ISO/IEC 21823-1:2019

Internet of Things (IoT) - Interoperability for IoT systems - Part 1: Framework

ISO/IEC 21823-1:2019(E) provides an overview of interoperability as it applies to IoT systems and a framework for interoperability for IoT systems. This document enables IoT systems to be built in such a way that the entities of the IoT system are able to exchange information and mutually use the information in an efficient way. This document enables peer-to-peer interoperability between separate IoT systems. This document provides a common understanding of interoperability as it applies to IoT systems and the various entities within them.

General Information

• Status: Published
• Publication Date: 14-Feb-2019
• ICS: 33.020 - Telecommunications in general
• Technical Committee: ISO/IEC JTC 1/SC 41 - Internet of Things and Digital Twin
• Drafting Committee: WG 4 - ISO/IEC JTC 1/SC 41/WG 4
• Current Stage: PPUB - Publication issued
• Start Date: 15-Feb-2019
• Completion Date: 15-Mar-2019

Overview

ISO/IEC 21823-1:2019 - "Internet of Things (IoT) - Interoperability for IoT systems - Part 1: Framework" defines a common framework and terminology for achieving interoperability across IoT systems. The standard explains how IoT entities (devices, gateways, services) can exchange information and mutually use it efficiently, including enabling peer-to-peer interoperability between separate IoT systems. It aligns interoperability considerations with the IoT reference architecture (see ISO/IEC 30141) and provides a facet model to guide design and assessment.

Key topics

• Interoperability definition and scope: Common understanding of interoperability for IoT systems and entities.
• Facet model: Five interoperability facets are described:
  • Transport interoperability - using an established communication infrastructure.
  • Syntactic interoperability - agreed data formats and encodings.
  • Semantic interoperability - shared meaning of data models in a subject area.
  • Behavioural interoperability - interactions produce expected outcomes.
  • Policy interoperability - compliance with legal, organizational and policy constraints.
• IoT characteristics and considerations: Network communication, discoverability, unique identification, network connectivity, legacy support, heterogeneity, security aspects (confidentiality, integrity, protection of PII), and compliance.
• Framework mapping: Context for interoperability within and between IoT systems and mapping to entities and interactions described in ISO/IEC 30141.
• Terminology and definitions: Standardized terms (e.g., interface, operation, framework) to promote consistent use across projects and organizations.

Applications

ISO/IEC 21823-1 is practical for organizations and professionals who design, deploy, procure or govern IoT solutions:

• System architects and integrators - to design interoperable architectures and select compatible interfaces and components.
• Device and gateway manufacturers - to ensure devices support the necessary discovery, identification and data formats for multi-vendor ecosystems.
• Platform and middleware providers - to align transport and syntactic layers with interoperability needs and to design semantic models and APIs.
• Security and compliance teams - to integrate policy interoperability and PII protection into system design.
• Procurement and standards bodies - to define interoperability requirements when sourcing IoT solutions.

Practical uses include multi-vendor deployments, smart city integrations, industrial IoT edge-to-cloud interactions, and cross-domain data sharing where consistent semantics, behaviour and policy compliance are required.

Related standards

• ISO/IEC 30141 - IoT Reference Architecture (referenced by 21823-1)
• ISO/IEC 21823 series - additional parts address specific interoperability facets in more detail

Keywords: ISO/IEC 21823-1:2019, IoT interoperability, interoperability framework, semantic interoperability, transport interoperability, syntactic interoperability, policy interoperability, ISO/IEC 30141.

Standards Content (Sample)

ISO/IEC 21823-1
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
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Internet of things (IoT) – Interoperability for iot systems –
Part 1: Framework
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ISO/IEC 21823-1
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
colour
inside
Internet of things (IoT) – Interoperability for iot systems –

Part 1: Framework
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.020 ISBN 978-2-8322-6567-3

– 2 – ISO/IEC 21823-1:2019 © ISO/IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Abbreviated terms . 8
5 Overview of Internet of Things interoperability . 8
5.1 Descriptions . 8
5.2 Considerations for Internet of Things interoperability . 8
5.3 Internet of Things interoperability facet model . 9
5.3.1 General . 9
5.3.2 Transport interoperability . 10
5.3.3 Syntactic interoperability . 10
5.3.4 Semantic interoperability . 11
5.3.5 Behavioural interoperability . 11
5.3.6 Policy interoperability . 11
5.3.7 Summary of Internet of Things interoperability facet model . 11
5.4 Issues affecting Internet of Things interoperability . 12
6 Consideration of the interoperability requirement for IoT characteristics . 13
6.1 General descriptions . 13
6.2 IoT system characteristics. 13
6.2.1 Network communication . 13
6.2.2 Self-description . 13
6.2.3 Other IoT system characteristics not considered in interoperability . 13
6.3 IoT component characteristics . 14
6.3.1 Discoverability . 14
6.3.2 Network connectivity . 14
6.3.3 Unique identification . 14
6.3.4 Other IoT component characteristics not considered in interoperability . 14
6.4 Legacy support . 14
6.5 Security . 14
6.5.1 Confidentiality . 14
6.5.2 Integrity . 14
6.5.3 Protection of personally identifiable information . 14
6.6 Heterogeneity . 14
6.7 Compliance . 14
6.8 Other IoT characteristics not considered in interoperability . 15
7 Framework for interoperable IoT systems based on IoT reference architecture . 15
7.1 Context for interoperability within and between IoT systems . 15
7.2 General description . 16
7.3 Interoperability of IoT entities . 17
Annex A (informative) Overall IoT infrastructure at high-level . 18
Bibliography . 20

Figure 1 – Facets of IoT interoperability . 10
Figure 2 – Entities and interactions in IoT systems . 15
Figure 3 – Concepts for interoperability of IoT entities . 16
Figure A.1 – Integration of an IoT system with others . 18
Figure A.2 – An overall IoT infrastructure . 19

Table 1 – Summary of different facets of IoT interoperability [1] . 12

– 4 – ISO/IEC 21823-1:2019 © ISO/IEC 2019
INTERNET OF THINGS (IoT) –
INTEROPERABILITY FOR IoT SYSTEMS –

Part 1: Framework
FOREWORD
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International Standard ISO/IEC 21823-1 was prepared by subcommittee 41: Internet of Things
and related technologies, of ISO/IEC joint technical committee 1: Information technology.
The list of all currently available parts of the ISO/IEC 21823 series, under the general title
Information technology – Internet of Things (IoT) – Interoperability for IoT systems, can be
found on the IEC and ISO websites.
The text of this standard is based on the following documents:
FDIS Report on voting
JTC1-SC41/75/FDIS JTC1-SC41/87/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

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INTRODUCTION
Internet of Things (IoT) systems involve communications between different entities. This
applies to connections between different IoT systems. It also applies to the many connections
that exist within IoT systems. The various entities and their connections are described in
ISO/IEC 30141.
The ISO/IEC 21823 series addresses issues that relate to interoperability of the
communications between IoT systems entities. ISO/IEC 21823-1 describes a general
framework for interoperability of IoT systems. This includes a facet model for interoperability
which includes five facets of interoperability (i.e. transport, syntactic, semantic, behavioural
and policy). This document addresses the framework to achieve interoperability for IoT; the
specific facets are addressed in other parts of ISO/IEC 21823.

– 6 – ISO/IEC 21823-1:2019 © ISO/IEC 2019
INTERNET OF THINGS (IoT) –
INTEROPERABILITY FOR IoT SYSTEMS –

Part 1: Framework
1 Scope
This document provides an overview of interoperability as it applies to IoT systems and a
framework for interoperability for IoT systems. This document enables IoT systems to be built
in such a way that the entities of the IoT system are able to exchange information and
mutually use the information in an efficient way. This document enables peer-to-peer
interoperability between separate IoT systems.
This document ensures that all parties involved in building and using IoT systems have a
common understanding of interoperability as it applies to IoT systems and the various entities
within 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.
ISO/IEC 30141, Internet of Things (IoT) – Reference architecture
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 http://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/
3.1
interface
named set of operations that characterize the behaviour of an entity
[SOURCE: ISO 19142:2010, 4.10]
3.2
operation
specification of a transformation or query that an object may be called to execute
[SOURCE: ISO 19142:2010, 4.17]
3.3
framework
structure of processes and specifications designed to support the accomplishment of a
specific task
[SOURCE: ISO/IEEE 11073-10201:2004, 3.22]

3.4
interoperability
ability for two or more systems or applications to exchange information and to mutually use
the information that has been exchanged
[SOURCE: ISO/IEC 17788:2014, 3.1.5]
3.5
transport interoperability
interoperability (3.4) where information exchange uses an established communication
infrastructure between the participating systems
Note 1 to entry: System means IoT system.
Note 2 to entry: IoT device, IoT gateway, sensor and actuator are considered as a system.
[SOURCE: ISO/IEC 19941:2017, 3.1.3]
3.6
syntactic interoperability
interoperability (3.4) such that the formats of the exchanged information can be understood by
the participating systems
Note 1 to entry: System means IoT system.
Note 2 to entry: IoT device, IoT gateway, sensor and actuator are considered as a system.
[SOURCE: ISO/IEC 19941:2017, 3.1.4
3.7
behavioural interoperability
interoperability (3.4) so that the actual result achieves the expected outcome
Note 1 to entry: System means IoT system.
Note 2 to entry: IoT device, IoT gateway, sensor and actuator are considered as a system.
[SOURCE: ISO/IEC 19941:2017, 3.1.6, modified – In the definition, "result of the exchange"
has been replaced with "result".]
3.8
policy interoperability
interoperability (3.4) while complying with the legal, organizational, and policy frameworks
applicable to the participating systems
Note 1 to entry: System means IoT system.
Note 2 to entry: IoT device, IoT gateway, sensor and actuator are considered as a system.
[SOURCE: ISO/IEC 19941:2017, 3.1.7]
3.9
semantic interoperability
interoperability (3.4) so that the meaning of the data model within the context of a subject
area is understood by the participating systems
Note 1 to entry: System means IoT system.
Note 2 to entry: IoT device, IoT gateway, sensor and actuator are considered as a system.
[SOURCE: ISO/IEC 19941:2017, 3.1.5, modified – The term "semantic data interoperability"
has been replaced with "semantic interoperability".]

– 8 – ISO/IEC 21823-1:2019 © ISO/IEC 2019
4 Abbreviated terms
AMQP Advanced Message Queuing Protocol
API Application Programming Interface
ASD Application & Service Domain
IoT Internet of Things
JSON JavaScript Object Notation
MQTT Message Queuing Telemetry Transport
OMD Operation & Management Domain
PII Personally Identifiable Information
RAID Resource Access & Interchange Domain
SCD Sensing & Controlling Domain
UD User Domain
PED Physical Entity Domain
5 Overview of Internet of Things interoperability
5.1 Descriptions
Clause 5 provides an overview and facet models for Internet of Things interoperability. The
goal is to ensure that parties involved in the IoT, particularly as specified in ISO/IEC 30141,
have a common understanding of IoT interoperability for their specific needs. This common
understanding helps to achieve interoperability in IoT by establishing common terminology
and concepts used to describe it, particularly as they relate to IoT entities.
5.2 Considerations for Internet of Things interoperability
Interoperability can be defined as a measure of the degree to which various kinds of systems
or components interact successfully. For the purposes of this document, interoperability is
defined in 3.4. In the context of IoT, interoperability is further described as the successful
interaction among the IoT entities specified in ISO/IEC 30141.
Interoperability, in the context of IoT, involves a number of different types of interacting
entities and their associated interfaces. While interoperability matters in sectors throughout
the economy, this document specifically focuses on the context of IoT and especially relating
to the framework for interoperability based on the IoT reference architecture defined in
ISO/IEC 30141.
There are many considerations when addressing IoT interoperability. These include:
• ability for communication between entities in different domains or between different IoT
systems;
• ability for the exchange of data between entities in different domains or between different
IoT systems;
• ability of an understanding of the meaning of exchanged data between entities in different
domains or different IoT systems;
• ability for an IoT service to work with other IoT services;
• roles and activities of functional components as defined in ISO/IEC 30141 for
interoperability.
By taking these considerations into account, this document provides a context of framework
for a better understanding of existing and future interoperability standards.

5.3 Internet of Things interoperability facet model
5.3.1 General
Interoperability involves a number of elements, starting at the simple exchange of data bytes,
facilitating an understanding of the semantics of the exchanged information, and also an
alignment of the business processes, behaviour and policies on either side of the exchange.
Semantic, behavioural and policy interoperability can result in a significantly bigger challenge
than the bits and bytes. [1]
In dealing with the various interactions to which interoperability applies in IoT, it is necessary
to explore technological, information and human aspects. Moving forward, interoperability
related challenges are likely to intensify and get more difficult to manage as IoT systems grow
more complex and interconnected. In IoT systems where anything can be connected, the
complexities are further extended from technological aspects to global policies, regulation and
international law.
To discuss interoperability within the context of IoT, it is necessary to deal with different
perspectives of conceptual interoperability and identify with whom, with what, and
circumstances in which interoperability plays a vital role. This document describes these
various aspects of interoperability in terms of facets. Interoperability of two entities may be
described in terms of different facets, where each facet focuses on one aspect of
interoperability. To achieve interoperability, it is important th
...