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OpenURL is a type of Uniform Resource Locator (URL) intended to enable Internet users to more easily find a copy of a resource that they would be allowed to access. Though OpenURL can be used with any kind of resource on the Internet, it is most heavily used by libraries to help patrons find accessible scholarly articles.

The OpenURL standard is designed to support mediated linking from information resources, such as abstracting and indexing databases (sources), to library services (targets), such as academic journals, whether online or in printed or other formats. A "link resolver", or "link-server", parses the elements of an OpenURL and provides links to appropriate targets available through 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 of targets include full-text repositories, online journals, online library catalogs and other Web resources and services. A source is typically a database that indexes various types of information resources often found in libraries, such as articles, books, patents, etc. Some examples of such databases include Web of Science, Scifinder, Modern Languages Association Bibliography and Google Scholar.

The National Information Standards Organization (NISO) has developed OpenURL and its data container (the ContextObject) as American National Standards Institute (ANSI) standard Z39.88. On 22 June 2006, OCLC was named the maintenance agency for the standard.^[1]

Contents 1 Structure 2 Application 3 History 4 Current applications and tools 5 References 6 External links

[edit] Structure

An OpenURL consists of a base URL, which addresses the user's institutional link-server, and a query string, which contains contextual data, typically in the form of key-value pairs. The contextual data is most often bibliographic data, but as of version 1.0 OpenURL can also include information about the requester, the resource containing the hyperlink, the type of service required, and so forth. For example:

http://resolver.example.edu/cgi?genre=book&isbn=0836218310&title=The+Far+Side+Gallery+3

is a version 0.1 OpenURL describing a book. http://resolver.example.edu/cgi is the base URL of an example link-server. In version 1.0, this same link becomes somewhat longer:

http://resolver.example.edu/cgi?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:book&rft.isbn=0836218310&rft.btitle=The+Far+Side+Gallery+3

A breakdown of the query string above shows that the following values are set:

1. The URL Version url_ver = Z39.88-2004
2. Custom metadata rft_val_fmt = info:ofi/fmt:kev:mtx:book
3. And an object named "rft" is set which could be represented as rtf = { isbn:"0836218310", btitle:"The Far Side Gallery 3" }

[edit] Application

The most common application of OpenURL is to provide appropriate copy resolution: an OpenURL link points to the copy of the resource most appropriate to the context of the request. If a different context is expressed in the query, a different copy ends up resolved to; but the change in context is predictable, and does not require the creator of the hyperlink to handcraft different URLs for different contexts. For instance, changing either the base URL or a requester parameter in the query string can mean that the OpenURL resolves to a copy of a resource in a different library. So the same OpenURL, contained for instance in an electronic journal, can be adjusted by either library to provide access to their own copy of the resource, without completely overwriting the journal's hyperlink. The journal provider in turn is no longer required to provide a different version of the journal, with different hyperlinks, for each subscribing library. See also COinS.

[edit] History

OpenURL was created by Herbert Van de Sompel, a librarian at the University of Ghent, in the late 1990s. His link-server software, SFX, was purchased by the library automation company Ex Libris Ltd. which popularized OpenURL in the information industry.

[edit] Current applications and tools

Many companies now market link server systems, including Openly Informatics (1Cate — acquired by OCLC in 2006; rebranded as WorldCat Link Manager in 2007), Swets (SwetsWise Linker), Serials Solutions 360 Link (formerly known as Article Linker), Innovative Interfaces, Inc. (WebBridge), EBSCO (LinkSource), Ovid (LinkSolver), SirsiDynix (Resolver), Fretwell-Downing (OL2), TDNet (TOUR), WT Cox (Journal Finder), R.R. Bowker (Ulrichs Resource Linker) and Infor (Vlink).

There are also many open-source tools for manipulating OpenURLs and the Code4Lib community maintains a list of these. Open-source link resolvers include CUFTS, Umlaut and perhaps OLinks.

OpenURL is usually implemented by information providers by dynamically inserting an appropriate base URL into web pages sent to an authenticated user. OpenURL COinS is a new specification that allows free services like Wikipedia to provide OpenURLs by cooperating with client side software agents. Federated search software presents OpenURL links in record fields by employing the library's subscriber links to link servers facilitating access to full-text resources from bibliographic record hyperlinks.

[edit] References

[edit] External links

• The Lure of Linking - 4/1/2004 - Library Journal
• ANSI/NISO Z39.88-2004 The OpenURL Framework for Context-Sensitive Services at NISO
• OpenURL standardization committee - archives of OPENURL@OCLC.ORG mailing list
• openurl.code4lib.org
• OpenURLs COinS
• Apps, Ann; MacIntyre, Ross (May 2006). "Why OpenURL?". D-Lib Magazine 12 (5). doi:10.1045/may2006-apps. http://www.dlib.org/dlib/may06/apps/05apps.html. 
• Van de Sompel, Herbert; Beit-Arie, Oren (March 2001). "Open Linking in the Scholarly Information Environment Using the OpenURL Framework". D-Lib Magazine 7 (3): 34826. doi:10.1074/jbc.M004545200. PMID 10942764. http://www.dlib.org/dlib/march01/vandesompel/03vandesompel.html.