Intelligent Routing based on Active Patterns as the basis for the integration of distributed information systems

Nikolaos Skarmeas and Keith L. Clark


Modern Information Systems (IS), in networking environments, in addition to communicating with clients, communicate with each other in order to provide a wider variety of services and successfully accomplish tasks they are requested to do. A mechanism for facilitating the client-IS and IS-IS communication is presented. The approach is based on an {\em active message board} which provides a means for content based intelligent routing. It is a shared medium that ISs can be attached to and register active patterns. When a message arrives at the board, it is tested using the the stored active patterns and the message is forwarded to all (or some) of the ISs that registered a successfully matching pattern, the potential destinations for the message. How many of these potential destinations are sent the message is determined by the qualifications attached to te message by the sender.

The patterns are active in the sense that they are function closures which can contain semantic tests on the content of the message, known only to and defined by the IS that registered the pattern. They can also include message sends and receives, and hence communicate components of the message, even the identity of the sender, in a query to the IS to see if it wants to be treated as a potential destination of the message at this time. Multiple message boards can be defined and structured hierarchically, in order to avoid bottleneck problems and provide an enhanced routing service.

As the implementation platform, a distributed process oriented programming language called April has been used. Its advanced features allow the easy implementation of the presented framework.

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