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GILS in the NSDI and NBII
- GILS, NSDI Clearinghouse, and NBII Clearinghouse
GILS, NSDI Clearinghouse, and NBII Clearinghouse implementations build upon the ISO 23950
international standard for information search. ISO 23950 itself provides a mechanism for
search sessions over a network but does not require that specific services are supported.
The specification of the services needed to implement a search mechanism are given by
various content standards and ISO 23950 Profiles.
- ISO 23950
ISO 23950 is the international standard for information search, equivalent to the U.S.
standard designated ANSI/NISO Z39.50. ISO 23950 was developed primarily in the library and
information services communities, though now it is very broadly applied worldwide on
Internet and other networks. It supports full-text search but also supports large, complex
information collections. While it leverages common practice, ISO 23950 does not enforce
any particular format. It does not specify how network servers manage records or how
clients use records, only how to express a search and return results.
- National Spatial Data Infrastructure (NSDI)
The National Spatial Data Infrastructure (NSDI) is a community of interest within the U.S.
National Information Infrastructure. U.S. public law and various policies specify GILS for
finding and retrieving information throughout the National Information Infrastructure. The
Federal Geographic Data Committee (FGDC) focuses U.S. Federal activities in the NSDI. The
FGDC approved the Content Standard for Spatial Metadata to guide creation of facilities
for finding and retrieving information throughout the NSDI. The Content Standard for
Spatial Metadata inherits the metadata content given in the GILS Profile and provides
further elaboration peculiar to spatial data.
- NSDI Spatial Data Clearinghouse
A user with client software for finding NSDI locator records will have no trouble finding
everything being made accessible according to the GILS Profile. A user with client
software that is GILS compliant but not compliant to the Content Standard for Spatial
Metadata will be able to find NSDI locator records generically, but won't be able to
refine the search according to detailed spatial criteria.
- National Biological Information Infrastructure (NBII)
The NBII is an electronic gateway to biological data and information maintained by
federal, state, and local government agencies; private sector organizations; and other
partners around the nation and the world.
- NBII Clearinghouse
The NBII Clearinghouse is an initiative to help users locate, evaluate, and access
biological data and information from a distributed network of cooperating data and
information sources. The Clearinghouse also provides access to software tools to use in
analyzing, integrating, and applying biological data.
The NBII Metadata Clearinghouse contains standardized metadata-based descriptions of
biological data sets and information products. Metadata descriptions follow the NBII's
Biological Profile of the Federal Geographic Data Committee's (FGDC's) Content Standards
for Digital Geospatial Metadata. The NBII Clearinghouse is also a participating node on
the FGDC's National Spatial Data Clearinghouse.
- Content Standards and ISO 23950 Profiles
Content standards for the bibliographic community have been in development for more than
150 years. Current examples include Machine Readable Cataloging, Anglo-American Cataloging
Rules, and Electronic Archival Descriptions. Such standards have been further elaborated
to address non-bibliographic information resources. Similar to cataloging records, such
"locator records" use content standards such as the Content Standard for Spatial
Metadata and various derivatives.
Four ISO 23950 Profiles comprise a family of standard search mechanisms used in GILS, NSDI
Clearinghouse, and NBII Clearinghouse implementations. These four profiles are nested from
simple to more precise in the following order: WAIS, GILS, GEO, and Biological. (The ISO
23950 Catalog Interoperability Profile, not addressed in NSDI or NBII, is more precise
than GEO but does not encompass Biological.)
These four profiles are constructed so that a server compliant with a more precise profile
is automatically compliant with all simpler profiles. For example, a server compliant with
the GEO Profile is also compliant with the GILS Profile and the WAIS Profile. The
selection of an appropriate server profile depends on both the desired precision of
searching and the availability of necessary metadata elements in the available records.
Because ISO 23950 was developed first in the library community, there is a widespread
support of bibliographic searching using the standard Bib-1 Attribute Set. Although Bib-1
is an Attribute Set rather than an ISO 23950 profile, Bib-1 does provide a registered set
of common search attributes used in ISO 23950 profiles.
The following table summarizes the nested relationship of the four profiles and the Bib-1
|Record elements available
||ISO 23950 Specification
||Broad searching, not precise
|Bibliographic (e.g., title, author, subject, date) plus text
||Bibliographic searching (but no interoperability profile)
||Bib-1 attribute set
(not a profile!)
|Metadata plus bibliographic and text
||Federal GILS, State GILS, GELOS, CIESIN, etc.
||Focused searching, good precision, wide interoperability
||GILS Profile (superset of WAIS, includes Bib-1)
|Geospatial metadata plus bibliographic and full-text
||Precise searching, includes lat/long
(superset of GILS)
|Biological metadata plus geospatial, bibliographic and full-text
||Precise searching, includes lat/long and taxonomy terms
(Superset of GEO)
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