A dynamic query scheduling framework for distributed and evolving information systems

The rapid growth of the wide area network technology has led to an increasing number of information sources available online. To ensure the query services to scale up with such dynamic open environments, an advanced distributed information system must provide adequate support for dynamic interconnection between information consumers and information producers, instead of just functioning as a static data delivery system. We develop a distributed query scheduling framework to demonstrate the feasibility and the benefit for supporting interoperability and dynamic information gathering across heterogeneous information sources, without relying on an integrated view predefined over the participating information sources. We outline the mechanisms developed for the main components of our distributed query scheduling framework, such as query routing and query execution planning services. We also provide a concrete example to illustrate the issues on how the information consumers' query requests are dynamically processed and linked to the heterogeneous information sources and how the query scheduling framework scales up as the number of information sources increases.