From beginning of 1994 to the end of 1996, the IRO-DB ESPRIT project has developed tools for accessing relational and object-oriented databases in an integrated way. The system is based on the ODMG standard as pivot model and language. It consists of three layers. The local layer provides for an ODMG interface to heterogeneous DBMSs, the communication layer implements object-oriented remote data access, and the interoperable layer supports design and querying of integrated views. This paper describes the architecture and main design choices of IRO-DB, and reviews them against the experiences gained with implementation and application. It concludes with analyzing the revisions and extensions needed for applying the developed technology to inter- and intranet federations, which are tackled in the follow-up ESPRIT project MIRO-Web.
Peter Fankhauser, Georges Gardarin, M. Lopez, J. M