Overview
ISO/IEC 21000-21:2017 - Media Contract Ontology (MCO) - defines a machine-readable ontology for representing contracts within the MPEG-21 Multimedia Framework. The standard specifies semantic structures to express agreements governing transactions of MPEG-21 Digital Items and services (delivery, identification, encryption, search, etc.), and can also serve as an electronic contract format for media-rights trading beyond MPEG-21. MCO enables unambiguous, interoperable expression of permissions, prohibitions and obligations together with associated conditions, metadata, encryption and signatures to support automated contract processing and verification.
Key Topics and Requirements
- Semantic contract representation: A formal ontology (including OWL representation) to model contract entities, parties, clauses and relationships in a machine-readable form.
- Deontic expressions: Explicit modelling of permissions, obligations, and prohibitions, enabling software to interpret and enforce contractual rules.
- Conditions and facts: Specification of contractual conditions (e.g., temporal, technical or payment-related) that govern when rights or duties apply.
- Reference to MPEG content and services: Clear mechanisms to link contract terms to MPEG-21 Digital Items and associated services.
- Extension mechanism: Core ontology plus defined extensions (intellectual property rights exploitation, payments & notifications, Rights Expression Language acts) and a clear method to introduce future extensions.
- Security & evidence: Support for encryption of whole contracts or parts, metadata annotation, and proof of agreement through digital signatures.
- Formal definitions: Structured classes, object properties and datatype properties to ensure interoperability across systems.
- Interoperability with REL: Integration capability with ISO/IEC 21000-5 (Rights Expression Language) for expressing rights-related acts.
Applications and Who Uses It
- Media companies & content owners: Model licensing, distribution and exploitation agreements as structured, auditable contracts.
- Service providers & DRM vendors: Automate enforcement of delivery, encryption and access-control policies tied to contractual terms.
- Marketplaces & rights exchanges: Standardized electronic contract format for trading media rights across platforms.
- Legal-tech and compliance teams: Maintain machine-readable contract records to support audit, reporting and dispute resolution.
- Software developers & integrators: Build interoperable contract-aware applications that parse, validate and enforce MPEG-21 contracts.
Related Standards
- ISO/IEC 21000 (MPEG-21) series - multimedia framework
- ISO/IEC 21000-5 - Rights Expression Language (REL)
- ISO/IEC 21000-19 - Media Value Chain Ontology (MVCO)
- Other parts of MPEG-21 for Digital Item identification, packaging and delivery
ISO/IEC 21000-21:2017 is essential when you need standardized, semantic, machine-actionable contracts for multimedia assets and services - improving automation, interoperability and legal traceability in digital media ecosystems.
Open preview (PDF)Information technology — Multimedia framework (MPEG-21) — Part 21: Media contract ontology
