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Sharing With the Open Archives Initiative. Jenn Riley Metadata Librarian Indiana University. Purpose of Open Archives Initiative. “develops and promotes interoperability standards that aim to facilitate the efficient dissemination of content”
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Sharing With the Open Archives Initiative Jenn Riley Metadata Librarian Indiana University
Purpose of Open Archives Initiative • “develops and promotes interoperability standards that aim to facilitate the efficient dissemination of content” • “has its roots in the open access and institutional repository movements” • “Archive” defined broadly: “as a repository for stored information” Getty Technical Talk
Early history of the Open Archives Initiative • Originally defined a “metadata harvesting protocol” – OAI-PMH • Grew out of efforts to share e-prints • Original work supported by: • Digital Library Federation (DLF) • Coalition for Networked Information (CNI) • National Science Foundation (NSF) Getty Technical Talk
OAI-PMH • Protocol history • Version 1.0 released January 2001 • Version 1.1 released July 2001 • Version 2.0 released June 2002 • No further major revisions planned • Protocol for harvesting metadata, not content • No inherent assumption that the metadata describes digital content Getty Technical Talk
How OAI-PMH works Diagram from OAI for Beginners - the Open Archives Forum online tutorial at http://www.oaforum.org/tutorial/english/intro.htm Getty Technical Talk
Data providers • Set up a server that responds to harvesting requests • Required to expose metadata in simple Dublin Core (DC) format • Can supplement DC with metadata in any other format expressible with an XML schema (e.g., CDWA Lite) Getty Technical Talk
Service providers • Harvest and store metadata • Generally provide search/browse access to this metadata • Can be general or domain-specific • Can choose to collect metadata in formats other than DC • Can provide value-added services • Sometimes re-expose metadata to other aggregations Getty Technical Talk
Typical service provider behavior • Today • Collect and normalize metadata • Provide basic discovery • Send user back to home institution for more information and/or access to content • Future • Metadata enrichment • Resource licensing • … Getty Technical Talk
Why share metadata? • Benefits to users • One-stop searching • Aggregation of subject-specific resources • Benefits to institutions • Increased exposure for collections • Broader user base • Bringing together of distributed collections Don’t expect users will know about your collection and remember to visit it. Getty Technical Talk
Why share metadata with OAI-PMH? • “Low barrier” protocol • Shares metadata only, not content, simplifying rights issues • Same effort on your part to share with one or a hundred service providers (basically) • Wide adoption in the cultural heritage sector • Quickly eclipsed methods such as Z39.50 Getty Technical Talk
Sharing can be hard • Some initiatives have fizzled out • CIMI • AMICO • Some are still going • ARTstor • RLG Cultural Materials • CAMIO and other AMICO derivatives • Art museums have been most active • Customizing for each individual aggregator isn’t sustainable Getty Technical Talk
Sharing is easier with OAI-PMH • Framework for sharing with multiple aggregators • Museum-centric OAI initiatives are emerging • CDWA Lite from the Getty • RLG Museum Collections Sharing Working Group • Museums are beginning to explore more open sharing models Getty Technical Talk
Challenges to OAI-PMH adoption for museums • Protocol implicitly assumes you want metadata to be harvestable by anyone • DC a poor match for describing most museum materials • Museums often want to share content as well as metadata (with select partners) One solution? Start a specialized service provider in the community. Getty Technical Talk
Some service providers • OAIster • National Science Digital Library • Sheet Music Consortium • Open Language Archives Community Getty Technical Talk
“Shareable” metadata • Promotes search interoperability - “the ability to perform a search over diverse sets of metadata records and obtain meaningful results” (Priscilla Caplan) • Is human understandable outside of its local context • Is useful outside of its local context • Preferably is machine processable Getty Technical Talk
Models for sharing with OAI-PMH Digital asset management system QDC MODS Metadata creation module OAI data provider module Transformation DC CDWA Lite Metadata creation module Static Repository Gateway OAI Harvester Transformation XML File QDC MODS Metadata creation system Stand-alone OAI data provider Transformation DC CDWA Lite Getty Technical Talk
Basic metadata sharing workflow • Create metadata, thinking about shareability • Determine format(s) you wish to share your metadata in • Transform records into versions appropriate for sharing via OAI • Validate transformed metadata • Load transformed metadata into OAI data provider • Test with OAI Repository Explorer • Communicate with service providers • See what your metadata looks like once a service provider harvests it Getty Technical Talk
Expanding the scope • “Over time, however, the work of OAI has expanded to promote broad access to digital resources for eScholarship, eLearning, and eScience” • Some experiments with sharing content • CIC Metadata Portal • Fedora Asset Actions • MPEG-21 DIDL over OAI-PMH • OAI-ORE Getty Technical Talk
CIC Metadata Portal • Research project to build an OAI-based aggregator for a consortium of academic libraries in the Midwest • Created a version of qualified DC to indicate the location of a thumbnail image • Integrated harvested thumbnails into search interface • Procedure documented in January 2006 D-Lib Magazinearticle Getty Technical Talk
Asset Actions • Grew out of need for “actionable URLs” • XML schema designed for facilitating the sharing and manipulation of digital objects • Define core functions for digital objects of all types, e.g., “get preview” • Begun to define further functions for specific content types • Proof-of-concept implementation created for DLF Aquifer project • Can be shared via OAI-PMH as a supplemental metadata format • Documented in October 2006 D-Lib Magazine article Getty Technical Talk
MPEG-21 DIDL over OAI-PMH • Repository architecture at Los Alamos National Laboratory uses MPEG-21 DIDL for complex digital objects • OAI-PMH repositories integral parts of the internal repository architecture • These internal OAI-PMH repositories do not support DC metadata – “Because mapping a DID that represents a complex digital object to simple DC is quite an impossible task, support of DC by these OAI-PMH repositories is rather meaningless.” • Described in 2004 JCDL paper • Lay the groundwork for OAI-ORE Getty Technical Talk
OAI-ORE • Open Archives Initiative Object Re-Use and Exchange • Two-year Mellon-funded project beginning October 2006 • Will develop specifications that allow distributed repositories to exchange information about their constituent digital objects • Goal is to facilitate “a new digitally-based scholarly communication framework” • Imagine how research could be transformed if users had seamless access to information in any repository, anywhere, and the tools to use them Getty Technical Talk
Goals for initial OAI-ORE project • Formation of an international advisory committee, consisting of leaders in e-Science, institutional repositories, publishing, library, and educational technology communities. • Formation of an international working group that will meet over the two year period and develop the set of ORE specifications. • Establishment and management of an experimental deployment community that will exercise the developed standards in a variety of contexts. • Establishment of a sustainable community to support the widespread deployment and management of the standards fabric. Getty Technical Talk
OAI-ORE potential for cultural materials • Original focus is on scholarship, and sharing text and datasets • No inherent limitations to these uses • Facilitates, but doesn’t require exchange of actual content • Focus on complex objects better suited to cultural materials than OAI-PMH model • It’s still early, but inherent flexibility of model looks promising for cultural materials Getty Technical Talk
For more information • jenlrile@indiana.edu • These presentation slides <http://www.dlib.indiana.edu/~jenlrile/presentations/getty2007/oai.ppt> • OAI home page<http://www.openarchives.org> • OAI-PMH <http://www.openarchives.org/pmh/> • OAI-ORE <http://www.openarchives.org/ore/> Getty Technical Talk