OAI from 50,000 Feet

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OAI from 50,000 Feet

• OAI develops and promotes interoperability
  solutions that aim to facilitate the efficient
  dissemination of content.
• Begun in 1999 to encourage the development of
  e-print solutions
• Archive Repository
• Open means facilitating the availability of
  content from many different providers does not
  mean free or unlimited

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OAI from 50,000 Feet

• OAIs technological framework and standards are
  independent of content offered and the economic
  mechanisms surrounding that content
• Technical framework provides low barrier for
  interoperability
• Data providers adopt the OAI technical framework
  as a means of exposing metadata
• Service providers harvest metadata from data
  providers using the OAI protocol and use the
  metadata fro value-added services
• OAI metadata uses unqualified Dublin Core, and
  all fields are optional

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OAI and UT

• Open Archives Initiative (OAI) -
  http//www.openarchives.org/
• Joint effort between DLF and Mellon Foundation
• Documents, tools, community listservs, latest OAI
  news and updates.
• Data Providers and Service Providers Harvesting
  Protocol
• Data Server (has data and waits for someone to
  come get it)
• Service Client (sends a request to data
  provider) Old Dominion
• Mellon grants of approx. 1.5M for service
  providers
• University of Tennessee
• UT Library was a founding member of the (DLF) -
  http//www.diglib.org
• UT is a Data Provider for OAI.
• UT currently uses OAI with TEI, EAD, JPEG, PDF,
  RM, and other formats. OAI Records on UTK
  Sunsite. Digital Objects on other servers.

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OAI Records - General

• Each OAI Record and the repository must be
  compliant with the protocol however,
• OAI Protocol not concerned with policies of
  individual archives
• No implications for physical storage, cost of
  data, or access control to server.
• No specifications for metadata and data formats

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OAI Records - Continued

• A record is a piece of XML that stores metadata.
• XML schema specifies the structure. Very precise.
• Each record must be uniquely addressable.
• Each metadata entity must be persistent
• Metadata must be persistent.
• Object can change or cease to exist.
• If metadata is persistent the record can always
  be found but you dont have to keep the object
  forever.

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OAI Records - Continued

• Each record contains three parts
• Mandatory Header
• Contains unique identifier (oaiutkvid/vid0001)
• Data stamp (update as record is changed)
• General and Options Metadata
• Mandatory - oai_dc (unqualified dublin core)
• Optional - EAD, MARC, RDF, CIMI, TEI, etc.
• Optional About
• a. About the metadata (metadata is about the
  data)

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Unqualified Dublin Core and OAI

• 15 Dublin Core Elements
• All are optional All are repeatable
• Sets Optional
• Nothing to do with OAI protocol
• Everything to do with the archive

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Unqualified Dublin Core - OAI_DC
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OAI Record for Video
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OAI Repository Explorer

• Enforces interoperability by testing quality of
  metadata
• Tests interfaces
• Simulates use of an archive (repository) by a
  typical service provider
• Allows browsing of an archives contents using
  only the OAI protocol.
• Checks syntax and encoding of data.

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OAI Repository Explorer 1.1
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OPTIONS FOR SHARING METADATA
SOAP - Simple Object Access Protocol Version
1.1 W3C Note 08 May 2000 Simple and lightweight
mechanism for exchanging structured and typed
information between peers in a decentralized,
distributed environment using XML. 3 Parts
SOAP Envelope, SOAP encolding rules and SOAP RPC
(remote procedure calls and responses). http//www
.w3.org/TR/SOAP/_Toc478383486
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SOAP fundamentally one-way
transmissions from a sender to a receiver but
SOAP messages may be combined to implement
patterns such as request/response. Headers can
contain information or applications to be used by
intermediate destinations. The body contains the
information for the ultimate destination. One way
initiation. Not intended for bulk data mining
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Z39.50 Information Retrieval Application Service
Definition and Protocol Specification Granular -
Can search by any query attribute, including
format (problems--multiple formats, inconsistent
use for moving images) Also a profile for
holdings, to identify multiple copies of an
object. Would need extension for bulk
mining. http//www.loc.gov/z3950/agency
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DESIGNING METADATA TO SUPPORT OAI
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DESIGNING METADATA TO SUPPORT OAI
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DESIGNING METADATA TO SUPPORT OAI
Response record returned for deleted metadata
record
ltidentifiergthttp//www.anyarchive.org/delrec.html
lt/identifiergt lttitlegt This title is no longer
available lt/titlegt ltdate.deletedgt
2001-18-15lt/date.deletedgt ltdescriptiongt Please
contact the archive reference department for
assistance in locating an alternative resource
reference_at_anyarchive.orglt/descriptiongt