Overview
ISO 17316:2015 defines the International Standard Link Identifier (ISLI) - a persistent identifier system for links between entities in the information and documentation domain. An ISLI identifies a directed relationship between two entities (sources and targets) such as documents, media resources, people, times or places. The standard specifies the identifier structure, metadata requirements, allocation and assignment principles, and the role of the ISLI registration authority. It does not mandate any particular technology for representing or implementing links and does not change content ownership or access rights.
Key topics and technical requirements
- Identifier structure
- Three numeric fields: service field (6 digits), link field (variable length), check digit (1 digit).
- Human-readable form prefixed with “ISLI” and hyphens (hyphens/“ISLI” are not part of the identifier).
- Allocation and assignment
- Service codes are allocated by the registration authority to a specific class of links (one service = one service code; codes are permanent).
- ISLI codes are assigned to individual links within a service; each code is unique and permanent (may be cancelled but not reused).
- Metadata requirements
- Each ISLI must be registered with kernel descriptive metadata (source/target types, names, optional fragments) and administrative metadata (registrant, allocation date, contact, cancellation info). Full metadata schema is defined by the registration authority (Annex B).
- Administration
- A designated ISLI registration authority administers code allocation, assignment, public registers, and resolution/query services (Annex C).
- Integrity
- A check digit protects against errors; calculation method is specified (Annex D).
- Design principles
- Prefer use of existing identifiers (e.g., ISMN shown in examples) to represent sources/targets; ISLI identifies links, not entities.
Applications and who uses it
ISO 17316 (ISLI) is useful where interoperable, persistent identification of relationships is needed:
- Digital libraries and archival systems linking manuscripts, scores, recordings, and annotations
- Multimedia platforms associating audio/video fragments with textual or score sources
- Educational content platforms, accessibility services, and publishing ecosystems that render related resources jointly
- Metadata aggregators, registrars, and service providers implementing cross-system link resolution
Primary users: librarians, publishers, metadata specialists, digital repository managers, standards registrars, and software developers building interoperable linking/resolution services.
Related standards
- ISO 17316 recommends using existing ISO identifiers for entities where appropriate (examples in the standard include ISMN). Implementers often integrate ISLI with other identifier schemes and metadata standards to support robust interoperability.