European Endeavor Users Group MeetingHelsinki, Sept 1-6 2003Esa-Pekka Keskitalo, System AnalystHelsinki University Library

OpenURL 1.0

Outline

• Background• The Draft• OpenURL in Libraries

Background

• Appropriate Copy Problem• Broken Link Problem

• Appropriate Copy – Linkking should be user sensitive

• Broken Links should be fixed centrally (need to be fixed somewhere)

OpenURL is

”a methodology for describing • resources that that are referenced in

a networked environment • context of the reference”• Neutrally in respect to applications

and user communities

From 0.1 to 1.0

• Much extended• ”Registry”• From ”scholarly” to a more general

approach

Standard in two parts

1. ContextObjecta) A description of a resource

that is referenced (target)b) A description of the context

of the reference (source)c) A definition of a set of Namespaces

2. Registrya) Detailed lists of options – will expand

A Context Object is a Set of Entities

• Context Object is an information construct with six Entities.

• Referent is the core entity sine qua non

• Referent = what is being referenced= what we e.g. want to read in fulltext

ContextObject

Entities

Resolver

Referent

Referrer

Service type

RequesterReferring Entity

ContextObject

Entities

1. Referent: a referenced resource, e.g. an article, a person etc.

2. Referring entity: where the reference is, e.g. an article

3. Requester: who is using the system4. Service Type: what is wanted, e.g.

”fulltext”5. Resolver: the target resolving service6. Referrer: The system that generates the

ContextObject.

ContextObjectEntities

Descriptors

Detailed information about an Entity.1. Identifiers2. Metadata-by-Value3. Metadata-by-Reference4. Private Data

ContextObjectEntitiesDescriptors 1) Identifiers

Defines1. Namespace that is being used2. Identifier, unique in that Namespace

Namespace: DOIIdentifier: 10.1126/science.275.5304.1320

Namespace: MailtoIdentifier: some.one@helsinki.fi

Namespace: ISSNIdentifier: 1234-5678

ContextObjectEntitiesDescriptors 2) By-Value Metadata

Defines• the metadata format used• metadata expressed in that format

Metadata: MARC21 = MARCXML Schemarft_val_fmt = ori:fmt:xml:xsd:MARC21

<?xml version=”1.0” encoding=”UTF-8”?>---<varfield id="245" i1="1" i2="0"> <subfield label="a">Policing the new world disorder /</subfield> <subfield label="c">by Robert Oakley and Michael Dziedzic. </subfield> </varfield>

ContextObjectEntitiesDescriptors 3) By-Reference-Metadata

Defines• the Metadata Format used• the network location of the metadata

Metadata: MARC21 = MARCXML Schema

rft_ref_fmt = http://www.loc.gov/standards/marcxml/schema/MARC21slim.xsd

rft_ref = http://www.loc.gov/standards/marcxml/Sandburg/sandburg.xml

ContextObjectEntitiesDescriptors 4) Private Data

• Not defined in the Standard• Specific to the Referrer (the generator

of the ContextObject)• Must be understood by the Resolver

ContextObjectEntities Constraints

• Exactly 1 Referent in one ContextObject• No more than 1 Referring Entity,

Requester, Referrer• Zero or more Service Types and

Resolvers.

• All Descriptors may describe all Entities• Multiple Descriptors possible

REGISTRY

• description of network-referenced resources

• description of the context of the references

• support of transportation of the descriptions over the network

Registry

Components

1. Namespaces– 3 Naming Environments

2. Character Encodings3. Physical Representations4. Constraint Languages5. Context Object Formats6. Metadata Formats7. Transports8. Community Profiles

Registry Components

1) Naming Environments

a) URI – Uniform Resource Identifierb) ORI – Open Resource Identifierc) XRI – Private Resource Identifier

Registry Components Naming Environments

a) Uniform Resource Identifier

– Internet Assigned Naming Authority (IANA)

– http, ftp, mailto– ldap– urn, urn:ISBN, urn:ISSN, urn:NBN

Registry Components Naming Environments

b) Open Resource Identifier

• bibcode, doi, isbn, issn, oai, sici• Id for Referrers:

– domain name + string

• Id for Service Types: – abstract, citation, fulltext, holdings, ILL

Registry Components Naming Environments

c) Private Resource Identifier

• Not defined any further

Registry Components

2) Encodings

• Character Encodings– UTF-8, ISO-8859-1, Big5– IANA List

Registry Components 3) Physical Representations

• Physical Representations– XML and KEV (Key/Encoded Value)– KEV specified in the Standard

Registry Components 4) Constraint Languages

• Constraint Languages– Z39.88-2003 MTX– W3C XML Schema

Registry Components

5) Context Object Formats

• Format– a concrete method to express a class of

information constructs– Physical representation + constraint language+

constraints

• A definite choice set within the Format triple– KEV + MTX + Matrix of Section 8.1. of Part 2– XML + XSD + XML Schema of Section 8.2 of Part

2

Registry Components

6) Metadata Formats

• MARC 21• OAI_dc• XML and KEV metadata formats for

books, dissertations, journals, patents specially defined

Registry Components

7) Transports

• Method of tarnsporting over the network• OpenURL 0.1 for backwards compatibility• 6 combinations: OpenURL http or https

– inline– by reference GET / POST– by value GET / POST

Registry Components

8) Community Profiles

• A set of choices from Registry entries for an application domain– 1 Context Object Format– Metadata Formats– URI and ORI Namespaces– Transports– Identifiers– Expressed in XML

Draft Standard 1.0

• Released in March• Time for testing and comments ends

in November, 2003• Big changes to version 0.1

OpenURL resolving server

• Resolving server needs constat attention

• Centralised update services emerging, but -

• Central knowledge needs adjusting• Local knowledge needed in addition • Growing demand for reliable identifiers• A standard for knowledge database

format would be useful

Library Systems

• Need to be ”OpenURL Enabled”• 0.1 ”pretty easy”; how about 1.0?

OpenURL and cataloguing

• What should be catalogued into the records?

• Every static URL in records will be a problem

• Static URLs still useful as long as they work

• Cataloguing rules revision?

OpenURL and the others

• DOI and URN are for persistent linking, OpenURL for context-sensitive linking Work well togethet

• OpenURL is not a new Z39.50. With OpenURL, you have to know what you are looking for.

• OpenURLs are not for human eyes

OpenURL in the Future

• OpenURL is gaining momentum

• Standardisation• Sharing of knowledge• Identification• Software development