VII · 45

Origins

OpenURL grew out of late-1990s frustration at libraries: a single hardcoded link in a database could not deliver every reader to the copy their institution actually licensed.

The appropriate-copy problem

By the late 1990s libraries subscribed to many overlapping electronic resources: bibliographic databases, full-text aggregators and publisher platforms, each emitting its own links. A link from a database usually went to one publisher's site or one aggregator, whether or not the reader's institution had access there. The standard's foreword describes the issue identified at NISO's reference-linking workshops (from 1999) as the appropriate-copy problem: "multiple copies of a resource exist, and each copy is governed by a different access policy", and the user should reach a copy whose policy matches their privileges.

SFX at Ghent

Herbert Van de Sompel and Patrick Hochstenbach at Ghent University described their SFX linking server in a series of D-Lib Magazine articles in 1999 ("Reference Linking in a Hybrid Library Environment", parts 1–3), including an experiment run jointly with Los Alamos National Laboratory. The idea was to separate the citation from its destination: sources emit a description of the item, sent to a per-institution server that knows what the institution licenses. That server, later called a link resolver, chooses the destination. Ex Libris acquired SFX and turned it into one of the first commercial link resolvers.

Van de Sompel, Hochstenbach and Oren Beit-Arie of Ex Libris published the OpenURL syntax description, dated 16 May 2000. The standard later named it "OpenURL 0.1". Publishers, abstracting-and-indexing services, preprint servers and Crossref adopted it quickly, making it a de facto standard.

The path to NISO

NISO formed Standards Committee AX in 2001 to develop a formal standard. Its starting point was the "Bison-Futé model" (Van de Sompel and Beit-Arie, D-Lib Magazine, July/August 2001), which generalised the information in an OpenURL 0.1 request into a ContextObject with six Entities. The committee built a general framework around it, with KEV and XML formats, a Registry of named components, three transports and Community Profiles, and kept an upgrade path from 0.1 through the Inline transport.

The result, ANSI/NISO Z39.88-2004, The OpenURL Framework for Context-Sensitive Services, was approved by ANSI on 15 April 2005. In 2006 NISO designated OCLC as maintenance and registration agency; OCLC Research ran the OpenURL Registry at openurl.info.

Reaffirmation

NISO reaffirmed the standard on 13 May 2010, confirming that it stays in force without substantive change. Z39.88-2004 (R2010) is the current version. The Registry was frozen in 2022; see Registry Deprecation.

Sources