A brief overview of the Open Archives Initiative Steve Hitchcock Open Citation Project (OpCit) Southampton University Prepared for Z39.50/OAI/OpenURL plenary session at the JISC DNER All-Projects Synthesis Meeting, Manchester. 24 January 2002
OAi timeline Conceived as the Universal Preprint Service (UPS) Oct First meeting in Santa Fe, NM, a forum to discuss and solve matters of interoperability between author self-archiving solutions. Re-named the Open Archives Initiative. Feb Santa Fe Convention released, defining the technical and organizational framework. Sept OAi extends interoperability framework beyond eprints - develops and promotes interoperability standards that aim to facilitate the efficient dissemination of content - and appoints steering committee.
OAi technical framework Feb Santa Fe Convention, defines: – Open Archives Metadata Set – Harvesting interface based on a subset of the Dienst protocol – two classes of participants data providers expose metadata about content service providers issue protocol requests to data providers Jan OAI Metadata Harvesting Protocol (MHP) Version 1.0, an application-independent interoperability framework that can be used by a variety of communities engaged in publishing content on the Web Jun MHP Version 1.1 updated for W3C XML Schema specification recommendation of May 2001
Key papers on OAi Carl Lagoze and Herbert Van de Sompel The Open Archives Initiative: Building a low-barrier interoperability framework. Joint Conference on Digital Libraries Roanoke, VA, June, Clifford A. Lynch Metadata Harvesting and the Open Archives Initiative. ARL Bimonthly Report, No. 217, August For more papers see Perspectives on Electronic Publishing on OAi opicalTerms&keyword=Open%20Archives%20initiative&
OAi: key architectural decisions From Lynch (2001) Participants at Santa Fe made a key architectural decision: they adopted a model that rejected distributed search in favor of simply having servers provide metadata in bulk for harvesting services The Santa Fe group wanted a very simple, low-barrier-to-entry interface, and to shift implementation complexity and operational processing load away from the repositories and to the developers of federated search services, repository redistribution services, and the like.
OAi metadata All OAI data providers supply metadata in a common format – the unqualified Dublin Core Metadata Element Set In the spirit of experimentation, all elements remain optional Parallel metadata sets: no limitations on the nature of such sets, other than that the metadata records be structured as XML documents, which have a corresponding XML schema for validation
OAi Metadata Harvesting Protocol Six requests or verbs carried within HTTP POST or GET methods: GetRecord Required arguments specify the identifier, or key, of the requested record and the format of the metadata that should be included Identify Information about a repository ListIdentifier Retrieve the identifiers of records that can be harvested from a repository. Optional arguments permit selectivity ListMetadataFormats ListRecords ListSets
OAi MHP or Z39.50? More from Lynch (2001) We should not think about the world becoming partitioned between Z based resources and MHP-speaking resources, but rather about bridges and gateways. It is quite reasonable to think about a service that is constructed using the Open Archives Metadata Harvesting Protocol offering a Z39.50 interface to its user community. A Z39.50-speaking server can fairly easily be made MHP-compliant, and I would expect to see the development of gateway or broker services that make Z39.50 servers available for open archives metadata harvesting in cases where the individual server operators do not want to undertake this development work.
The future for OAi Is OAi an initiative or a protocol? Who will use it – eprints services, digital libraries, publishers? Will OAi be standardised? To follow OAi developments see Open Archives Initiative Web site OpCit news A copy of these slides will be found on the OpCit site Look for Papers and presentations