ISO/IEC 21823-4:2022

Internet of Things (IoT) - Interoperability for IoT systems - Part 4: Syntactic interoperability

ISO/IEC 21823-4:2022 specifies the IoT interoperability from a syntactic point of view. In ISO/IEC 21823-1: Framework [2], five facets are described for IoT interoperability, i.e. transport, semantic, syntactic, behavioural and policy. In this document, the following specifications for IoT interoperability from syntactic viewpoint are included;
– A principle of how to achieve syntactic interoperability among IoT systems which include IoT devices
– Requirements on information related to IoT devices for syntactic interoperability
– A framework for processes on developing information exchange rules related to IoT devices from the syntactic viewpoint

General Information

• Status: Published
• Publication Date: 08-Mar-2022
• 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: 18-Mar-2022
• Completion Date: 09-Mar-2022

Standards Content (Sample)

ISO/IEC 21823-4
Edition 1.0 2022-03
INTERNATIONAL
STANDARD
colour
inside
Internet of things (IoT) – Interoperability for IoT systems –
Part 4: Syntactic interoperability

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ISO/IEC 21823-4
Edition 1.0 2022-03
INTERNATIONAL
STANDARD
colour
inside
Internet of things (IoT) – Interoperability for IoT systems –

Part 4: Syntactic interoperability

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.020 ISBN 978-2-8322-1083-4

– 2 – ISO/IEC 21823-4:2022 © ISO/IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Abbreviated terms . 7
5 Principle for IoT syntactic interoperability . 7
5.1 General . 7
5.2 Principle for IoT syntactic interoperability . 7
5.3 Relevant technologies for syntactic interoperability . 8
5.3.1 Metamodel and syntactic interoperability . 8
5.3.2 Metamodel-driven approaches supporting interoperability issues . 9
5.4 The overall structure of the proposed approach . 9
5.5 The methodology of metamodel-driven information exchange . 10
5.6 Information exchange rules . 11
5.6.1 Categories of information exchange rules . 11
5.6.2 Information exchange rules expression . 12
5.6.3 Information exchange rules expression example . 12
6 Requirements on information related to IoT devices . 12
6.1 General . 12
6.2 General requirements on the translation rules . 13
6.2.1 General . 13
6.2.2 Required intrinsic properties of physical IoT devices (IPIoT) . 13
6.2.3 Required extrinsic properties of physical IoT devices (EPIoT) . 14
6.3 General requirements on the operation rules . 15
6.3.1 Overview of mismatches between IoT systems . 15
6.3.2 Required properties and syntactic resolutions for potential IoT
mismatches . 17
6.3.3 Details of required properties and syntactic resolutions for potential IoT
mismatches . 18
7 A framework for IoT syntactic interoperability . 30
7.1 General . 30
7.2 A conceptual model for dataset of operation rules (DOR) . 31
7.3 Detailed procedures for a syntactic interoperability framework . 31
7.3.1 Procedure A to prepare the required properties and resolutions . 31
7.3.2 Procedure B to create information exchange rules (DIER) . 32
7.3.3 Procedure C to execute the information exchange rules and check the
result . 32
Annex A (informative) Properties for physical IoT devices and data . 33
A.1 Intrinsic properties of physical IoT devices . 33
A.2 Extrinsic properties of physical IoT devices . 35
Annex B (informative) A use case . 37
B.1 General . 37
B.2 The use case overview: Connected car and vehicle in smart city . 37
B.3 A scenario of this use case . 38
B.3.1 The architecture of this use case . 38

B.3.2 Scenario: Data exchange between a connected car and a traffic
management system (TMS) . 38
B.4 Examples used in this use case . 39
B.4.1 General . 39
B.4.2 Illustrated example files and their relationships . 40
Annex C (informative) Other metamodel definitions . 41
Bibliography . 42

Figure 1 – The overall structure of the proposed approach . 9
Figure 2 – Model hierarchies and metamodel-driven information exchange rules . 10
Figure 3 – Categories of information exchange rules . 11
Figure 4 – Excerpted information exchange rules for Annex B . 12
Figure 5 – Classifications of requirements on information related to IoT devices . 13
Figure 6 – A procedure for mismatch detection and resolution . 16
Figure 7 – An example of mismatch detection and resolution . 17
Figure 8 – A framework for processes on developing information exchange rules
related to IoT devices from the syntactic viewpoint . 30
Figure 9 – An excerpted conceptual model of DOR (dataset of operation rules) . 31
Figure 10 – Steps of Procedure A . 32
Figure B.1 – Overall view of use case 1 . 37
Figure B.2 – Architecture of connected car and vehicle in smart city use case . 38
Figure B.3 – Information exchange between a car and a TMS . 38
Figure B.4 – Relationships of example files for this use case . 40

Table 1 – Required intrinsic properties of physical IoT devices . 14
Table 2 – Required extrinsic properties of physical IoT devices . 15
Table 3 – Required properties and resolutions for potential IoT mismatches . 18
Table 4 – Mismatch1: Synchronization mismatch . 19
Table 5 – Mismatch2: Sampling frequency mismatch . 20
Table 6 – Mismatch3: Location mismatch . 21
Table 7 – Mismatch4: Data recording pattern mismatch . 22
Table 8 – Mismatch5: Precision mismatch. 23
Table 9 – Mismatch6: Significant figure mismatch . 24
Table 10 – Mismatch7:Range mismatch . 25
Table 11 – Mismatch8: Calibration mismatch . 26
Table 12 – Mismatch9: Response time mismatch . 27
Table 13 – Mismatch10: Acquisition status mismatch . 28
Table 14 – Mismatch11: Unit mismatch . 29
Table A.1 – Intrinsic properties of physical IoT devices . 33
Table A.2 – Extrinsic properties of physical IoT devices . 36
Table C.1 – Definitions of metamodel in various resources . 41

– 4 – ISO/IEC 21823-4:2022 © ISO/IEC 2022
INTERNET OF THINGS (IoT) –
INTEROPERABILITY FOR IoT SYSTEMS –

Part 4: Syntactic interoperability

FOREWORD
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