Virtual XML: A Toolbox and Use Cases for the XML World View

Although the Extensible Markup Language (XML) has gained in popularity and has resulted in the creation of powerful software for authoring, transforming, and querying XML-based business data, much information remains in non-XML form. In this paper we introduce an approach to virtualize data resources and thus enable applications to access both XML and non-XML sources. We describe the architectural components that enable virtual XML — a toolbox that includes a cursor model, an XML-view mechanism such as the view created with the Data Format Description Language (DFDL), and XML processing languages. We illustrate the applicability of virtual XML through a number of use cases in various environments. We discuss the products that we expect from vendors and the open-source community and the way enterprises can plan to take advantage of virtual XML developments. Finally, we outline future research directions that include a vision of virtual XML that covers large-scale structures such as entire file systems, databases, or even the World Wide Web.