xx response including positive MSD ACK
(updated Clauses 7.4.1, 7.6.2 and 7.13.3 (7.3.6 and 7.14.4))
— removed section about PSAP application (7.8) which was moved to EN 16072
— updated expected IVS behaviour when the PSAP operator does not respond (updated
Clauses 7.13.3.2 and 7.13.3.3 (7.14.3 and 7.14.4))
— updated definition of test eCall activation (updated Clauses 7.3.2 and 7.4.5 (7.2.2 and 7.3.6))
— updated Clauses 7.5, 7.13.1, 7.13.4.1 (7.4.2, 7.4.3, 7.5.2, 7.13.3, 7.13.4.2) and Annex B
— updated terms, definitions, symbols and abbreviations
— removed requirement to fall-back to CS eCall
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Introduction
An eCall is an emergency call generated either automatically via activation of in-vehicle sensors or
manually by the vehicle occupants; when activated, to provide notification and relevant location
information to the most appropriate Public Safety Answering Point (PSAP), by means of mobile wireless
communications networks and carries a defined standardized minimum set of data, notifying that there
has been an incident that requires response from the emergency services and establishes an audio
channel between the occupants of the vehicle and the most appropriate PSAP.
EN 15722 specifies a standardized MSD for eCall, and EN 16072 specifies pan-European eCall operating
requirements (for third party systems, EN 16102 specifies third party services supporting eCall operating
requirements; see EC Communication on eCall Implementation 2009 [COM(2009) 434 final] and Official
Journal eCall Recommendation C_2011_6269, for more information) and EN 16062 specifies High Level
Application Protocols for eCall using GSM/UMTS.
The operating requirements for pan-European eCall are made using Public Land Mobile Networks
(PLMN) (such as GSM and UMTS, and latterly LTE, NR and their successors), as specified in a number of
ETSI standards and technical specifications.
In order to provide the eCall service across a wireless network, high level application protocols are
required as an important essential element to affect this service provision.
NOTE The term PSAP, which is most widely used in the eCall documentation, European Commission
documents, etc., is used throughout this document and equates to the term emergency call response centre used in
the ITS Implementation Directive.
Subsequent to the publication of the suite of eCall standards (EN 16072, EN 16062 and EN 16454) which
support the eCall Regulations, new communications technologies have become available. Over the course
of time, these networks (such as LTE, NR and their successors) are expected to complement and
eventually replace the circuit switched GSM/UMTS networks. These technologies use so called ‘packet
switched’ technologies using Internet protocols (IP). Particularly, 3GPP have evolved a communication
management system called IMS (IP Multimedia Subsystem) which is suitable to operate over a number
of bearer technologies, including LTE, NR and their successors.
In circuit switched networks the eCall is identified as an emergency call and specifically an eCall in the
telecircuit switching (TS) process. No number is dialled as the TS identifiers inform the MNO that the call
is an emergency call/eCall and the MNO has procedures to direct these calls to “the most appropriate”
PSAP. Having established a voice channel, the microphones and speakers are muted and a modem is used
to transfer the Minimum Set of Data (MSD) to the PSAP before opening up the line to enable conversation
between the PSAP operator and the occupants of the vehicle.
In a ‘packet switched’ network, packets of data (including voice) are sent using an internet protocol (IP)
communication system. 3GPP have created the IP Multimedia Subsystem (IMS) which makes use of SIP
(Session Initiation Protocol) for its call management.
This document provides High Level Application Protocols (HLAP) for eCall using IMS. It therefore
provides the IMS packet switched equivalent of EN 16062 for circuit switched networks and should be
suitable for all/any packet switched networks that support IMS and wireless access such as LTE, NR and
their successors.
This document specifies the protocols to put into effect the pan-European eCall operating requirements,
over packet switched networks networks (such as LTE, NR and their successors).
The European Committee for Standardization (CEN) draws attention to the fact that, while no direct
patents are known in express regard to the content of these specifications, the underlying ETSI
communications Standards may involve patents and the reader is directed to the referenced ETSI
standards in these respects.
1 Scope
In respect of pan European eCall (operating requirements defined in EN 16072), this document defines
the high level application protocols, procedures and processes required to provide the eCall service via a
packet switched wireless communications network using IMS (IP Multimedia Subsystem) and wireless
access (such as LTE, NR and their successors).
This document assumes support of eCall using IMS over packet switched networks by an IVS and a PSAP
and further assumes that all PLMNs available to an IVS at the time an eCall or test eCall is initiated are
packet switched networks. Support of eCall where eCall using IMS over packet switched networks is not
supported by an IVS or PSAP is out of the scope of this document.
At some moment in time packet switched networks will be the only Public Land Mobile Networks (PLMN)
available. However as long as GSM/UMTS PLMNs are available (Teleservice 12/TS12) ETSI TS 122 003
will remain operational. Both the use of such PLMNs and the logic behind choosing the appropriate
network in a hybrid situation (where both packet-switched and circuit-switched networks are available)
are out of scope of this document.
NOTE 1 The objective of implementing the pan-European in-vehicle emergency call system (eCall) is to automate
the notification of a traffic accident, wherever in Europe, with the same technical standards and the same quality of
services objectives by using a PLMN (such as ETSI prime medium) which supports the European harmonized
112/E112 emergency number (TS12 ETSI TS 122 003 or IMS packet switched network) and to provide a means of
manually triggering the notification of an emergency incident.
NOTE 2 HLAP requirements for third party services supporting eCall can be found in EN 16102,. This document
makes reference to those provisions but does not duplicate them.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 15722, Intelligent transport systems - ESafety - ECall minimum set of data
EN 16072:2022, Intelligent transport systems - ESafety - Pan-European eCall operating requirements
EN 16454, Intelligent transport systems - ESafety - ECall end to end conformance testing
CEN/TS 17240, Intelligent transport systems - ESafety - ECall end to end conformance testing for IMS packet
switched based systems
ETSI TS 122 003, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; Circuit Teleservices supported by a Public Land Mobile Network
(PLMN) (3GPP TS 22.003) [Release 14 or later]
ETSI TS 122 011, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; Service accessibility (3GPP TS 22.011) [Release 14 or later]
ETSI TS 122 071, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; Location Services (LCS); Service description; Stage 1
(3GPP TS 22.071 [Release 14 or later]
ETSI TS 122 101, Universal Mobile Telecommunications System (UMTS); LTE; Service aspects; Service
principles (3GPP TS 22.101) [Release 14 or later]
ETSI TS 123 122, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; Non-Access-Stratum (NAS) functions related to Mobile Station
(MS) in idle mode (3GPP TS 23.122) [Release 14 or later]
ETSI TS 123 167, Universal Mobile Telecommunications System (UMTS); LTE; IP Multimedia Subsystem
(IMS) emergency sessions (3GPP TS 23.167) [Release 14 or later]
ETSI TS 123 216, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; Single Radio Voice Call Continuity (SRVCC); Stage 2
(3GPP TS 23.216) [Release 14 or later]
ETSI TS 123 401, LTE; General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial
Radio Access Network (E-UTRAN) access (3GPP TS 23.401) [Release 14 or later]
ETSI TS 123 501, 5G; System architecture for the 5G System (5GS) (3GPP TS 23.501) [Release 14 or later]
ETSI TS 124 229, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; IP multimedia call control protocol based on Session Initiation
Protocol (SIP) and Session Description Protocol (SDP); Stage 3 (3GPP TS 24.229) [Release 14 or later]
ETSI TS 124 301, Universal Mobile Telecommunications System (UMTS); LTE; Non-Access-Stratum (NAS)
protocol for Evolved Packet System (EPS); Stage 3 (3GPP TS 24.301) [Release 14 or later]
ETSI TS 124 501, 5G; Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3 (3GPP TS 24.501)
[Release 14 or later]
ETSI TS 131 102, Universal Mobile Telecommunications System (UMTS); LTE; Characteristics of the
Universal Subscriber Identity Module (USIM) application (3GPP TS 31.102) [Release 14 or later]
ETSI TS 133 203, Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile
Telecommunications System (UMTS); LTE; 3G security; Access security for IP-based services
(3GPP TS 33.203) [Release 14 or later]
ETSI TS 136 331, LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC);
Protocol specification (3GPP TS 36.331) [Release 14 or later]
ETSI TS 138 331, 5G; NR; Radio Resource Control (RRC); Protocol specification (3GPP TS 38.331) [Release
15 or later]
IETF RFC 8147, Next-Generation Pan-European eCall
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
single European emergency call number supporting Teleservice 12
Note 1 to entry: See ETSI TS 122 003.
3.2
call clear-down
termination of call and freeing up of line (usually achieved by hanging up the receiver or pressing ‘end
call’ or similar on screen)
3.3
cellular network
wireless communications network consisting of multiple adjacent access points (cells) with the capability
of homogeneous transfer of a communications session instance to an adjacent cell without significant
interruption to the session
3.4
data
representations of static or dynamic objects in a formalized manner suitable for communication,
interpretation, or processing by humans or by machines; in packet switched networks, voice is carried in
packets of data
3.5
data concept
any of a group of data structures (i.e. object class, property, value domain, data elements, message,
interface dialogue, association) referring to abstractions or things in the natural world that can be
identified with explicit boundaries and meaning and whose properties and behaviour all follow the same
rules
3.6
data element
single unit of information of interest (such as a fact, proposition, observation, etc.) about some (entity)
class of interest (e.g. a person, place, process, property, concept, state, event) considered to be indivisible
in a particular context
3.7
eCall
emergency call generated either automatically via activation of in-vehicle sensors or manually by the
vehicle occupants
Note 1 to entry: When activated it provides notification and relevant location information to the most appropriate
Public Safety Answering Point, by means of mobile wireless communications networks, carries a defined standardized
minimum set of data (MSD) notifying that there has been an incident that requires response from the emergency
services, and establishes an audio channel between the occupants of the vehicle and the most appropriate Public
Safety Answering Point.
3.8
eCall generator
occupant of a vehicle or equipment within a vehicle that has cause to trigger an eCall session by automatic
or manual means
3.9
eCall service
end-to-end emergency service to connect occupants of an affected vehicle to the most appropriate PSAP
via an audio link across a PLMN together with the transfer of a minimum set of data to the PSAP
3.10
eCall session
establishment of a mobile wireless communications session across a public wireless communications
network and the transmission of a minimum set of data from a vehicle to a public safety answering point
and the establishment of an audio channel between the vehicle and the PSAP
3.11
Emergency Call Server
ECS
functional entity that consists of a Location Retrieval Function (LRF) and either a routing proxy or a
redirect server, e.g. an ECS contains a VPC and a Routing Proxy or Redirect Server in NENA I2 architecture
3.12
emergency control centre
unit which deals with emergency calls and which has the capacity to consider professionally the need for
response, and which has the provision to mobilise the needed resources to deal with the emergency in
question
3.13
emergency call response centre
term used in ITS Implementation Directive to mean Public Safety Answering Point (PSAP)
3.14
identifier
label, symbol or token that names or identifies an entity or a collection of data or the means of designating
or referring to a specific instance of a data concept
3.15
in-vehicle equipment
equipment within the vehicle that provides or has access to in-vehicle data required for the minimum set
of data and any other data that is to be sent as part of or complementary to the minimum set of data to
effect the eCall session via a public mobile wireless communications network providing a link between
the vehicle and a means of enacting the eCall service via a public mobile wireless communications
network
3.16
in-vehicle equipment provider
provider of eCall in-vehicle equipment
Note 1 to entry: The in-vehicle equipment provider can be the vehicle manufacturer or the provider of aftermarket
equipment.
3.17
in-vehicle system
IVS
in-vehicle equipment together with the means to trigger, manage and effect the eCall session
3.18
location area
LA
area in which a mobile station may move freely without updating the VLR
Note 1 to entry: A location area includes one or several GERAN/UTRAN cells.
3.19
minimum set of data
MSD
standardized data concept comprising data elements of relevant vehicle generated data essential for the
performance of the eCall service
Note 1 to entry: See EN 15722.
3.20
mobile wireless communications network
wireless communications network with homogeneous handover between network access points
3.21
most appropriate PSAP
destination for eCall defined beforehand by responsible authorities to cover emergency calls from a
certain area or for emergency calls of a certain type
Note 1 to entry: See also PSAP.
Note 2 to entry: A number of different instantiations of PSAP service are supported within this document. A PSAP
can be a Public Authority or a private service provider operating on behalf of the responsible authorities.
3.22
network access device
NAD
device providing communications to a mobile wireless communications network with homogeneous
handover between network access points, also known as mobile wireless communications network device
3.23
network access point
beacon, antenna or similar source of signal propagation and receipt together with equipment to manage
communication sessions with users operating within the operating reach of the network access point and
provide connectivity for the users within the operating reach of the single access point to a wider
communications network
Note 1 to entry: A network access point may but does not need to provide homogeneous or heterogeneous
handover to another network access point.
3.24
public mobile wireless communications network
mobile wireless communications network with access to a public telecommunications network
3.25
Public Safety Answering Point
PSAP
physical location working on behalf of the national authorities where emergency calls are first received
under the responsibility of a public authority or a private organization recognized by the national
government
Note 1 to entry: See also most appropriate PSAP.
Note 2 to entry: A number of different instantiations of PSAP service are supported within this document.
3.26
Radio Network Controller area
RNC area
area of radio coverage consisting of one or more cells controlled by one RNC
Note 1 to entry: The boundaries of an RNC area and a location area are independent; a location area may span the
boundary between RNC area and an RNC area may span the boundary between location areas.
3.27
routing area
RA
area in which a mobile station, in certain operation modes, may move freely without updating the SGSN
Note 1 to entry: A routing area includes one or several GERAN/UTRAN cells and is always contained within a
location area.
3.28
vehicle manufacturer
entity which first assembles the vehicle and provides eCall equipment as part of its specification and
subsequently sells the vehicle directly or via an agent
3.29
vehicle occupant
person inside the vehicle
3.30
wireless communications network
network operating using an air-interface capable of bi-directional transfer of data and or voice
Note 1 to entry: There are different types of wireless communications such as PAN, LAN, cellular network, etc.
4 Symbols and abbreviations
3G 3rd Generation
3GPP Third Generation Partnership Project
5G 5th Generation
ACK ACKnowledgement
AL-ACK Application Layer ACKnowledgement
AMF Access and mobility Management Function
CAN Controller-Area Network
CS Circuit Switched
CSCF Call Session Control Function
E-CSCF Emergency Call Session Control Function
EC European Commission
ECL eCall using IMS over packet switched networks support indicator
ESQK Emergency Service Query Key
ETSI European Telecommunications Standards Institute
GSM Global System for Mobile communications
HPLMN Home Public Land Mobile Network
HSS Home Subscriber Server
IBCF Interconnection Border Control Functions
IETF Internet Engineering Task Force
IMS IP Multimedia Subsystem
IMSI International Mobile Subscriber Identity
IP-CAN IP- Connectivity Access Network
IVS In-Vehicle System
LAN Local Area Network
LL-ACK Lower Layer ACKnowledgement
LRF Location Retrieval Function
LTE Long Term Evolution
MME Mobility Management Entity
MNO Mobile Network Operator
MSD Minimum Set of Data
NAD Network Access Device
NENA National Emergency Numbering Association
NG-RAN Next Generation Radio Access Network
NR New Radio
P-CSCF Proxy Call Session Control Function
PAN Personal Area Network
PCRF Policy and Charging Rules Function
PLMN Public Land Mobile Network
PS Packet Switched
PSAP Public Safety Answering Point
RDF Routing Determination Function
REQ REQuest
RNC Radio Network Controller
TEL-URI Telephone Uniform Resource Identifier
S-CSCF Serving Call State Control Function
SDP Session Description Protocol
SIP Session Initiation Protocol
TPS Third Party Service
TPSP Third Party Service Provider
TS (i) Technical Specification
TS (ii) Teleservice
TS12 Teleservice 12
UE User Equipment
NOTE: ETSI/3GPP term which general refers to the IVS in the context of eCall
UMTS Universal Mobile Telecommunication System
USIM Universal Subscriber Identity Module
VoIP Voice over IP
VLR Visited Location Register
VPC VoIP Positioning Centre
WGS-84 World Geodetic System 1984
5 Conformance
Conformance to the requirements of this document for eCall using IMS over packet switched networks
are to be found in CEN/TS 17240.
This document makes no conformance specifications or requirements in respect of TPS eCall operating
requirements, and conformance requirements in respect of TPS eCall can be found in EN 16102.
6 General overview of pan European eCall session via Packet Switched networks
6.1 General principle
In the introduction to the document, EN 16072, eCall was described as an emergency call generated either
automatically via activation of in-vehicle sensors or manually by the vehicle occupants (the eCall
generator); when activated, it provides notification and relevant location information to the most
appropriate Public Safety Answering Point, by means of mobile wireless communications networks and
carries a defined standardized minimum set of data, notifying that there has been an incident that requires
response from the emergency services and establishes an audio channel between the occupants of the
vehicle and the most appropriate Public Safety Answering Point.
Figure 1 shows an illustrative view of the pan-European eCall service, as defined in EN 16072.

Figure 1 — General overview: pan European eCall service using GSM/UMTS
In circuit switched networks the eCall is identified as an emergency call and specifically an eCall in the
telecircuit switching (TS) process. The emergency number (112) is not dialled as the TS identifiers inform
the MNO that the call is an emergency call/eCall and the MNO has procedures to direct these calls to “the
most appropriate” PSAP. Having established a voice channel, the microphones and speakers are muted
and a modem is used to transfer the Minimum Set of Data (MSD) to the PSAP before opening up the line
to enable conversation between the PSAP operator and the occupants of the vehicle.
6.2 eCall over Packet Switched networks
Technology advances and subsequently to the development of the eCall application suite EN 16072,
EN 16062 and EN 16454 standards, packet switched networks have become available. Over the course of
time, these packet switched networks (such as LTE, NR and their successors) are expected to provide
new PLMNs to complement and eventually replace the circuit switched GSM/UMTS networks.
The high level paradigm for eCall remains unchanged, but there are fundamental differences in packet
switched networks: the TS mechanism is not available and the switching paradigm is different, allowing
for a more robust way of data transfer. 3GPP has developed IMS (IP Multimedia Subsystem) which is an
all-IP (Internet Protocol) system designed to assist mobile operators deliver next generation interactive
and interoperable services, cost-effectively, over an architecture providing the flexibility of the Internet.
IMS is designed for packet switched networks and supports IP multimedia applications via IP multimedia
sessions over a multitude of IP Connectivity Access Networks, such as NG-RAN, E-UTRAN, UTRAN,
GERAN, LAN, DOCSIS®, WiMAX™, cdma2000® and DVB-RCS2 access. It is likely that all subsequent
IP based packet switched networks will therefore be able to support IMS, making migration to future, as
yet undeveloped technologies, a simpler and easier to achieve process.
It is therefore appropriate to require the availability of IMS on a packet switched network for eCall to
function, rather than any of the specific wireless technologies, as it provides greater flexibility and
migration potential.
6.3 eCall using IMS over Packet Switched networks
In a packet switched environment where IMS is available, the eCall is established as an internet protocol
based session with the exchange of packets of data (which in this case, are largely packets of voice data),
and the MSD is provided as part of the session establishment. This is completely different from the mode
of operation in circuit switched networks. It is therefore necessary to provide a separate specification for
“High Level Application Protocols” to manage eCall via packet switched networks.
Figure 2 shows the IMS equivalent of Figure 1 and compares it to eCall via circuit switched networks.

Figure 2 — Overview: eCall using IMS over packet switched networks compared to eCall over CS
networks
NOTE 1 Albeit out of scope for this document, IMS has a further advantage in that it can also be used over fixed
lines. This makes the forwarding of eCalls from 1st level PSAP responder to 2nd level PSAP responders and
responding emergency services via fixed lines, an easier and more simple process; and even enabling the call to then
be subsequently diverted to a handset of a responding ambulance, fire truck or police responder.
Session Initiation Protocol (SIP) was selected as the signalling mechanism for IMS (see Annex B), thereby
allowing voice, text and multimedia services to traverse all connected networks. And is aligned with IETF
internet protocols to ensure maximum re-usability of internet standards, preventing fragmentation of
IMS standards.
Further information on this system is specified in ETSI:
— ETSI TS 122 228,
— ETSI TS 123 228,
— ETSI TS 123 167,
— ETSI TS 124 229.
(Or their 3GPP equivalent specifications)
IMS carries special and specific provision for emergency communications and these are further provided
in ETSI TS 122 101: “Service principles”, which incorporates the MSD into the SIP INVITE, and provides
priority on the network for emergency communications and IETF RFC 8147, ETSI TS 123 167 and
ETSI TS 124 229 (see also B.2 for a summary of key relevant provisions).
It is in the nature of the implementation of 3GPP specifications that the provisions that are actually
implemented/supported are left to the implementer. It is not uncommon, especially with PLMN/MNOs,
that not all provisions of a 3GPP release are supported. In order to be compliant with this European
Standard, some provisions relating to eCall from forenamed specifications are not considered mandatory
for PLMN/MNOs, IVS and PSAPs. Where appropriate this is marked in the relevant clauses.
NOTE 2 The provisions referenced as optional are so specified because those are possibly not practicably
supportable by many PSAP organization deployments, and in some of these implementations could cause other
technical issues, and could only be used compliant to the additional provisions elaborated in this document.
With IMS, there is no requirement for eCall for potentially complicated muting and reconnecting
loudspeakers and microphones in the affected vehicle, as the MSD has already been passed on in the SIP
header. A modem is not required at either end of the eCall, although transfer by modem is an optional
requirement. eCall using IMS is therefore simpler, and has higher reliability, and potential for data in
addition to the MSD to be sent, therefore enabling “next generation” capabilities to be added to eCall,
without further changing the basic communications architecture.
Figure 3 — Relationship of eCall session to standards
NOTE 2 For lists of standards referred to in Figure 3, see Clause 2.
Whereas, in circuit switched eCall, there are acknowledgements made at both the lower communications
layer and the upper applications layer (LL-ACK and AL-ACK); using IMS, the lower layer
acknowledgements are provided automatically and invisibly by the IMS system. The MSD is sent as part
of the SIP INVITE requiring only an AL-ACK, which is sent within the SIP 200 message by the receiving
party. The AL-ACK confirms that the MSD has not only been received, but has been successfully decoded.
eCall using
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