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The Open GIS Consortium Inc. (OGC), Wayland, Mass., recently approved two new compliance tests and a series of tools to encourage software developers to validate software products that implement OpenGIS Specifications. A new website (www.opengis.org/resources/?page=testing) provides automated testing for Web Map Service 1.1.1 (WMS) and Web Feature Service 1.0 (WFS), a Geography Markup Language (GML) validation tool and links to reference implementations. Developers that successfully test for compliance with WMS and WFS specifications and want to claim or indicate compliance of their product in the marketplace must submit their results for validation, and pay a trademark licensing fee.
Compliance certification assures buyers that a vendor's product correctly implements OpenGIS specifications.
The tests and resources are the result of work on the Compliance & Interoperability Test & Evaluation Initiative (CITE). CITE was sponsored by the European Union Satellite Center (EUSC), which sees the benefit of using standards-based software, and needed a way to insure its purchases of commercial off the shelf products meet its interoperability requirements.
The Compliance Tests
OGC commissioned a planning study from The Open Group, an organization with a 20-year history of testing for the information technology community. The WMS and WFS test development teams were led by Northrop Grumman Information Technology and Galdos Systems respectively. The tests were ultimately implemented in collaboration with The Open Group, Galdos, and Northrop Grumman Information Technology.
CITE relied on OGC's consensus process to build and put the tests through their paces. Research indicates that automated compliance tests developed via consensus tend to be far more successful than those developed by a single organization and later accredited by an outside firm.
The number of OpenGIS Specifications has jumped in the past few years. The compliance tests are freely available to any developer who wants to test an implementation of WMS or WFS interface specifications. However, only those organizations that submit completed paperwork and appropriate fees can claim compliance in their sales and marketing literature.
The CITE Portal and Other Tools
The CITE portal (http//cite.occamlab.com) was developed by Sinclair Knight Merz and Social Change Online (SCO), both from Australia, using SCO's AIMS content management system. The portal includes access to the two compliance tests, along with other resources OpenGIS software developers will find useful.
The GML validator, developed by Galdos Systems, can be used to examine GML schema documents and insure that a given GML application schema follows the rules defined in the GML 3.0 specification. The WFS test relies on the GML validator. The portal also includes links to two websites that implement OGC reference implementations of WMS and WFS. A reference implementation is a live example that works exactly as one or more OpenGIS specification states. It is a community resource for testing and learning about the specification. The sites will be available in the coming weeks. The reference implementation team was lead by The Open Planning Project with team members from the University of Leeds (UK), lat/lon (Germany) and the National Center for Atmospheric Research (U.S.).
The software used on the reference implementations is open source and available for free download from the CITE portal. While some developers may wish to test clients against the hosted servers, other may want to "look under the covers" to learn more about the implementations.
Looking forward, there is still more work to do. Construction of tests for additional OpenGIS specifications is being planned. Per an Open Group study recommendation, OGC is considering holding "plug fest" events, where developers can test and demonstration interoperability between different compliant product offerings.
The CITE Initiative is part of OGC's Interoperability Program, a global, collaborative, hands-on engineering and testing program that rapidly delivers proven candidate specifications into OGC's Specification Program, where they are formalized for public release. In OGC's Interoperability Initiatives, international teams of technology providers work together to solve specific geoprocessing interoperability problems posed by the Initiative's Sponsors.
Source: OGC, Nov. 7, 2003