SCORM-NSDL Workshop May 18, 2004

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Educational Materials are Scattered across the Internet

NASA

Math ForumState standards

Scientific American

Ask a Scientist

GROW

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... to provide a coherent set of collections and services across

great diversity

The Integration Task ...

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Interoperability

The Problem

Conventional approaches require partners to support agreements (technical, content, and business)

But NSDL needs thousands of very different partners

... most of whom are not directly part of the NSDL program

The challenge is to create incentives for independent digital libraries to adopt agreements

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Standards: Function Versus Cost of Acceptance

Function

Cost of acceptance

Many adopters

Few adopters

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Example: Textual Mark-up

Function

Cost of acceptance

SGML

ASCII

HTML

XML

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Standardization in the NSDL

Coax and cajole, not regulate

• Diverse communities with different standardization needs and traditions

• Low incentives to conform to imposed standards

• Mixed expertise when attempting to conform

Yet, surprisingly many organizations will voluntarily follow clear guidelines

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The Spectrum of Interoperability

Level Agreements Example

Federation Strict use of standards AACR, MARC(syntax, semantic, Z 39.50and business)

Harvesting Digital libraries expose Open Archivesmetadata; simple metadata harvesting

protocol and registry

Gathering Digital libraries do not Web crawlerscooperate; services must and search enginesseek out information

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The Repository holds information about every collection and item known to the NSDL.

The NSDL Repository

NSDL Repository

redistribute

ingest

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Standards Implemented in the NSDL Repository Phase 1Object model

Metadata: Dublin Core with educational extensions

Ingest and redistribution: Open Archives Initiative, Protocol for Metadata Harvesting

item metadata

collection metadata

URL

URLItems

Collection

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NSDL Search Service

Search Service

Collections

NSDL Repository

The search service has been built by the University of Massachusetts, Amherst

http

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NSDL and the Web

Collections

NSDL Repository

http

http

http

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NSDL Archive and Preservation Service

Collections

NSDL Repository

The archive service has been built by the San Diego Supercomputing Center

ArchiveArchive Service

http

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NSDL Community Input

Recommendationsand Reviews

Collections

NSDL Repository

http

?

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NSDL Repository: Recent Decisions

Object model and options for redistribution

• Content and metadata management (Fedora model)

• Relationships between objects (RDF)

• Web Services (WSDL)

• Publish/subscribe

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NSDL Repository: Discussion Items

Federation(s)

• Should we support selected federations (e.g., SCORM)?

Object model

• Should we support selected packaging standards (e.g., METS, IMS, MPEG-21)?

• Should we support a persistent identifier system other than URLs and OAI identifiers (e.g., Handle, DOI)?

Persistence

• How can our technical decisions enhance persistence and reuse?

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