Electronic Resources in the Virtual Learning

Cross searching: Z39.50 to MetaLib
One of the first areas where interoperability and standards were required
was in the field of information retrieval and specifically library
catalogues or OPACs. The Information Retrieval (Z39.50) Application
Service Definition and Protocol Specification was an important
development and is discussed by Lynch (1997) who provides an
overview of developments since the 1970s. He defines Z39.50 as:
… a protocol which specifies data structures and interchange rules
that allow a client machine (called an ‘origin’ in the standard) to
search databases on a server machine (called a ‘target’ in the
standard) and retrieve records that are identified as a result of such a
search.
Z39.50 facilitates cross searching of resources and the construction of
union catalogues, which was an important feature of many of the eLib
Projects. Z39.50 refers its NISO standard number, and it has also
become an international standard with ISO number 23950.
The vast majority of modern library management systems comply with
the Z39.50 standard. The standard is one of the core technologies at the
heart of portal developments that is leading to an increasing overlap
between e-learning solutions and digital libraries. Cross searching of a
variety of electronic resources in addition to the library catalogue is now
possible with library portal technology. Various commercial library
management systems offer portal products, including MetaLib
14
from
ExLibris, ENCompass
15
from Endeavor and ZPortal
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from Fretwell-
Downing to name but a few. There are also a number of open source
solutions, such as MyLibrary, that were discussed earlier in this chapter.
A review of library portals was undertaken by Cox and Yeates (2002)
who state:
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Z39.50 and Dublin Core are the core underlying
standards/technologies in use … we see this increasingly being
superseded by XML (XPath, XML Query, XQuery, XSLT) and the
notion of web services. (Cox and Yeates, 2002, p. 4)
Boss (2002) maintains that most portals have the following features:
intuitive and customisable web interface, personalised content
presentation, security and communication and collaboration tools.
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Cox (2003) argues that the core function of portals is the cross searching
of resources and providing the appropriate copy of resources using
OpenURL (this is discussed later in this chapter). JISC recently funded a
project to examine the implementation of one library portal at
Loughborough University (Hamblin and Stubbings, 2003). The project
found that the portal led to a dramatic increase in the use of electronic
databases. In any case, there are obvious overlaps between library
portals and virtual learning environments and the importance of a
library portal interacting with the VLE is paramount:
This could mean somehow offering management services to resources
embedded in course materials. For example, such systems might be
used to manage readings lists or collections of relevant resources that
would be viewed through the VLE. (Cox and Yeates, 2002, p. 9)
Electronic journals and standards
There is in general a lack of specifically targeted standards for e-journals,
although a number of technical standards are having an impact on their
publication and on access to them. Standards in areas such as metadata,
identifiers and traditional cataloguing are becoming important, with
three emerging standards: OpenURL and DOI (Digital Object Identifier)
to facilitate reference linking, and ONIX for Serials, a metadata
standard, to support business applications in the serials publication
sector. Perhaps one of the greatest challenges presented by electronic
journals is also maintaining up-to-date title and subject lists of resources
and locating appropriate copies of an item. Many new e-journal
solutions have therefore come onto the market, including products such
as SFX, Xrefer and Serials Solution.
Journal articles are identified as discrete ‘digital objects’ and there is a
number of relevant recent standards for identifying digital and other
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Standards, specifications and access management
objects. These include SICI (Serial Item and Contribution Identifier) code
and DOI. Schemes for persistent names for Internet addresses have also
been developed, most notably OCLC’s PURL (Persistent URL) system,
CNRI’s Handles and the OpenURL.