Introduction to Linking Technologies & OpenURL

1. Introduction to Linking Technologies & OpenURL Lori Jean Ostapowicz Critz Georgia Institute of Technology 5/20/04

2. Linking Technology • Permits context-sensitive linking between various web-based resources • Allows libraries to combine electronic resources (full-text journals, abstracting & indexing databases, citation databases, online library catalogs, interlibrary loan/document delivery systems, search engines) to function as a cohesive, one-stop reference system

3. OpenURL Framework • Provides a means of DESCRIBING a reference resource along with a description of the CONTEXT of the reference • Also defines methods of TRANSPORTING these descriptions between networked systems • Used to REQUESTSERVICES pertaining to the referenced resources that are appropriate for the requestor (i.e. enables context-sensitive linking from a reference in a scholarly system to resources relevant to the reference)

4. OpenURL Framework • A user clicks a link or a button in an HTML page (usually in an abstracting & indexing database or in a reference list of an electronic journal article) • As a result of activating the link or button, a description of the scholarly resource (such as a journal article) is transported (e.g. via HTTP(S) GET or POST) to a LINKING SERVER along with information about the dynamic context of the reference • This dynamic context enables a list of relevant services, appropriate to the user, to be provided • The LINKING SERVER and its RESOLVER SOFTWARE processes the description/information to provide this list of options/services (full-text; print holdings ; interlibrary loan, …)

5. How Does the System Work? Begins with SOURCES that can send an OpenURL to the Linking System/server (Where the user begins the search!) A & I Databases OPAC Publisher sites Aggregated Databases OpenURL OpenURL OpenURL OpenURL The System evaluates the ‘request’ and looks for options that can be provided for the desired item. OpenURL-enabled Library Linking System Subscription Agents Aggregated Databases PUBLISHER SITES Ends at TARGETS that lead to the desired item or presents alternatives for finding it. (Where the user lands!) OPAC INTERLIBRARY LOAN

6. Link resolvers manage the linking process … ISI Ingenta Publisher sites The Resolver can link to the resources. Information sources need only to know how to link to a link resolver. Resolver is usually controlled by the library. The Resolver is the one place that manages holdings and links. Link Resolver Full text DBs More Publisher sites Library A&I service Google Adapted from Oliver Pesch Chief Architect, EBSCO Publishing

7. Without a link resolver the user may notaccess the appropriate (i.e. ‘free’ full-text) copy ISI Pay per view $$$ Ingenta A Publisher sites Library subscribes Full text DBs Other Publisher site A With a predefined link, the user may be presented with a link and not have a choice where that link goes Library A&I service Google User Adapted from Oliver Pesch Chief Architect, EBSCO Publishing

8. With a link resolver, the library candetermine which copy is appropriate ISI Pay per view $$$ Ingenta A Publisher sites  Link Resolver Library subscribes Full text DBs Other Publisher sites A With the resolver, the library can control where the link goes and get the user to the appropriate copy. As long as the A&I service knows the user/library has a resolver and where it is, it can create the link. Library A&I service Google User Adapted from Oliver Pesch Chief Architect, EBSCO Publishing

9. Components of Linking System • OpenURL- enabled Content Providers • Called SOURCES or REFERRANTS or REFERRING SOURCES • Generate the OpenURL to start the process • Can also serve as targets (e.g. Proquest) if linked TO by link resolver/server • Data about the Collection • Inaccurate data leads to linking errors, incomplete holdings information, and inaccurate availability statements • Resolver • Performs the comparison between the collection /holdings and the desired cited item • Displays options/results (e.g. links to full-text or OPAC) and additional features (e.g. links to ILL/document delivery, Google search, Endnote connection)

10. Linking Technology in Action …

11. A search in CSA Sociological Abstracts (the SOURCE) leads a user to a citation for a desired item …

12. The citation is described, in part, by the following metadata: Article Title: Cultural Values and Happiness: An East-West Dialogue Journal: Journal of Social Psychology ISSN: 0022-4545 Author: Lu, Luo; Gilmour, Robin; Kao, Shu-Fang Start Page: 477 Volume: 141 Issue:4 Date: Aug. 2001

13. When the user clicks on the link resolver logo or link (SFX in this case), the OpenURL carries the metadata about the article to the link resolver.

14. The OpenURL that describes the citation would look something like this: http://VD2YN4ULBU.linkresolver.com/?atitle=Cultural+Values+and+Happiness%3A++An+East-West+Dialogue&volume=141&issue=4&date=2001&spage=477&aulast=Lu&aufirst=Luo&issn=0022-4545&title=The+Journal+of+social+psychology The OpenURL ‘organizes’ the metadata …… The domain section (BASEURL) of the URL points to the Link Resolver/server (e.g. SFX) that will process the OpenURL. Typically, each library has one link resolver to which all their OpenURLs point. The QUERY section contains the metadata and values for the citation.

15. Description/Context Object Description of the referenced item and the ‘context’ of the referencing action … Version control, character encodings, timestamp, etc. Administrative Referent Item being referenced. (e.g. bibliographic reference in full text article) “User” making the request Requester Service creating the link. (e.g. where the user found the reference) Referrer ReferringEntity The item which contains the reference. (e.g. the article in which the bibliographic reference was found) Resolver ServiceType The target of the link - the link server of the user’s institution The desired services from the Resolver. ( Full text, ILL, Abstract, etc.)

16. The Link Resolver compares the data about the item described in the OpenURL with data (knowledge base) about what is held/owned/accessible in the library’s collection The Link Resolver determines if the user has access to this article ---- and, if so, what links it should create for the user. INFORMATION SOURCE OpenURL Resolver

17. The Link Resolver then displays the options/services available to the user (based on the metadata encoded in the OpenURL). SFX Menu of 'options'

18. The user then selects the best option (full-text, link to print holdings record, ILL …) and is presented that option.

19. Full Text The ‘options’ that can be provided vary with the resolver systems used – and are quite diverse! Union Catalog Search Document Delivery Record Downloads Web Search

20. Link Resolvers - Considerations • Must be OpenURL compliant • Should be available as a stand-alone product • Can be a system that is run/managed locally • Local hardware/software with annual maintenance fee • More flexible; more control • Needs to be able to run on several operating systems • OR a subscription service hosted by vendor/provider (ASP Option) • More feasible for those with limited technical staff and hardware • Vendor supplies support in establishing/maintaining system • Hosting site should have 24/7 support and redundant connectivity to Internet • Evaluate ‘match’ of the product’s sources/targets to own collections • Evaluate ‘customization’ options – of both interface (e.g. ranking of results/options obtained) and product itself (e.g. preselected links only or unlimited customization) • Evaluate overall price – varies widely across products In part, from Harry Samuels – Product manager: Endeavor/LinkFinderPlus

21. Link Resolvers - Examples • Standalone Resolvers • SFX (ExLibris) • LinkFinderPlus (Endeavor) • Journal Finder (University of North Carolina – Greensboro) • Gold Rush (CARL) • SirsiResolver (Sirsi) • OL2 (Fretwell-Downing) • 1Cate (Openly Informatics) • ArticleLinker (Serials Solutions) • LinkSource (EBSCO) • Integrated Resolvers • WebBridge (Innovative) • Horizon Link (Dynix) • Resolvers in Proprietary Database Systems • H. W. Wilson • Cambridge Scientific Abstracts

22. OpenURL • First developed by Oren Beit-Arie ( Ex Libris), and Herbert Van de Sompel (Los Alamos National Laboratory) • An accepted “standard” syntax for creating a link between an information source and a link resolver • The means to pre-define/organize sets of metadata elements to use in describing an “item”/resource (e.g. a journal article) • Also includes the ADDRESS of the link resolver • Comprises 2 parts : • BASEURL - identifies the Resolver that will provide the context sensitive services for the OpenURL • QUERY – the DESCRIPTION or metadata attributes and values that make up the citation for the resource/item

23. ANSI Standard: OpenURL .1 to OpenURL 1.0 • More genres supported (e.g. Report, Document, Dissertation, Patentadded) • Richer data formats supported (e.g. Key EncodedValues, XML) • More complete ‘context’ descriptors • More types of transports available (e.g. HTTP Get or Post, ) • More controlled ‘evolution’

24. References • ANSI/NISO Z39.88-2004: The OpenURL Framework for Context-Sensitive Services – The Key/Encoded-Value (KEV) Format Implementation Guidelines - available at http://library.caltech.edu/openurl/StandardDocuments/KEV_Guidelines-20040211.pdf • “The Lure of Linking”. John McDonald & Eric F. Van De Velde. Library Journal (online); 4/1/2004. Available at: http://www.libraryjournal.com/article/CA405398 • “OpenURL and OpenURL Framework: Demystifying Link Resolution - The promise of OpenURL 1.0”. Oliver Pesch. Available at http://library.caltech.edu/openurl/Talks/Oliver%20Pesch%20-%20NISO%20OpenURL%20Workshop-for%20print.ppt • “What is OpenURL?”. Available at http://www.serialssolutions.com/alourl01.asp • “Distributed Systems OpenURL Demonstrator”. Available at http://www.ukoln.ac.uk/distributed-systems/openurl/