Making Interoperation Tractable

A variety of solutions have been suggested for managing heterogeneity among data sources. We are developing a runtime environment and tools that support integration of online information processing services in digital libraries. We introduce canonical wrappers that provide logical abstractions for the native interfaces of components. They enable mediators to reason about interfaces of heterogeneous components in a uniform way. Mediator functionality is partitioned into a static and a dynamic part. The static part addresses data type conversion whereas the dynamic part deals with the behavior of components. Machine-readable declarative speci cations of mediators and component interfaces are stored on the Web using the Resource Description Framework (RDF).