IBM® WebSphere® DataPower® SOA Appliances are initially configured using an interactive Web GUI-based console. Operational interfaces like IBM Tivoli® Composite Application Manager System Edition push XML-encoded rules into one or more appliances in a cluster. Automated scriptable interfaces and Web services endpoints also enable rich management. This article presents an alternative approach in which simple rules are stored outside the appliances and interpreted by them on demand. Using some common Web and Web services patterns, this approach similarly enables management when several appliances are in use. By directing message routing rules to an external, shared storage location, this technique can simplify the task of appliance management by minimizing changes made to each device, by centralizing more frequently changed metadata, and by assisting integration with third party tools. This technique can be generalized beyond routing rules to other uses as well.
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