SIST-TP CEN ISO/TR 21186-2:2021
(Main)Cooperative intelligent transport systems (C-ITS) - Guidelines on the usage of standards - Part 2: Hybrid communications
Cooperative intelligent transport systems (C-ITS) - Guidelines on the usage of standards - Part 2: Hybrid communications
This document serves as a guideline explaining the concept of hybrid communications and support
functionalities for Cooperative ITS services deployed in conformance with the ITS station architecture
and related Cooperative ITS standards.
Kooperative intelligente Verkehrssyteme (C-ITS) - Leitfäden zur Nutzung von Normen - Teil 2: Hybride Kommunikation
Titre manque Partie 2: Titre manque
Kooperativni inteligentni transportni sistemi (C-ITS) - Smernice za uporabo standardov - 2. del: Hibridne komunikacije (ISO/TR 21186-2:2021)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TP CEN ISO/TR 21186-2:2021
01-maj-2021
Kooperativni inteligentni transportni sistemi (C-ITS) - Smernice za uporabo
standardov - 2. del: Hibridne komunikacije (ISO/TR 21186-2:2021)
Cooperative intelligent transport systems (C-ITS) - Guidelines on the usage of standards
- Part 2: Hybrid communications
Kooperative intelligente Verkehrssyteme (C-ITS) - Leitfäden zur Nutzung von Normen -
Teil 2: Hybride Kommunikation
Titre manque Partie 2: Titre manque
Ta slovenski standard je istoveten z: CEN ISO/TR 21186-2:2021
ICS:
01.120 Standardizacija. Splošna Standardization. General
pravila rules
03.220.01 Transport na splošno Transport in general
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
SIST-TP CEN ISO/TR 21186-2:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TP CEN ISO/TR 21186-2:2021
CEN ISO/TR 21186-2
TECHNICAL REPORT
RAPPORT TECHNIQUE
February 2021
TECHNISCHER BERICHT
ICS 03.220.01; 01.120; 35.240.60
English Version
Cooperative intelligent transport systems (C-ITS) -
Guidelines on the usage of standards - Part 2: Hybrid
communications (ISO/TR 21186-2:2021)
Systèmes de transport intelligents coopératifs (C-ITS) - Kooperative intelligente Verkehrssyteme (C-ITS) -
Lignes directrices sur l'utilisation des normes - Partie Leitfäden zur Nutzung von Normen - Teil 2: Hybride
2: Communications hybrides (ISO/TR 21186-2:2021) Kommunikation (ISO/TR 21186-2:2021)
This Technical Report was approved by CEN on 24 October 2020. It has been drawn up by the Technical Committee CEN/TC 278.
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, Turkey 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TR 21186-2:2021 E
worldwide for CEN national Members.
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CEN ISO/TR 21186-2:2021 (E)
Contents Page
European foreword . 3
2
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CEN ISO/TR 21186-2:2021 (E)
European foreword
This document (CEN ISO/TR 21186-2:2021) has been prepared by Technical Committee ISO/TC 204
"Intelligent transport systems" in collaboration with Technical Committee CEN/TC 278 “Intelligent
transport systems” the secretariat of which is held by NEN.
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.
Endorsement notice
The text of ISO/TR 21186-2:2021 has been approved by CEN as CEN ISO/TR 21186-2:2021 without any
modification.
3
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SIST-TP CEN ISO/TR 21186-2:2021
TECHNICAL ISO/TR
REPORT 21186-2
First edition
2021-02
Cooperative intelligent transport
systems (C-ITS) — Guidelines on the
usage of standards —
Part 2:
Hybrid communications
Systèmes de transport intelligents coopératifs (C-ITS) - Lignes
directrices sur l'utilisation des normes —
Partie 2: Communications hybrides
Reference number
ISO/TR 21186-2:2021(E)
©
ISO 2021
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ISO/TR 21186-2:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
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ISO/TR 21186-2:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 5
5 Motivations for hybrid communications support . 5
5.1 Connected and cooperative mobility . 5
5.2 Examples of use cases requiring a diversity of access technologies . 7
5.2.1 Road hazard notification (use case 1) . 7
5.2.2 Emergency call (use case 2) . 8
5.2.3 Public transport (use case 3) . 8
5.3 Hybrid communication technologies. 9
5.4 Unified communication and data management architecture . 9
5.4.1 Requirements for the unified communication and data management
architecture . 9
5.4.2 Supporting a diversity of applications with diverging communication needs .10
5.4.3 Supporting a diversity of communication paths .10
5.4.4 Supporting a diversity of access technologies and protocols.11
6 The ITS station architecture and functionalities in support of hybrid communications .12
6.1 Origins of the ITS station architecture .12
6.2 Detailed ITS station architecture .14
6.3 Design principles of the ITS station architecture .16
6.4 ITS station functionalities in support for hybrid communications .17
6.5 ITS station management entity .18
6.6 ITS station capabilities .19
6.7 ITS station service managed entity (ITS-S MSE) .20
6.8 Management of data flow types (ITS-S flow type) .22
6.9 Management of communication paths (ITS-S path) .22
6.10 Management of communication profiles (ITS-SCP) .22
6.11 Management of communication handovers .24
6.12 Management of globally unique identifiers .24
6.13 Standards necessary in support of hybrid communications .24
7 How to develop ITS application standards .25
7.1 Generic development principle .25
7.2 Specifying ITS-S application process .25
7.3 Defining data flow communication requirements .25
7.4 Registering communication requirements .26
7.5 Transmitting data .26
Bibliography .27
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 204, Intelligent transport systems, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC
278, Intelligent transport systems, in accordance with the Agreement on technical cooperation between
ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 21186 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
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Introduction
This document is part of a family of deliverables from Standard Development Organizations (SDOs)
for Cooperative Intelligent Transport Systems (C-ITS), which is a subset of standards for Intelligent
Transport Systems (ITS).
ITS aims to improve surface transportation in terms of:
— safety
e.g. crash avoidance, obstacle detection, emergency calls, dangerous goods;
— efficiency
e.g. navigation, green wave, priority, lane access control, contextual speed limits, car sharing;
— comfort
e.g. telematics, parking, electric vehicle charging, infotainment;
— sustainability
by applying information and communication technologies (ICT).
In the European Union, the legal framework is given by the European Commissions Mandate M/453
[53] [52]
on C-ITS , the European Commission Directive 2010/40 , and the European Commission Mandate
[54]
M/546 .
The whole set of standards for deployment of C-ITS is difficult to understand by developers of equipment
and software, especially ITS application software, and thus guidelines explaining a beneficial choice
of standards (C-ITS Release), the purpose and interaction of standardized features, beneficial
implementation approaches and guidance in developing ITS applications are a prerequisite for a fair
and open market allowing early deployment of interoperable and future-proof solutions.
The ISO 21186 series provides necessary guidelines in multiple parts, each dedicated to a specific
purpose:
[14]
— Part 1: Standardization landscape and releases ;
— Part 2: Hybrid communications (this document);
15]
— Part 3: Security .
This document can be complemented by further parts as required, for example:
— Usage of the service announcement protocol specified, for example, in ISO 22418;
— Dynamically extendable data and protocol parameters ("Information Object Classes" and
"Information Object Sets"; based on ASN.1 type CLASS);
1)
— Usage of the GTDM framework specified in ISO/TS 21184 .
The purpose of this document is thus to inform about relevant standards and to describe the
functionalities of the ITS station architecture defined in support for hybrid communication
technologies. It is intended to serve as a guideline to structure the development of new C-ITS standards
and to harmonize the deployment of C-ITS services relying on the use of hybrid communication
technologies. It also intends to give support to the developers of standards defining C-ITS services and
to the developers of C-ITS solutions and ITS applications complying with the ITS station architecture
and its set of functionalities supporting hybrid communications.
1) Under preparation. Stage at the time of publication: ISO/PRF TS 21184:2021.
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At time of writing this document, no applicable Intellectual Property Rights (IPR) issues were known
related to this document. However, this document references standards, for which IPRs are known.
Information on such IPRs is expected to be provided in those respective standards, which might be
from any one of the Standards Development Organisations working on ITS or C-ITS.
Referencing other SDOs and their respective deliverables in no way is to be understood as an
endorsement, but rather as an informative piece of information.
More details on the C-ITS domain can be found in the Brochure cited in Reference [58].
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TECHNICAL REPORT ISO/TR 21186-2:2021(E)
Cooperative intelligent transport systems (C-ITS) —
Guidelines on the usage of standards —
Part 2:
Hybrid communications
1 Scope
This document serves as a guideline explaining the concept of hybrid communications and support
functionalities for Cooperative ITS services deployed in conformance with the ITS station architecture
and related Cooperative ITS standards.
2 Normative references
There are no normative references in this document.
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:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
access technology
technology employed in a communication interface to access a specific medium
[SOURCE: ISO 21217:2020, 3.1]
3.2
communication adaptation layer
CAL
set of protocols and functions to adapt access technologies to the ITS-S networking and transport
layer (3.20)
[SOURCE: ISO 21217:2020, 3.3]
3.3
hybrid communications
composition of multiple access technologies and communication protocols combined to provide
complementary or redundant communication channels
[SOURCE: ISO 21217:2020, 3.7]
3.4
hybrid communication support
feature of an ITS station used to combine multiple access technologies and protocols
[SOURCE: ISO 21217:2020, 3.8]
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3.5
hybrid ITS service
ITS service that relies on hybrid communications (3.3)
[SOURCE: ISO 21217:2020, 3.9]
3.6
ITS station
ITS-S
functional entity comprised of an ITS-S facilities layer (3.13), ITS-S networking and transport layer (3.20),
ITS-S access layer (3.7), ITS-S management entity, ITS-S security entity and ITS-S applications (3.9) entity
providing ITS services
Note 1 to entry: From an abstract point of view, the term "ITS station" refers to a set of functionalities. The
term is often used to refer to an instantiation of these functionalities in a physical unit. Often, the appropriate
interpretation is obvious from the context. The proper name of the physical instantiation of an ITS-S is ITS
station unit (ITS-SU).
[SOURCE: ISO 21217:2020, 3.15]
3.7
ITS-S access layer
protocol layer in the ITS-S reference architecture containing the OSI physical and data link layer
protocols for ITS communications
[SOURCE: ISO 21217:2020, 3.16]
3.8
ITS-S access technology
access technology (3.1) dedicated to operation in an ITS station (3.6)
[SOURCE: ISO 21217:2020, 3.20]
3.9
ITS-S application
ITS-S application process (3.10) residing in the ITS-S application entity
[SOURCE: ISO 21217:2020, 3.21]
3.10
ITS-S application process
element in an ITS station (3.6) that performs information processing for a particular application and
uses ITS-S services to transmit and receive information
[SOURCE: ISO 21217:2020, 3.22]
3.11
ITS-S capability
uniquely addressable protocol or functionality that is part of an ITS-S managed service entity (3.19)
Note 1 to entry: Examples of ITS-S capabilities in the ITS station (3.6) facilities layer are generic ITS-S facilities
layer (3.13) services specified in ISO/TS 17429 (Communication Profile Handler, Facilities Services Handler,
Content Subscription Handler), the position and time service defined in ISO/TS 21176, the security services
defined in ISO/TS 21177; examples of ITS-S capabilities in the ITS-S networking and transport layer (3.20) are
IPv6 functionalities defined in ISO 21210 (IPv6 neighbour discovery, IPv6 forwarding, IPv6 mobility support,
etc.), the fast service announcement protocol defined in ISO 22418, etc.
[SOURCE: ISO 21217:2020, 3.24]
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3.12
ITS-S communication profile
ITS-SCP
parameterized ITS-S communication protocol stack (set of protocols composing all the ITS station (3.6)
layers) that allows communication end points to communicate with one another
[SOURCE: ISO 21217:2020, 3.25, modified.]
3.13
ITS-S facilities layer
layer in the ITS-S reference architecture containing OSI layers 5, 6 and 7 that connects applications to
the ITS-S networking and transport layer (3.20)
[SOURCE: ISO 21217:2020, 3.31]
3.14
ITS-S flow
identifiable sequence of packets of a given ITS-S flow type (3.16) transmitted between a source node
and a destination node.
[SOURCE: ISO 21217:2020, 3.36]
3.15
ITS-S flow identifier
identifier, being unique within an ITS station (3.6) unit, that identifies an ITS-S flow (3.14)
[SOURCE: ISO 24102-6:2018, 3.9]
3.16
ITS-S flow type
set of characteristics describing a data flow
[SOURCE: ISO 21217:2020, 3.37]
3.17
ITS-S flow type identifier
identifier being unique within the ITS station (3.6) that identifies an ITS-S flow type (3.16)
[SOURCE: ISO 24102-6:2018, 3.11]
3.18
ITS-S host
ITS-S node (3.21) comprised of ITS-S functionalities other than the functionalities of an ITS-S router
(3.23), ITS-S border router, ITS-S mobile router, or an ITS-S gateway
[SOURCE: ISO 21217:2020, 3.39]
3.19
ITS-S managed service entity
MSE
uniquely addressable entity in an ITS-S layer comprised of a set of related ITS-S capabilities
Note 1 to entry: Examples of ITS-S managed service entities are: a communication module in the ITS-S access
technologies layer (M5, cellular, etc.), a protocol suite in the ITS-S networking & transport layer (IPv6, FNTP,
GeoNetworking, 6LoWPAN, etc.), the generic facilities at the ITS-S facilities layer (3.13) (COH, FSH, CSH).
[SOURCE: ISO 21217:2020, 3.42]
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3.20
ITS-S networking and transport layer
layer in the ITS-S reference architecture containing OSI layers three and four that connects the ITS-S
facilities layer (3.13) to the ITS-S access layer (3.7)
[SOURCE: ISO 21217:2020, 3.46]
3.21
ITS-S node
node comprised of a set of functionalities in an ITS station (3.6) unit that is connected to the ITS station-
internal network or comprises an entire ITS station unit
[SOURCE: ISO 21217:2020, 3.47]
3.22
ITS-S path
directed sequence of nodes connected by links starting at a source node, traversing a communication
interface of the source ITS-S, an ITS-S ingress anchor node and an ITS-S egress anchor node, ending at a
destination node
[SOURCE: ISO 21217:2020, 3.48]
3.23
ITS-S router
ITS-S node (3.21) comprised of routing functionalities of an ITS station (3.6) unit used to connect two
networks and to forward packets not explicitly addressed to itself
[SOURCE: ISO 21217:2020, 3.49]
3.24
localized communications
communications with nearby stations without involving support of an infrastructure network
[SOURCE: ISO 21217:2020, 3.53]
3.25
networked communications
communications using support of an infrastructure network
[SOURCE: ISO 21217:2020, 3.60]
3.26
urban WiFi
short-range networked communications (3.25) WiFi access technology (3.1) used mostly in urban
environments and in personal devices such as smartphones, tablets and laptops
Note 1 to entry: An example of urban WiFi is IEEE 802.11 Basic Service Set (BSS) for WLAN access used in 2,4 GHz
or 5,4 GHz frequency range.
3.27
vehicular WiFi
short-range localized communications (3.24) WiFi access technology (3.1) specifically designed for
vehicular localized communications
Note 1 to entry: An example of vehicular WiFi is IEEE 802.11 operating outside the context of a Basic Service
[51]
(OCB), also known as IEEE 802.11p , used in the 5,9 GHz frequency range reserved for ITS services with profile
standards named ITS-G5 (ETSI) in Europe and Australia, and US-DSRC in North America and their harmonization
at ISO ( ITS-M5).
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4 Symbols and abbreviated terms
CAM cooperative awareness message
C-ITS cooperative intelligent transport systems
CPH communication profile handler
CSH content subscription handler
DENM decentralized environmental notification message
DSRC dedicated short-range communication
ETSI European Telecommunication Standards Institute
FSH facilities service handler
IEEE Institute of Electrical and Electronics Engineers
IPv6 internet protocol version 6
ITS intelligent transport systems
ITS-SU ITS station unit
LDM local dynamic map
LiFi light fidelity
LoRA long range
LTE-V2X long term evolution based vehicle-to-everything
OCB outside the context of a basic-service set
OSI open systems interconnection
PVT position, velocity and time
SDO standards development organization
US-DSRC american dedicated short range communication
V2X vehicle-to-vehicle and vehicle-to-roadside
WiFi wireless fidelity
WSMP wave short message protocol
5 Motivations for hybrid communications support
5.1 Connected and cooperative mobility
Intelligent transport systems (ITS) services are traditionally ranged into three categories: road traffic
safety, traffic efficiency and comfort (infotainment, value added services, etc.).
ITS services were initially deployed either in the roadside infrastructure (variable message signs, etc.),
in vehicles (telematics) or nomadic devices (navigation, traffic alerts, etc.) with little or no interaction
between the vehicles, other road users and the roadside infrastructure. With the advent of short-range
communication technologies, ITS services using the exchange of data between vehicles and the roadside
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[2],[36]-[38] [3]
infrastructure then started to appear (electronic fee collection , electric-vehicle charging ,
[39]
emergency call , etc.). These ITS services are specified to operate in a very controlled environment,
with a very specific radio technology, and for a very specific purpose.
While recent generations of vehicles are deployed with built-in communication systems providing
connectivity to remote platforms providing services (navigation, software update, telematics, electric
vehicle charging, emergency call, etc.), the forthcoming generation of vehicles will cooperate with
their surrounding environment (other vehicles, other road users, roadside infrastructure and urban
infrastructure). This localized exchange of data improves road safety (crash avoidance, obstacle
detection, etc.) and traffic efficiency (traffic information, green wave, lane access control, contextual
speed limit, etc.).
Cooperative ITS (C-ITS) services, i.e. ITS services for connected and cooperative mobility that rely on
the data exchanged between vehicles (cars, trucks, buses, etc.), other road users (pedestrians, cyclists,
etc.), the roadside and urban infrastructure (traffic lights, road tolls, etc.) and control and services
centres in the cloud (traffic control centre, service providers, map providers, etc.), and especially on the
sharing of data amongst service domains and applications of the same service domain, are thus being
developed. See Figure 1.
Figure 1 — Connected and Cooperative Mobility
However, distinct C-ITS services have diverging communication requirements (distribution area,
amount of data, delivery delay, privacy, confidentiality, etc.). No single communication technology is
able to fulfil all of these requirements at once.
Many communication technologies are available today on the market (cellular 3G/4G, infrared, LiFi,
satellite, urban WiFi, vehicular WiFi, LoRA, etc.) and new promising technologies appear regularly. They
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