Overview
ISO/IEC 13250-2:2006 - "Information technology - Topic Maps - Part 2: Data model" defines the abstract Topic Maps data model used to represent knowledge structures. It specifies the metamodel (using the XML Information Set formalism), the interpretation of topic maps, rules for merging topic maps, and a set of core subject identifiers. The standard’s purpose is to define how Topic Maps interchange syntaxes should be interpreted and to provide a foundation for supporting standards such as canonicalization, querying and constraints.
Key Topics
- Metamodel & information items: Topic Maps are described as a set of information items (topic items, topic name items, occurrence items, association items, etc.) each with named properties and well-defined equality tests.
- Locators & datatypes: Use of locators (URIs/IRIs) and constrained datatypes consistent with XML Infoset and relevant IETF/W3C standards.
- Core construct types: Definitions and semantics for topics, topic names, variant names, occurrences, associations, and association roles.
- Scope & reification: Formal treatment of context (scope) for statements and of reification (topics representing other constructs).
- Merging rules: Clear rules for eliminating redundant constructs when combining topic maps - including how topics, names, variants, occurrences and associations are merged.
- Core subject identifiers: A baseline set of subject identifiers and canonical relationships (type–instance, supertype–subtype, sort names, default name type) to promote consistent interpretation.
- Constraints & computed properties: Model includes constraints to avoid inconsistencies, and some properties may be computed from others to reflect semantics more clearly.
Applications & Who Uses It
- Knowledge architects and ontologists designing interoperable knowledge representations.
- Software developers building Topic Maps engines, indexers, or tools for authoring, merging and canonicalizing topic maps.
- Information managers and CMS integrators who need consistent metadata linking and subject identification across repositories.
- Search and semantic systems that map topics to information resources (occurrences) or model relationships (associations).
Practical benefits include improved interoperability of metadata, robust merging of distributed topic maps, and a stable foundation for query and canonicalization tools.
Related Standards
- ISO/IEC 13250 Part 3: XML syntax (Topic Maps interchange)
- ISO/IEC 13250 Part 4: Canonicalization
- XML Infoset, XML 1.0, XML Schema; RFC 3986 (URI), RFC 3987 (IRI); Unicode / ISO 10646
Keywords: Topic Maps, ISO/IEC 13250-2, data model, merging, subject identifiers, associations, occurrences, topic names, canonicalization, XML Infoset.