1. Chapter Eight Interoperability How to Build a Digital Library
Ian H. Witten and David Bainbridge

2. Interoperability
Cooperating to provide a universal information service
Standards
Documents
Metadata
Queries
Protocols

3. Names URL – Uniform Resource Locator PURL – Persistent URL
URN – Universal Resource Name
URI – Uniform Resource Identifier

4. URL Type of URI Useless if resource identifier is unavailable
Informal term, no longer used in technical specifications
Associated with popular URI schemes:
ftp
http
mailto

5. PURL
Organizational commitment to availability over an extended period of time
OCLC

6. URN
Type of URI
Includes a naming authority that is able to resolve the URN and provide the named info
Intended to serve as a persistent, location-independent resource

7. URI
Generic set of all names or addresses that are short strings referring to resources

8. Namespaces
Help avoid confusion with XML tags that are designed for different purposes
Can be used for:
XML Documents
DTDs
XSL Stylesheets
Namespace Example:
xmlns:xsl =
xmlns:fo =
Note: xmlns – qualifier that sets up a namespace

9. Links
Xpointer – a development of Xpath that provides a finer degree of control over part(s) of the document selected
Xlink – general way of connecting selected resources
Together these provide the foundation for bi-directional links, multi-way links, and annotated links

10. Links (cont.) Some XLink attributes: Type Href Actuate Show
Simple, Extended, Arc, Locator , Resource, Title
Href
Indicates the resource that the link addresses
Actuate
Determines when destination resource is accessed
onRequest, onLoad
Show
Determines where destination resource is displayed
replace, new, embed

11. Types XML Schema has extensive facilities for data typing String
Boolean
Numeric
Time

12. Resource Description
Resource Description Framework (RDF) – designed to facilitate the interoperability of metadata.
A way of modeling anything that can be represented as a URI
Resources described in a compositional framework
Serialization via XML

13. Collection Level Metadata
Structured info about the entire collection
Coverage
Number of documents
Access conditions
Collection Understanding
Coming to an understanding of the contents of a collection by inspecting individual artifacts, metadata filtering and interactive information visualization

14. Open eBook
Open eBook Forum – association of hardware and software companies, publishers, authors, users, and related organizations whose goal is to establish common specifications for eBook systems that will benefit content creators, manufactures, and consumers
Open eBook uses XML namespaces, document type definitions, cascading style sheets, subset of HTML 4.0/XHTML, Dublin Core, Unicode and a set of MIME types

15. Open eBook (cont.)
Each publication takes the form of a package file with extension .opf
Unique publication identity
Metadata
Manifest list of supporting files
Spine – linear reading order for files
Tours – permit different traversal patterns through material
Guide – structural elements, such as a title page or table of contents

16. Query Language Common Command Language (CCL) (Z39.58)
Defines an information retrieval cycle that is independent of the software used
Contains commands
Starting a session
Choosing collections
Finding items in collections
Sorting results
Displaying items
Printing items
Reviewing previous queries
Stopping a session

17. XML Query
Xquery
Queries are used to construct new XML documents from existing XML document collections
Build upon XPath and XML Schema
Contains its own functional programming language
Data model
Forests of trees

18. Protocols
Z39.50
OAI
Dienst
SDLIP