ISO 24531:2013

Overview

ISO 24531:2013 - "Intelligent transport systems - System architecture, taxonomy and terminology - Using XML in ITS standards, data registries and data dictionaries" - defines a consistent framework for using XML and its variants across Intelligent Transport Systems (ITS). The standard helps ITS standards developers and users specify XML-based data exchanges, register and manage XML schema constructs in ITS data registries and data dictionaries, and align XML with ASN.1 representations required by related ITS standards.

Key topics and requirements

• Consistent XML rules: Clause 7 prescribes required conditions, items and rules for modelling data exchanges and for using XML in ITS standards to maximise interoperability and reuse.
• Schema registration and management: Clause 8 describes objectives and rules for registering XML schema constructs in ITS data registries/data dictionaries, and how schema constructs map to ISO 14817/ISO 14818 constructs.
• Guidance and examples: The standard includes normative and informative annexes with XML schema patterns, message components, example request/response schemas, transformation files (XSLT), and code-list handling (Genericode).
• Interoperability focus: ISO 24531 is a conceptual model - it does not mandate a single physical implementation but requires consistent design choices to claim conformance.
• Integration with ASN.1 and UML: Provides guidance on elaborating XML from ASN.1 data definitions and aligns with UML modelling practices where relevant.
• Normative references: Refers to W3C XML/XSD/XLink/XSLT recommendations, OASIS Genericode, and ISO ITS registry standards (e.g., ISO 14817).

Applications

• Standardising XML message formats and schemas for ITS services such as traffic management, traveler information, and data exchange between transport centres.
• Creating and maintaining ITS data registries and data dictionaries to ensure consistent metadata, value domains and message definitions.
• Defining transformation workflows (e.g., XSLT) and schema mappings between XML and ASN.1 for systems that use hybrid encodings.
• Supporting regional or national ITS implementations by providing a reusable framework that allows local schema extensions while preserving international interoperability.

Who should use this standard

• ITS standards developers and working groups creating XML message specifications.
• System architects and data modelers implementing ITS data registries/data dictionaries.
• Software engineers and integrators building ITS applications, XML schemas, XSLT transformations, or ASN.1-to-XML mappings.
• Policy-makers and procurement teams requiring interoperable ITS data exchange specifications.

Related standards

• ISO 14817 (ITS data registry and data dictionary)
• ISO 14818/14813-6 (ASN.1/UML comparisons)
• W3C XML/XSD/XSLT recommendations
• OASIS Genericode (code-list representation)

Using ISO 24531:2013 helps ensure interoperable, maintainable and reusable XML-based data exchanges across intelligent transport systems worldwide.