Interoperability:The Digital

Library Holy Grail

Roy Tennant

escholarship.cdlib.org/rtennant/presentations/ala2000/exlibris/

An Assumption & an Acknowledgement

• You have a passing familiarity with common digital library terms

• I stole some of the following from Paul Miller, Interoperability Focus, UKOLN, see http://www.ariadne.ac.uk/issue24/interoperability/

Why Interoperability?A Brief Look at 3 Digital Library

Projects

Why Interoperability?:The Vision

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Why Interoperability?

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Why Interoperability?

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Why Interoperability?

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http://searchlight.cdlib.org/

Facets of Interoperability

• Technical

• Semantic

• Political/Human

• Inter-Community

• International

Technical Interoperability

• The ability of technical systems to interoperate

• Standards are needed in at least these areas:– Communication (e.g., TCP/IP)– Transport (e.g., HTTP)– Representation (e.g., XML)– Linking (e.g., SFX)

Semantic Interoperability• Agreement on meaning• The problem:

– Using different labels for the same thing (e.g., author, creator, composer)

– Using the same label to describe different things (e.g., date)

• Possible solutions:– Thesauri and vocabularies (with crosswalks)– Standardization of terminology

See http://www.ariadne.ac.uk/issue23/metadata/ for more info

Political/Human Interoperability

• Making resources widely available has impacts on people and organizations

• Possible difficulties of differing goals, clienteles with varying needs, need for staff training, etc.

• Will require a high degree of communication, cooperation, and political will

Inter-Community Interoperability• Ability of differing communities to interoperate• Libraries, museums and archives are a prime

example• Possible difficulties include divergent perspectives

on item description, different terminologies, different needs

• Strategies for success may include focusing on common problems and providing for customization

International Interoperability• All of the issues above, but across political, temporal,

and geographic barriers

• Difficulties include differences in professional practices enshrined in age-old precedent, language and script issues, varying degrees of subsidy and support, etc.

• Mundane but frustrating barriers:– Time zone differences– Differences in communication styles– Our unwillingness to accept international standards

Example Interoperability Initiatives

• NSF-Funded cooperative digital library project: UCSB, UCB, Stanford, CDL, and SDSC, see http://www.npaci.edu/Thrusts/DI/libraries.html/

• UK Interoperability Focus, see http://www.ukoln.ac.uk/interop-focus/

• Virtual Canadian Union Catalogue, see http://www.nlc-bnc.ca/resource/vcuc/

• ONE - OPAC Network in Europe, see http://www.dbc.dk/ONE/oneweb/

Methods of Achieving It

• All use the same systems and infrastructure

Not bloody likely!

• Create a massive union catalog of resources

Hmm….kinda sounds like OCLC...

• All adhere to the same protocols, standards, and guidelines

Hey — now you’re talking!

Methods of Achieving It: Standards

• MARC (with AACR2)• Z39.50 (w/ Bib-1, Bath Profile, etc.)• XML (w/TEIlite DTD, etc.)• Dublin Core• SFX, OpCit, CrossRef• Simple Digital Library Interoperability Protocol

(SDLIP)?• And more...

Methods of Achieving It: Guidelines & Best Practices

• Guidelines and best practices can help where standards don’t exist or are inappropriate

• Some areas in which best practices are now available:– Metadata capture and recording– Imaging

Methods of Achieving It: Strategies• Develop standards, guidelines, and best practices

(cooperatively as much as possible)

• Establish formal linkages between existing organizations and projects

• Create cooperative development projects (I’ll see your programmer and raise you a project manager…)

• Broadly share your ideas and technologies

• Require vendors to support key standards as a condition of sale

Why Will it Never be Fully Achieved?

• Market forces

• The pace of change

• Complexity of systems and diversity of data, metadata, terminologies, etc.

• Organizational, political, and cultural realities

But is it Worth the Quest?

Certainly! Our users deserve no less.Godspeed!