The design and implementation of a P2P-based composite event notification system

The development of large, open, and heterogeneous distributed systems is becoming increasingly dependent on event services to bind together the components of an application in such a way that they are able to react to changes in other components. One way to distribute event notifications around a distributed environment is to use content-based publish/ subscribe communication. Such a system mediates between publishers of information and subscribers who sign up to receive information by routing messages across the network from their source to the point of subscription using the message content and the client subscriptions. Although content-based publish/subscribe has been used successfully to develop simple event notification systems, in which events are routed through from external publisher to external client, more complex systems are possible that create new events, known as composites, based on the detection of patterns of events. Composite event notification, however, poses a number of challenges, including network management and network routing. In this paper, we discuss the design and implementation of a composite event notification system over a Chord-based peer-to-peer network using JXTA, and how we have addressed these challenges