On the Need for Distributed Complex Event Processing with Multiple Sinks
Samira Akili · 2019
Distributed complex event processing evaluates CEP-queries over data produced by geographically distributed sources. To cope with bandwith restrictions, it is common to employ in-network processing where the operators of a query are placed at network nodes, especially those that act as data sources. While existing operator placement algorithms handle distributed sources, query results are gathered at one designated node -- the sink. We argue that such single-sink solutions are not applicable for non-hierarchical systems, in which multiple nodes need to be informed about query results. Also, in compositional applications, where the result of one query is the input to another query, having a single sink enforces centralisation. Using a real-world application scenario, we illustrate the need for a novel DCEP approach with a multi-sink operator placement. Furthermore, we elaborate on the requirements to be incorporated by a DCEP approach targeting highly decentralized systems.