prEN 17905

Intelligent transport systems - eSafety - eCall HLAP in hybrid circuit switched/packet switched network environments

In respect of 112-eCall (pan-European eCall) (operating requirements defined in EN 16072), this document defines the additional high level application protocols, procedures and processes required to provide the eCall service whilst there are still both circuit switched and packet switched wireless communication networks in operation.
NOTE    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.

Intelligente Verkehrssysteme - eSicherheit - Übergeordnetes eCall-Anwendungsprotokoll (HLAP) in hybriden geschalteten Netzwerkumgebungen

Hinsichtlich 112-eCalls (gesamteuropäische eCalls) (betriebliche Anforderungen in EN 16072 festgelegt), legt dieses Dokument die zusätzlichen High-Level-Anwendungsprotokolle, Verfahren und Prozesse fest, die zur Bereitstellung des eCall-Dienstes sind, solange noch sowohl leitungsvermittelte als auch paketvermittelte Mobilfunk-Kommunikationsnetzwerke in Betrieb sind.
ANMERKUNG   Das Ziel der Implementierung eines gesamteuropäischen, fahrzeuginternen Notrufsystems (eCall) ist, die Meldung eines Verkehrsunfalls an einem beliebigen Ort in Europa mit denselben technischen Standards und derselben Qualität der Dienst-Zielvorgaben zu automatisieren, indem ein öffentliches landgestütztes Mobilfunknetz (PLMN, Public Land Mobile Network) (z. B. ETSI Prime 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.

Systèmes de transport intelligents - eSafety - HLAP d’eCall dans les environnements réseaux hybrides à commutation de circuits et de paquets

Pour ce qui est du 112-eCall (eCall paneuropéen) (exigences opérationnelles définies dans l’EN 16072), le présent document définit les processus, les procédures et les protocoles d’application de haut niveau supplémentaires requis pour fournir le service eCall alors que des réseaux de communication sans fil à commutation de circuits et à commutation de paquets sont encore en service.
NOTE   La mise en oeuvre du système paneuropéen d’appel d’urgence embarqué (eCall) a pour objectif d’automatiser la notification d’un accident de la route, partout en Europe, avec les mêmes normes techniques et les mêmes objectifs de niveau de service en utilisant un RMTP (tel qu’un réseau ETSI) qui prend en charge le numéro d’urgence européen 112/E112 harmonisé (TS12 ETSI/TS 122 003 ou un réseau à commutation de paquets IMS), mais également de fournir un moyen de déclenchement manuel de notification d’un incident.

Inteligentni transportni sistemi - e-Varnost - e-Klic HLAP v hibridnih omrežnih okoljih s komutiranim vezjem/paketno komutiranim omrežjem

General Information

• Status: Not Published
• Publication Date: 25-Aug-2024
• ICS: 03.220.20 - Road transport
• ICS: 35.240.60 - IT applications in transport
• Technical Committee: CEN/TC 278 - Road transport and traffic telematics
• Drafting Committee: CEN/TC 278/WG 15 - eSafety
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Start Date: 03-May-2023
• Due Date: 23-Aug-2023
• Completion Date: 03-May-2023
• Ref Project: oSIST prEN 17905:2022 - Intelligent transport systems - eSafety - eCall HLAP in hybrid circuit switched/packet switched network environments

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 17905:2022
01-november-2022
Inteligentni transportni sistemi - e-Varnost - e-Klic HLAP v hibridnih omrežnih
okoljih s komutiranim vezjem/paketno komutiranim omrežjem

Intelligent transport systems - eSafety - eCall HLAP in hybrid circuit switched/packet

switched network environments

Intelligente Verkehrssysteme - eSicherheit - Übergeordnetes eCall-Anwendungsprotokoll

(HLAP) in hybriden geschalteten Netzwerkumgebungen

Systèmes de transport intelligents - eSafety - HLAP d’eCall dans les environnements

réseaux hybrides à commutation de circuits et de paquets
Ta slovenski standard je istoveten z: prEN 17905
ICS:
03.220.20 Cestni transport Road transport
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
oSIST prEN 17905:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 17905:2022
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oSIST prEN 17905:2022
DRAFT
EUROPEAN STANDARD
prEN 17905
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2022
ICS 03.220.20; 35.240.60
English Version
Intelligent transport systems - eSafety - eCall HLAP in
hybrid circuit switched/packet switched network
environments

Systèmes de transport intelligents - eSafety - HLAP Intelligente Verkehrssysteme - eSicherheit -

d'eCall dans les environnements réseaux hybrides à Übergeordnetes eCall-Anwendungsprotokoll (HLAP) in

commutation de circuits et de paquets hybriden geschalteten Netzwerkumgebungen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 278.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations

which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

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.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
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. prEN 17905:2022 E

worldwide for CEN national Members.
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oSIST prEN 17905:2022
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Contents Page

European foreword ............................................................................................................................................ 3

Introduction .......................................................................................................................................................... 4

1 Scope .......................................................................................................................................................... 5

2 Normative references .......................................................................................................................... 5

3 Terms and definitions ......................................................................................................................... 6

4 Symbols and abbreviations ............................................................................................................... 9

5 Conformance ........................................................................................................................................... 9

6 General overview of the eCall session for Pan European eCall ............................................ 9

7 Requirements ....................................................................................................................................... 11

7.1 General.................................................................................................................................................... 11

7.2 General requirements ....................................................................................................................... 11

7.2.1 Enabled IVS ........................................................................................................................................... 11

7.2.2 Enabled PSAP ........................................................................................................................................ 12

7.2.3 Self-test ................................................................................................................................................... 12

7.3 Activation ............................................................................................................................................... 13

7.4 Call setup (IVS) ..................................................................................................................................... 13

7.4.1 General.................................................................................................................................................... 13

7.4.2 eCall activation .................................................................................................................................... 13

7.4.3 eCall in progress .................................................................................................................................. 13

7.4.4 Domain selection ................................................................................................................................ 13

7.4.5 Fallback .................................................................................................................................................. 15

7.4.6 Domain handover ............................................................................................................................... 16

7.5 PSAP application features ................................................................................................................ 16

7.5.1 General.................................................................................................................................................... 16

7.5.2 Logging of MSD transfer type .......................................................................................................... 16

7.5.3 MSD request .......................................................................................................................................... 17

7.5.4 Information to operator about hybrid situation ..................................................................... 17

7.6 Handling non equipped situations / error cases ..................................................................... 17

7.6.1 Network registration fails ............................................................................................................... 17

7.6.2 Other issues .......................................................................................................................................... 17

8 Third party services supported eCall (TPS-eCall) ................................................................... 17

9 Defences against attack (Security provisions) ......................................................................... 17

10 Quality of service requirements .................................................................................................... 17

11 Test and conformance requirements .......................................................................................... 17

12 Marking, labelling and packaging ................................................................................................. 18

13 Declaration of patents and intellectual property .................................................................... 18

Annex A (informative) Transitional Use Cases ...................................................................................... 19

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European foreword

This document (prEN 17905:2022) has been prepared by Technical Committee CEN/TC 278 “Intelligent

transport systems”, the secretariat of which is held by NEN.
This document is currently submitted to the CEN Enquiry.

This document is the result of narrowing down the scope of CEN/TS 17184 (during the review of the TS)

to exclusively describe the eCall High Level Application Protocols in a packet switched networks and as

such partly supersedes CEN/TS 17184.
The document complements EN 16062 and CEN/TS 17184.
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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 Points (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.

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.

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).

The pan-European eCall are made using Public Land Mobile Networks (PLMN) for which operating

requirements are 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. Originally PLMN were circuit switched networks for

which EN 16062 specifies High Level Application Protocols. In these networks eCall uses Teleservice No

12 (TS12) and in-band modem transfer of data.

Over time new communications technologies have become available. 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. It is anticipated that packet

switched networks (such as LTE, NR and their successors), which now co-exist with circuit switched

networks (like GSM/UMTS), will, over the course of time, replace circuit switched networks.

CEN/TS 17184 provides High Level Application Protocols (HLAP) for eCall using IMS over packet

switched networks. It provides the equivalent of EN 16062 for circuit switched networks and should be

suitable for all/any packet switched networks and wireless access such as LTE, NR and their successors.

During at least a couple of years, packet switched networks will not be available throughout the working

area of eCall. In other areas both circuit switched and packet switched networks will co-exist, but there

will be areas that only have packet switched network services. This document specifies the protocols in

this hybrid situation, in order to make sure that pan-European eCall will function as efficiently as possible.

NOTE A (possibly) large number of vehicles support circuit switched in-band eCall only (and not eCall using

IMS over packet switched networks). For these to be able to continue using the eCall service either the onboard

equipment will need to be upgraded (to support eCall using IMS) or sufficient circuit switched networks need to

remain operational. This falls outside the scope of this document and is not addressed herein.

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. Similarly, as this standard relies on EN 16062 and CEN/TS 17184 the

specifications below may involve the use of patents specified in these standards, and the reader is

directed to these documents in respect of these aspects.
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1 Scope

In respect of 112-eCall (pan-European eCall) (operating requirements defined in EN 16072), this

document defines the additional high level application protocols, procedures and processes required to

provide the eCall service whilst there are still both circuit switched and packet switched wireless

communication networks in operation.

NOTE 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.
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 16062, Intelligent transport systems - ESafety - eCall high level application requirements (HLAP) using

GSM/UMTS circuit switched networks

EN 16072, Intelligent transport systems - ESafety - Pan-European eCall operating requirements

EN 16454, Intelligent transport systems - ESafety - ECall end to end conformance testing

CEN/TS 17184 :— , Intelligent transport systems – eSafety - eCall High level application Protocols (HLAP)

using IP Multimedia Subsystem (IMS) over packet switched networks

CEN/TS 17240, Intelligent transport systems - ESafety - ECall end to end conformance testing for IMS packet

switched based systems

CEN/TS YYYYY, Intelligent transport systems – ESafety - ECall end to end conformance testing in hybrid

switching environments

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 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 16 or later]
To be published. Stage at the time of publication: FprCEN/TS 17184:2022.
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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
112
single European emergency call number supporting Teleservice 12
Note 1 to entry: See ETSI TS 122 003.
3.2
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
3.3
CS-eCall
CS eCall
eCall over CS

emergency call generated either automatically via activation of in-vehicle sensors or manually by the

vehicle occupants via a circuit switched mobile network
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
E112

emergency communications service using the single European emergency call number, 112, which is

enhanced with location information of the calling user

Note 1 to entry: The number is not actually used directly in the communication but sets indicators in the IMS call

header that identifies the call as an emergency call of type ‘eCall’ to the MNO.
3.6
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.
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3.7
eCall generator

occupant of a vehicle or equipment within a vehicle that has cause to trigger an eCall session by automatic

or manual means
3.8
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

3.9
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
3.10
emergency call response centre

term used in ITS Implementation Directive to mean Public Safety Answering Point (PSAP)

3.11
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
3.12
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
3.13
in-vehicle system
IVS

in-vehicle equipment together with the means to trigger, manage and effect the eCall session

3.14
IMS-eCall
IMS eCall
eCall over IMS

manually or automatically initiated IMS emergency call, from an IVS, supplemented with a minimum set

of data (MSD), via a packet switched mobile network
3.15
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.
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3.16
mobile wireless communications network

wireless communications network with homogeneous handover between network access points

3.17
mobile wireless communications network device

device providing communications to a mobile wireless communications network with homogeneous

handover between network access points
3.18
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.

3.19
Network Access Device
NAD
see mobile wireless communications network device
3.20
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.

3.21
service provider

physical and functional component responsible for providing telematics based services to its subscribers

3.22
vehicle occupant
person inside the vehicle
3.23
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.

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4 Symbols and abbreviations
3G rd
3 Generation
3GPP Third Generation Partnership Project
CS Circuit Switched
EC European Commission
ECL eCall over IMS support indicator
EMS IMS Emergency Service support indicator
ETSI European Telecommunications Standards Institute
GSM Global System for Mobile communications
IMS IP Multimedia Subsystem
IVS In-Vehicle System
LAN Local Area Network
LTE Long Term Evolution
MNO Mobile Network Operator
MSD Minimum Set of Data
NAD Network Access Device
NR New Radio
PLMN Public Land Mobile Network
PS Packet Switched
PSAP Public Safety Answering Point
TPS Third Party Service
TPSP Third Party Service Provider
TS Technical Specification
TS12 Teleservice 12
UMTS Universal Mobile Telecommunication System
USIM Universal Subscriber Identity Module
VoIMS Voice over IMS
5 Conformance

Conformance requirements are to be found in CEN/TS YYYYY and subsequently in EN 16454 (for circuit

switched networks), CEN/TS 17240 (for packet switched networks).
6 General overview of the eCall session for Pan European eCall

As described in the introduction to the document, EN 16062, eCall is 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

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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: 112-eCall service using GSM/UMTS

eCall has originally been devised for so called circuit switched mobile networks, in which an eCall is

identified as an emergency call and specifically an eCall in the telecircuit switching (TS) process. 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 onboard eCall unit

then mutes microphones and speakers and uses a modem to transfer the Minimum Set of Data (MSD) to

the PSAP before unmuting the audio devices to enable conversation between the PSAP operator and the

occupants of the vehicle. This high level paradigm for circuit switched networks is described and

standardized in EN 16062 and tests for conformance are found in EN 16454.

The eCall paradigm can be extended to other means of communications and notably to packet switched

mobile networks (such as LTE, NR and their successors) that have become available providing new

PLMNs. In such networks eCall uses IMS and an eCall is established as an internet protocol based session

to a specific URN designating the call as either a manual or automatic eCall. The MSD is provided as part

of the session establishment and after it has been set up packets of data (which in this case, are largely

packets of voice data) are exchanged. The high level paradigm for packet switched networks is described

analogously to the circuit switched counterparts in CEN/TS 17184 and tests for conformance are found

in CEN/TS 17240.
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Figure 2 — Overview: eCall using IMS compared to eCall over CS

Each set of standards is exclusive to the specific switching type (domain) and based on the requirement

that every network will, in principle, be able to handle and route an eCall. That requirement is both a

technical requirement and a regulatory requirement.

In the foreseeable future, the PLMNs provided by packet switched networks will replace the circuit

switched GSM/UMTS networks, but until then there will be a hybrid situation in which either one or more

circuit switched networks are available (and no packet switched), the other way around (packet switched

but no circuit switched) or both. This document describes the additional HLAP requirements for these

hybrid situations, conformance to which can be tested by following the tests described in the

accompanying CEN/TS YYYYY.
7 Requirements
7.1 General

This document specifies requirements additional to those laid down in EN 16062 and CEN/TS 17184

whilst trying to minimize duplication. Most requirements are linked to domain selection, fallback

scenarios etc. Where possible clauses in this document carry the same name as in forenamed documents.

7.2 General requirements
7.2.1 Enabled IVS

The following requirements apply to an IVS responsible for the eCall system that has not been disabled.

An IVS responsible for the eCall system that has been developed for operation in a hybrid situation shall

internally combine a ‘circuit switched network stack’, a ‘packet switched network stack’ and a ‘hybrid

business logic’ as shown in Figure 3.
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Figure 3 — IVS supporting eCall in a hybrid communication capabilities situation

The circuit switching network stack shall be conformant to the requirements set out in EN 16062 and the

packet switching network stack shall be conformant to those in CEN/TS 17184. The complete IVS shall

also be conformant to the requirements for the additional hybrid domain business logic which are laid

out in this document.

Although both stacks need to do periodic background scans to inform the additional business logic about

the availability and capabilities of networks, at no time shall there be more than one stack actively

involved in a call.
7.2.2 Enabled PSAP

The network operators will route calls based on either the TS12 register (circuit switched networks) or

the destination URN (packet switched IMS enabled networks) to the most appropriate PSAP. A fully

enabled PSAP shall make endpoints available for in-band transfer of the MSD (conformant to EN 16062)

and MSD transfer as part of the session establishment (conformant to CEN/TS 17184). Such PSAP shall

also be conformant to the requirements for the additional hybrid domain business logic which are laid

out in this document.

NOTE A PSAP does not need to be fully enabled, which means that it either supports in-band transfer or eCall

using IMS. Such PSAP does not fall within the scope of this document.
7.2.3 Self-test

On power up, the IVS responsible for the eCall system that has been developed for operation in the hybrid

situation shall normally perform the self-tests of both the circuit switched network stack and the packet

switched network stack as described in EN 1
...