Examples
Worked examples
- Is an instance
A complex deposit comprising PDF, dataset, and a supplementary video bundled as an ORE Resource Map.
- Is an instance
A Fedora repository exposing object compositions as ORE Resource Maps.
Counter-examples
Looks similar, but isn't
- Not an instance
A zip file uploaded to a repository is not an ORE aggregation unless described by a Resource Map.
- Not an instance
An OAI-PMH metadata record alone is not an ORE object.
Editorial commentary
OAI-ORE (Object Reuse and Exchange) is a specification, from the same Open Archives Initiative that produced OAI-PMH, addressing a different problem: where OAI-PMH is concerned with batch harvesting of metadata records, ORE concerns the structure of compound digital objects whose components live at multiple, separately dereferenceable URLs — a research article, say, with a PDF, supplementary data files, figures, and a separate metadata record, each its own web resource.
The Resource Map
ORE defines the Resource Map (ReM) as a first-class, independently retrievable resource that describes an Aggregation — the set of Aggregated Resources that together make up the compound object — and the typed relationships between them. A Resource Map can be serialised in several standard formats depending on the consuming system: Atom, RDF/XML, RDFa, or JSON-LD, which lets ORE aggregations be consumed either as ordinary linked-data RDF or as a feed-style Atom document, whichever a given tool expects.
Where it is used
ORE underpins linked-data-style content exchange between repositories, and is used natively by Fedora Commons-based repository platforms and by several cross-repository aggregators that need to move a compound object’s full structure — not just a flat metadata record — between systems. The specification itself dates to 2008 (Lagoze, Van de Sompel, Nelson, Warner, Sanderson, and Johnston) and is a mature, stable spec rather than one under active revision; its core idea — a typed aggregation of related resources, independently addressable and machine-readable — has influenced later linked-data-for-repositories patterns.
How it differs from a structural-metadata format like METS
ORE and METS solve an overlapping problem — describing how a compound digital object’s parts relate to each other — from different starting points: METS is an XML schema, typically embedded in or alongside a single package, describing structural, administrative, and descriptive metadata for one object. ORE is RESTful and linked-data-native: the Resource Map is itself a dereferenceable web resource, consistent with the wider Open Archives Initiative and Linked Data approach of making every meaningful thing independently addressable rather than nested inside one package file.
References
- Lagoze C., Van de Sompel H., Nelson M., Warner S., Sanderson R., Johnston P., ‘Open Archives Initiative Object Reuse and Exchange Specifications’ (openarchives.org/ore/), 2008.
Also known as
Object Reuse and Exchange
Machine-readable encodings
Use in your systems
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