Active Digital Object Repository Architecture

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Active Digital Object Repository Architecture

• Jason Petrone
• jpetrone_at_cnri.reston.va.us
• Corporation for National Research Initiatives

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Classic Repository Architecture

• Server Provides
• Connectivity
• Functionality
• Authentication
• Authorization

User Interface (WWW Browser, Custom Application)
Server (WWW Server, Custom Programs)
Storage (Legacy, Database, File System)
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Classic Repository Architecture

• Server Provides
• Connectivity
• Functionality
• Authentication
• Authorization

User Interface (WWW Browser, Custom Application)
Server (WWW Server, Custom Programs)

• Problems
• Interoperability
• Metadata
• Persistent Identifiers
• Resources

Storage (Legacy, Database, File System)
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ADORA Repository Architecture

• Server Provides
• Connectivity
• Functionality
• Authentication
• Authorization

User Interface (WWW Browser, Custom Application)
ADORA

• Problems
• Interoperability
• Metadata
• Persistent Identifiers
• Resources

Storage (Legacy, Database, File System)
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Digital Infrastructure Types

• How content is represented within the repository
• Describes a medium
• Sets requirements for input data
• Specifies interactive behaviors
• Get GIF Page - takes a page number as an
  argument
• Count Words
• Get PDF
• Get Metadata Field - takes the name of a field
  as an argument

• Content (SGML)
• Metadata(ISO11179)

Abstract Book

• Single page in GIF Format
• Word Count
• Entire Document in PDF Format
• ISO11179 Metadata Field

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Digital Infrastructure Object

• Implements a type
• Created using input data in formats specified by
  type
• Automatically gains all functionality from the
  type
• Portable
• All data and metadata components encapsulated
• Contains references to programs necessary for
  processing
• Handle is a unique identifier that is easily
  modified to point at a different location, or
  many different locations

• mtwain1880.sgml
• mtwain1880.xml

The Innocents Abroad by Mark Twain
cnri.adora/mtwain/book1880

• Single page in GIF Format
• 153451 Words
• Entire Document in PDF Format
• ISO11179 Metadata Field

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Benefits

• Interoperability
• Designed with scalability in mind
• Facilitates creation of new complex types
• Provides features often built from scratch
• Cataloging / Searching
• Caching / Mirroring
• Security