OpenURL Link Resolvers 101

Or, what the heck is the difference between:a link resolver,a federated search engine,a full-text aggregator,and a discovery services

platform?

Bill TopritzhoferCoordinator

SWITCH Library Consortiumbtopritz@switchinc.org

Overview

Today's presentation will focus on:

Defining what a link resolver is (and isn't)The ingredients needed to implement a link resolverAn overview of how link resolvers are configured (WebBridge)Consortium considerations

Definitions

OpenURL link resolver

Federated search interface

Full-text aggregator

Discovery services platform

Open URL Link Resolver

Defined by Wikipedia as:

OpenURL is a type of URL that contains resource metadata for use primarily in libraries.

The OpenURL standard is designed to support mediated linking from information resources (sources/targets) to library services (origins/sources). A "link resolver", or "link-server", parses the elements of an OpenURL and provides links to appropriate services as identified by a library. A source is generally a bibliographic citation or bibliographic record used to generate an OpenURL. A target is a resource or service that helps satisfy user's information needs.

Examples include full-text repositories; abstracting, indexing, and citation databases; online library catalogs; and other Web resources and services. OpenURL allows the same information resource to be used at different targets, without needing to customize the link for each target.

Open URL Link Example

An OpenURL consists of a base URL, which addresses the user's institutional link-server, and a query-string, which contains the bibliographic data, typically in the form of key-value pairs. For example:

http://resolver.example.edu/cgi?genre=book&isbn=0836218310&title=The+Far+Side+Gallery+3is a version 0.1 OpenURL describing a book.

2 distinct uses for link resolvers

Database withFull-text of article

Database withcitation only

Link Resolver

Origin/Source Target/Resource

2 distinct uses for link resolvers

Related resources basedon information incatalog record.

(Google, Amazon, IMDB,databases, other catalogs...)

OPAC display

Link Resolver

Origin/Source Target/Resource

Federated SearchDefined by Wikipedia as:

Federated Search is an emerging feature of automated, web based library and information retrieval systems. It is also often referred to as a portal, as opposed to simply a web-based search engine.

Federated searching consists of (1) transforming a query and broadcasting it to a group of disparate databases with the appropriate syntax, (2) merging the results collected from the databases, (3) presenting them in a succinct and unified format with minimal duplication, and (4) providing a means, performed either automatically or by the portal user, to sort the merged result set.

In traditional search engines, such as Google, only sources that have been indexed by the search engine’s crawler technology can be searched, retrieved and accessed. The large volume of documents housed in databases is not open to traditional Internet search engines because of limitations in crawler technology. Federated searching resolves this issue by the technique described above and makes these Deep Web documents searchable without having to visit each database individually.

Diagram

Federated Search Engine

Full-text DB Google Other OPAC Amazon

CUW Central Search example

Full-text aggregatorDefined by Me as:

A full-text aggregator, such as Serials Solutions, provides customers with an interface for identifying their full-text subscription content. With the full-text subscriptions defined the aggregator provides services such as:

A-Z List of electronic full-text holdingsPeriodic updates of holdings (new titles, dropped titles, coverage changes)E-Journal Portal for searchingSubject browsingData file of full-text holdings for use in a link resolverOverlap analysisUsage stats

Additional providers of this service include: Innovative (CASE), EBSCO (A-Z Service), TDNet (Journal Manager), and others.

Serials Solutions Client Center

Discovery services platform (Encore)

Defined by Innovative as:

The Encore discovery services platform brings together library content, community participation, and simple discovery to make the library the preferred destination for finding information.

In other words, Encore is a presentation interface that sits above all your other resources (OPAC, databases, link resolver, federated search tool, community information) and using an improved search algorithm (RightResult) provides search results in a “faceted” manner allowing the user to more easily find pertinent information.

Necessary Ingredients

File(s) containing your full-text holdings by vendor and database.

This file will serve as your “coverage database” against which full-text cross vendor searches will be run.

The most time-consuming part of maintenance as it requires regular updates and is only as good as data provided by the aggregator.

Necessary Ingredients cont.

Access to the database vendor administration module(s).

This is where you configure the databases so they know where to look for other coverage information when a non-full text link is provided in a search result.

EBSCOadmin

Link resolver configuration in WebBridge

Conventional wisdom seems to advocate configuring Resources first and then Origins. This way, the Origins will begin working as soon as configuration is complete.

WebBridge configuration is done through a web browser

More definitions

A Category, such as Full Text, Indexes and Abstracts, or Search Engines, is a group of Target Resources (which you can specify) that will be available as WebBridge links.

A Data Test is a library-defined criterion that determines whether to display a Resource link. Data Tests instruct WebBridge whether to display a resource based on the content from the originating source record or search.

Filters can be used to block Resources from being offered based on the origin from which the user begins the search.

A look at configuration...

Consortium Considerations

Authentication – different levels of access between members?

Aggregation – different databases between members?

How can this work using a single coverage database?

Individual coverage databases – new III product, beta-testing this summer

Resources

WebBridge Listserv WebBridge Wiki CSDirect – Tutorials, FAQ

Questions?