Blending Complex Event Processing with the RETE Algorithm

Modern event-driven applications implement sophisticated and highly specialized algorithms for detecting and correlating events from event streams or clouds. The correlation logic and resulting actions are declaratively defined as EA (event action) rules. An EA language allows the definition of complex correlation rules with the help of logical, temporal, content-based and other operators. On the other hand, production rule systems provide a declarative means to express and compute CA (condition action) rules. CA rules define constraints. The most prominent scientific and commercial production rule systems rely on the RETE algorithm in order to efficiently compute CA rules. As the industry is on the way towards a loosely coupled service-oriented and eventdriven architecture, there is a high demand for an integrated solution of computing ECA (event condition action) rules. In this paper we give a survey of already finished as well as ongoing research in the field of combining event processing algorithms with the RETE algorithm. We compare the different approaches and present our approach of combining SnoopIB, a specialized event detection algorithm, with the RETE algorithm.