The Fedora Project April 28-29, 2003 CNI, Washington DC

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The Fedora Project April 28-29, 2003CNI,
Washington DC

• Thornton Staples
• University of Virginia

Sandy Payette Cornell Information Science
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Priorities for digital libraries

• Managing digital resources as if they are all the
  same
• Delivering digital resources as if they are all
  unique and free to participate in any number of
  contexts
• Supporting digital scholarship wherever it may
  lead

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Shortcomings of commercial digital library
products

• Narrow focus on specific media formats (e.g.
  image databases, document management)
• Fail to effectively address interrelationships
  among digital entities
• Fail to address interoperability.
• Fail to provide facilities for managing programs
  and tools that deliver digital content.
• Not extensible do not enable easy integration of
  new tools and services

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The Flexible Extensible Digital Object Repository
Architecture (FEDORA)

• Developed as a DARPA and NSF-funded research
  project at Cornell (1997-present)
• Interpreted and re-implemented at University of
  Virginia (1999)
• Virginia prototype supported a testbed of
  10,000,000 digital objects with very good results
  (1999-2001)
• Andrew W. Mellon Foundation granted Virginia and
  Cornell 1,000,000 to develop a full-featured
  production FEDORA system that is web-based (2002)

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Users access data objects through behaviors.

• Dynamic
• data

Application
services
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Managers have direct access to each component of
a data object.
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The Current Project

• An efficient, scalable, freely distributable
  FEDORA repository system ASAP
• A complete basic management interface with the
  initial release
• Add important digital library functionality in
  later releases
• Multiple testbed repositories to deploy and
  evaluate the software
• Make all software open source

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Deployment Partners

• Indiana University Digital Library group
• Kings College London Humanities Computing
• Library of Congress Motion Picture and Recorded
  Sound Division
• Los Alamos National Laboratory Research Library
• New York University Humanities Computing
• Northwestern University Academic Computing
• Oxford The Refugee Studies Center
• Tufts Digital Collections and Archives

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Fedora 1.0

• Architecture
• Software
• Release 1.0 Features
• Demo Use Cases

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Digital Object Model Architectural View
Globally unique persistent id
Persistent ID (
PID
)
Public view access methods for obtaining
disseminations of digital object content
Disseminators
Internal view metadata necessary to manage the
object
System
Metadata
Datastreams
Protected view content that makes up the
basis of the object
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Digital Object Model Example Disseminators

• Get Profile
• List Items
• Get Item
• List Methods
• Get DC Record

Persistent ID (
PID
)
Disseminators
Default
Simple Image

• Get Thumbnail
• Get Medium
• Get High
• Get VeryHigh

System
Metadata
Datastreams
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Object Behavior Contracts
Behavior Definition Object
behavior subscription
Data Object
behavior contract
data contract
Web Service
Behavior Mechanism Object
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Basic Repository Architecture

• Repository System
• Object Management
• Lifecycle (Ingest/create ? Store ? Delete ?
  Approve ? Purge)
• Validation
• PID Generation
• Version management
• Access Control
• Preservation support
• Object Access
• Object Dissemination
• Object Reflection
• Service Mediation

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Fedora and Web Services

• Fedora Repository system is a web service
• Access/Search (API-A) and Management (API-M)
• Service descriptions published using WSDL
• Both SOAP and HTTP bindings
• Back-end services
• Digital object behaviors implemented as linkages
  to other distributed web services
• Service binding metadata (WSDL) stored in special
  Fedora Behavior Mechanism objects.
• Fedora acts as mediator to these services.

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Fedora Repository SystemClient and Web Service
Interactions
Backend
Frontend
Fedora Repository System
Content Transform Service
client application
client application
user
Service
Web Service
Web Service Dispatch
Content Transform Service
web browser
user
Service
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Fedora Repository System
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Server Design 3 Layers
Interface Service Exposure Access API (API-A, API-A-LITE) Management API (API-M)
Application Logic Implements management, access, and security in terms of the Fedora object model.
Storage Database and File system XML object serializations cache(s).
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Fedora 1.0 Features

• Public APIs - exposed as web services
• Flexible Digital Object Model
• XML submission and storage (extension of METS
  Schema)
• Local and distributed content
• Data (any type) and metadata (any schema DC,
  other)
• Supports inter-relationships among objects
• Behavior contracts for objects
• Associate services with objects
• Objects can provide launch-pad or tool to use
  object content
• Repository System
• Management Service - manage digital resources,
  metadata, as well as computer programs, services
  and tools that support them
• Access Service repository search and object
  disseminations
• Mediation - interactions with other distributed
  web services for content transformation and
  presentation
• Admin GUI client object creation, update,
  purge, search
• OAI-PMH Provider provides OAI-DC
• Basic Access Control - IP-based

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Fedora 1.0 (available May 16, 2003)

• Open Source Software
• GNU General Public License (GPL)
• Implementation Technologies
• Sun Java J2SDK1.4
• Apache Tomcat 4.1 and Apache Axis (SOAP)
• Xerces 2-2.0.2 for XML parsing and validation
• Saxon 6.5 for XSLT transformation
• Schematron 1.5 for validation
• MySQL-2.23.52 and Mckoi relational database
• Deployment Platforms
• Windows 2000, NT, XP
• Solaris
• Linux

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DEMO Basic Use Cases

• Connect to Repository

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Finding Aids Collections at Virignia
Connect to Repository
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Fedora Future Development Plans
1 Year Out
2-3 Years Out

• Integrity Management Tools
• Service liveness checker
• Link liveness checker
• Logging and stats
• Object Versioning (for behaviors)
• R2R Federation
• Shared PID resolver service
• Interoperability features
• Performance
• Repository clustering
• Load balancing
• Reliability
• Fault Tolerance
• Mirroring and Replication
• Backend Service Mediation
• SOAP dispatcher

• Full API-M implementation
• Advanced Access Control
• Shibboleth
• XML Policy expression
• Fine-grained enforce
• Object Versioning (for content)
• More object creation tools
• Improved Searching
• Performance
• Tuning
• Caching

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Questions

• www.fedora.info