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CHAPTER 9
<schemaInfo>
<schema identifier=“info:srw/schema/1/marcxml-v1.1” sort=“false”
name=“marcxml”>
<title>MARCXML</title>
</schema>
<schema identifier=“info:srw/schema/1/dc-v1.1” sort=“false” name=“dc”>
<title>Dublin Core</title>
</schema>
<schema identifier=“info:srw/schema/1/mods-v3.5” sort=“false”
name=“mods”>
<title>MODS v3.5</title>
</schema>
</schemaInfo>
Given all the benefits associated with SRU/W, it has been puzzling why so
few applications, tool sets, or organizations currently support the protocol.
By contrast, after nearly fifteen years, the Z39.50 protocol, despite its cryp-
tic communications format and spotty character-encoding support, still
remains the predominant method for searching and retrieving bibliographic
data in the library environment. This isn’t to say that a handful of large
SRU/W implementations doesn’t exist. The Library of Congress provides a
robust SRU/W API for its library catalog, as do projects like the European
Digital Library (www.theeuropeanlibrary.org). Additionally, vendors like Ex
Libris encourage users to utilize their built-in SRU service over the tradi-
tional Z39.50 connection (though both exist). However, after being available
and in production for nearly fifteen years, the tools or software to support
the SRU/W standard remain few and far between. What’s more, given the
inconsistent implementation of SRU services and the trend among digital
library developers to create more RESTful-based services, it appears that
the desire to provide long-term support and maintenance for existing tools
capable of working with the SRU/W standard is very much on the wane.
OpenSearch
OpenSearch is an intriguing protocol when one considers how quickly it has
been adopted by developers outside the library community. OpenSearch was
developed in early 2004 by Amazon.com to allow resources to be integrated
into its A9 search engine. However, the simplicity of the protocol’s search
and response syntax has led to a very quick adoption within the corporate
community. So ubiquitous has OpenSearch become that all major web
browsers use it to configure new search endpoints in the browser.
As a protocol, OpenSearch functions very much like SRU/W in that it
works over an HTTP GET connection utilizing a very simple URL query
structure. What makes OpenSearch different is the response format. Open-
Search utilizes RSS (Really Simple Syndication) and the Atom Syndication
format as the response format. By utilizing these two formats, OpenSearch
has been able to successfully leverage tools that have traditionally been used
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