Complex Event Processing over distributed probabilistic event streams

With the rapid development of Internet of Things (IoT), enormous events are produced everyday. Complex Event Processing (CEP) is the key part of the IoT middleware. Since current hardware and wireless communication techniques cannot support 100% confident data, CEP engine which can report confidence for processed complex events over uncertain data is needed. Most of the current study of complex event processing has not considered much about how to process complex event over distributed probabilistic event streams and large sliding window. In this paper, a high performance complex event processing method over distributed probabilistic event streams is proposed. This method uses probabilistic Nondeterministic Finite Automaton and Active Instance Stacks to process complex event in single probabilistic event stream. Multiple processes can run parallel to improve the performance. A query plan based method using tree data structure is used to process hierarchical complex event from distributed event streams. Query plan optimization is proposed based on query optimization technology of probabilistic databases. The experimental study shows that this method is efficient to process complex events over distributed probabilistic event streams.