Active systems have been proposed as a paradigm to satisfy theneeds of many databases and other applications that require a timelyresponse to situations. Event-Condition-Action (or ECA) rules (S.Chakravarthy et al., 1989) are used to capture the active capability ina system. The utility and functionality of active capability (ECA roles)has been well established in the context of databases. In order for theactive capability to be useful for a large class of advancedapplications, it is necessary to go beyond what has beenproposed/developed in the context of databases. Specifically, extensionsbeyond the current state of the art in active capability are neededalong several dimensions: i) make the active capability available fornon-database applications, in addition to database applications; ii)make the active capability available in distributed environments; andiii) make the active capability available for heterogeneous sources ofevents (whether they are databases are not). The objective of the paperis to provide an architecture and framework to support ECA rules fordistributed and heterogeneous systems. We describe the design of our ECArule service, the alternatives considered at each step and the reasonsfor our choice of a particular alternative. Finally we draw conclusionsabout the architecture of our system and the utility of our system for awide range of applications
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