Complex Event Detection in Extremely Resource-Constrained Wireless Sensor Networks

Abstract

Complex Events are sequences of sensor measurements indicating interesting or unusual activity in the monitored process. Such events are ubiquitous in a wide range of Wireless Sensor Network (WSN) applications, yet there does not exist a common mechanism that addresses both the considerable constraints of WSNs and the specific properties of Complex Events. We argue that Complex Events cannot be described using standard threshold-based or composite logic approaches and attempting to represent them as such can lead to unpredictable execution cost while detection accuracy suffers from erroneous recording of observations which are common in WSNs. To address this, we develop a family of Complex Event Detection (CED) algorithms based on online symbolic conversion of sensor readings. With fixed execution cost and modest resource requirements, the CED algorithms cater for exact, approximate, non-parametric, multiple and probabilistic detection that is neither application nor data dependent. Overall, full implementation and simulations provide experimental evidence of the advantages of the proposed approach. We find that the proposed algorithms minimise configuration, promote

Study and Prediction of Wireless Link Quality for Adaptive Channel Hopping

“…Finally, we worked out the link quality symbol expression of consecutive N indicators before every error burst with length L max . Symbol Aggregation approximately (SAX) [19] is a kind of operationally simple method. Michael Zoumboulakis implemented SAX in wireless sensor network.…”

“…Michael Zoumboulakis implemented SAX in wireless sensor network. By pattern matching, he achieved high accuracy [19] to detected environment events, and, advantages like high speed, low resource consumption. The results show that this algorithm is applicable for wireless sensor network environment.…”

Piecewise aggregate representations and lower-bound distance functions for multivariate time series

“…There are many applications regarded to SAX. Zoumboulakis and Roussos [30] developed a family of Complex Event Detection (CED) algorithms based on online symbolic conversion of sensor readings. The symbolic conversion is indeed the algorithm of SAX.…”

Heuristic strategies for assessing wireless sensor network resiliency: an event-based formal approach

“…), we adopt an event-based formal language. In particular, among several eventbased formal languages, we choose event calculus (Shanahan, 1999), since its simplicity, its wide adoption in the sensor networks arena (Boonma and Suzuki, 2010;Zoumboulakis and Roussos, 2011;Bromuri and Stathis, 2009;Blum and Magill, 2011) and the possibility to formally analyze the behavior of a system as event flows, offering simple ways to evaluate the reliability metrics of our interest.…”

“…Formal methods are widely adopted in the literature to verify the correctness of a WSN specification at design time (Boonma and Suzuki, 2010;Zoumboulakis and Roussos, 2011;Bromuri and Stathis, 2009;Blum and Magill, 2011). They appear to be particularly suitable for applying heuristic strategies adopted in the WSN field.…”