Overview - ISO/IEC 20944-2:2013 (MDR-IB Part 2: Coding bindings)
ISO/IEC 20944-2:2013 is part of the Metadata Registries Interoperability and Bindings (MDR-IB) family. It specifies coding bindings and common provisions for mapping metadata-registry data instances into code-level representations. The standard defines a coding‑independent representation (CIR) concept, common datatypes and aggregates, navigation semantics, and two concrete coding bindings: XML and DIVP (Dotted Identifier Value Pair). It is intended to enable interoperable exchange of metadata and data instances between metadata registries (e.g., those based on ISO/IEC 11179) and consuming applications.
Key technical topics and requirements
- Abstract model: Defines a two-part conceptual model - a data structuring model (atomic objects, aggregates, datatypes) and a navigation model for addressing components within data objects.
- Datatypes: Uses and requires support for ISO/IEC 11404 general-purpose datatypes (basic types, type parameters, type operators).
- Aggregate structures: Supports arrays, records and nested aggregates; components may be ordered/unnamed or named/typed.
- Navigation and identifiers: Provides hierarchical naming, designation and navigation mechanisms to reference elements inside complex data objects.
- Properties and metadata: Supports property lists attached to data objects (system and user properties, such as _type, _shape, _last_modified).
- Bindings: Maps coding‑independent semantics to coding‑specific representations; includes XML coding binding (for integration with XML technologies) and DIVP coding binding (for name-value pair environments like scripting, email, web servers).
- Conformance: Defines conformance paradigms, data-instance and application conformance, and conformance labels to mark compliance with binding profiles.
- Extensibility & encoding: Covers handling of character encodings, exceptions and extensibility mechanisms per binding.
Practical applications and who uses it
- Metadata registry implementers: Build registries compatible with ISO/IEC 11179 and MDR-IB to expose metadata and data instances.
- Enterprise data architects & integrators: Enable consistent interchange of typed data across systems using XML or lightweight DIVP encodings.
- Software developers / API designers: Implement coding bindings that preserve metadata semantics and support conformance testing.
- System integrators / middleware vendors: Map CIR to various encodings (XML, DIVP, ASN.1, etc.) to achieve interoperability.
- Typical use cases: registry-to-registry synchronization, metadata-driven data exchange, lightweight scripting-based integrations and XML-based enterprise services.
Related standards
Benefits include improved metadata interoperability, consistent datatype handling, and transferable mappings between coding formats (e.g., XML ↔ DIVP) while preserving registry semantics.