Team presentation

Data handled by information systems is increasingly complex, distributed, heterogeneous, replicated, changing, and multi-formatted. The goal of the Verso project is to study fundamental problems and develop novel techniques for the management of such data. The goal is to build richer systems that are more open to the network and other software components.

The integration of data from a very large number of data sources is becoming increasingly important in the context of the Web. Such integration often requires combining techniques from artificial intelligence and databases. To facilitate this research, Verso has formed in 2001 a joint project together with the knowledge representation team (IASI) of the Laboratoire de Recherche en Informatique at Orsay (led by M.-C. Rousset).

Research themes

As a general trend, Verso is moving away from the centralized server approach used in Active Views and Xyleme towards peer-to-peer solutions as exemplified by the Active XML approach. Specific research topics include the following:

• Warehousing XML data from the Web: pursuing work initiated in the framework of Xyleme, we study algorithms to detect changes in XML documents (XMLdiff), query optimization and the computation of page importance on the Web. We also started a new reserach direction on the creation and mining of thematic data collections.
• Active XML: we study the integration of data and Web services. Our approach is centered around XML documents that include declarative calls to Web services. The goal is to facilitate the development of applications open to the network, and the cooperative work of distributed clients.
• Querying heterogeneous data and optimization: we continue the work on XML indexing and heterogeneous data integration. New work deals with filtering of XML data using finite-state automata.
• Theory of data modeling : we study fundamental problems motivated by a data centric vision of computer science. We use tools from logic and complexity theory to understand the specific properties of computation on collections (relations) or irregular graphs (such as the Web).

International and industrial relations

• Initiated the DbGlobe European project on query processing over the Web.
• Initiated a French-Canadian project with U. Toronto on new services for the web.
• Within France, collaborations with the Vertigo Group, CNAM, Paris
• Industrial collaborations with the MatchVision start-up (that disappeared in 2001, GAEL RNRT Project) and Xyleme, a start-up originating in Verso.