ISO 22741-1:2022

Intelligent transport systems - Roadside modules AP-DATEX data interface - Part 1: Overview

Field devices are a key component in intelligent transport systems (ITS). Field devices include traffic signals, message signs, weather stations, traffic sensors, roadside equipment for connected ITS (C-ITS) environments, etc. Field devices often need to exchange information with other external entities. Field devices can be quite complex, necessitating the standardization of many data concepts for exchange. As such, the ISO 22741 series is divided into several individual Parts. This document (Part 1) introduces the ISO 22741 series and provides normative content that applies to the rest of the series.

Systèmes de transport intelligents — Interface de données AP-DATEX pour les modules en bord de route — Partie 1: Vue d'ensemble

General Information

• Status: Published
• Publication Date: 07-Feb-2022
• ICS: 03.220.20 - Road transport
• ICS: 35.240.60 - IT applications in transport
• Technical Committee: ISO/TC 204 - Intelligent transport systems
• Drafting Committee: ISO/TC 204/WG 9 - Integrated transport information, management and control
• Current Stage: 6060 - International Standard published
• Start Date: 08-Feb-2022
• Due Date: 19-Oct-2022
• Completion Date: 08-Feb-2022

Overview

ISO 22741-1:2022 - "Intelligent transport systems - Roadside modules AP‑DATEX data interface - Part 1: Overview" is the introductory, normative part of the ISO 22741 series. It defines the common rules, terminology and architecture used by subsequent parts that standardize data exchange for roadside field devices (traffic signals, message signs, weather stations, traffic sensors, C‑ITS roadside equipment, etc.). Part 1 sets out how AP‑DATEX conventions are applied to manage, monitor, configure and control field devices and provides core normative content that applies across the series.

Key topics and technical requirements

• Scope & purpose: Standardizes data concepts and exchange rules for intelligent transport systems (ITS) roadside modules and field‑to‑centre or field‑to‑field communications.
• Terminology & conventions: Defines common terms, ASN.1 presentation conventions and symbols to be used across the series.
• Architecture: Maps ISO 22741 services to ITS architectural services (see ISO 14813‑1) and explains AP‑DATEX usage scenarios.
• Conformance model: Explains how user needs, features and requirements are structured and traced; conformance codes (M = mandatory, O = optional) and option groups guide implementers.
• Data structures: Annex A provides normative data packet structures used by features defined in the series.
• Dialogues: Specifies generic dialogues used across parts - e.g., requesting information, publication of information - that implementations should support.
• Security: Discusses security considerations applicable to all conformant devices, including authentication, encryption and security recommendations; the abbreviations list references DTLS, TLS and IPsec as related transport/security technologies.

Practical applications

• Enables interoperable management and control of roadside modules by traffic management centres.
• Supports open procurement and non‑proprietary expansion of ITS deployments, reducing cost and deployment time.
• Facilitates device manufacturers, integrators and agencies in implementing consistent monitoring, configuration and control interfaces for:
  • Traffic signal controllers
  • Variable message signs
  • Roadside sensors and weather stations
  • C‑ITS roadside units and connected infrastructure

Who should use this standard

• ITS architects and system designers
• Traffic management authorities and operators
• Field device manufacturers and firmware developers
• Systems integrators and procurement/specification teams
• ITS standards and compliance assessors

Related standards

• ISO 15784‑3 - AP‑DATEX application profile for roadside modules (protocol expectations)
• ISO 14827‑2 - DATEX‑ASN data interfaces between transport centres
• ISO 14813‑1 - ITS architectural services referenced by ISO 22741

Keywords: ISO 22741-1:2022, Intelligent Transport Systems, AP‑DATEX, roadside modules, field devices, DATEX‑ASN, data interface, ITS security, conformance.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 22741-1
First edition
2022-02
Intelligent transport systems —
Roadside modules AP-DATEX data
interface —
Part 1:
Overview
Systèmes de transport intelligents — Interface de données AP-DATEX
pour les modules en bord de route —
Partie 1: Vue d'ensemble
Reference number
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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or ISO’s member body in the country of the requester.
ISO copyright office
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Phone: [phone]
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Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Conformance . 2
6 Conventions . 3
7 Architecture. 4
7.1 ITS services . . 4
7.2 ISO 22741 series architecture . 4
8 User needs . 4
9 Requirements . 5
9.1 Features . 5
9.2 Identifiable requirements . 5
9.3 Structure of data exchange requirements . 5
10 Dialogues . 5
10.1 Generic dialogues . 5
10.2 Requesting information . 5
10.3 Publication of information . 5
11 Security . 5
11.1 Authentication . 5
11.2 Encryption . 5
11.3 Security recommendation . 6
Annex A (normative) Data packet structures . 7
Bibliography . 8
iii
Foreword
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bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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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
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Any trade name used in this document is information given for the convenience of users and does not
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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.
A list of all parts in the ISO 22741 series 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.
iv
Introduction
0.1  Background
The need for standardized communication with field devices is growing around the world. Several
countries have already adopted application profile data exchange (AP-DATEX)-based field device
communication standards.
There is a growing opinion, supported by empirical evidence, that standardizing this activity will result
in improved intelligent transport service (ITS) performance, reduced cost, reduced deployment time
and improved maintainability. The ISO 22741 series extends ISO 15784-3 by defining the management
information necessary to monitor, configure and control features of field devices. The data elements
defined in all parts of the ISO 22741 series may be used with any protocol, but were designed with an
expectation that they would be used with one of the ISO 15784-3 protocols.
By using the approach described in this document, agencies can specify open procurements and
systems can be expanded geographically in an open and non-proprietary manner, which reduces the
costs, speeds and deployment, and simplifies the integration.
0.2  Overview
The AP-DATEX specified in ISO 15784-3, the International Standard for communication between traffic
management centres and field devices for traffic management, is suitable for use in the following cases:
a) Intelligent field devices with advanced functions communicate with the centre system each in
equal relation.
b) The exchanged data have a large size and relatively fixed structure.
c) The deterministic real time feature is not required but the efficient data exchange is required.
d) Field devices communicate with not only the centre system but also other field devices
simultaneously.
This document defines management information for field devices following the AP-DATEX conventions.
0.3  Document approach and layout
This document defines:
a) terminology and symbols used throughout the various parts of the ISO 22741 series (Clauses 3 and
4);
b) how conformance is defined in subsequent parts of the ISO 22741 series (Clause 5);
c) conventions used throughout the various parts of the ISO 22741 series (Clause 6);
d) the ITS architectural services defined in ISO 14813-1 that are addressed by the ISO 22741 series
(Clause 7);
e) the rules used by other parts of the ISO 22741 series in defining the user needs that drive the
definition of requirements (Clause 8);
f) the rules used by other parts of the ISO 22741 series in defining requirements and constraints
(Clause 9);
g) a set of generic dialogues that are referenced by other parts of the ISO 22741 series (Clause 10);
h) a discussion of security that applies to all devices conforming to the ISO 22741 series (Clause 11);
i) the data packet structures for the features defined by this document (Annex A).
v
0.4  Applicable environment
As depicted in Figure 1, all parts of the ISO 22741 series are intended to address data exchanges
between:
1) a management centre (traffic or otherwise) and a field device (roadside module), or
2) two field devices.
Key
1 interface
2 interface in the scope of this document
Figure 1 — Example of this AP-Scenario
Subsequent parts of the ISO 22741 series define needs, requirements and design details for various field
device capabilities.
vi
INTERNATIONAL STANDARD ISO 22741-1:2022(E)
Intelligent transport systems — Roadside modules AP-
DATEX data interface —
Part 1:
Overview
1 Scope
Field devices are a key component in intelligent transport systems (ITS). Field devices include traffic
signals, message signs, weather stations, traffic sensors, roadside equipment for connected ITS (C-ITS)
environments, etc.
Field devices often need to exchange information with other external entities. Field devices can be quite
complex, necessitating the standardization of many data concepts for exchange. As such, the ISO 22741
series is divided into several individual Parts. This document (Part 1) introduces the ISO 22741 series
and provides normative content that applies to the rest of the series.
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.
ISO 15784-3, Intelligent transport systems (ITS) — Data exchange involving roadside modules
communication — Part 3: Application profile-data exchange (AP-DATEX)
ISO 14827-2, Transport information and control systems — Data interfaces between centres for transport
information and control systems — Part 2: DATEX-ASN
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology
...