Abstract

Wireless sensor networks (WSNs) are composed of a large number of sensor nodes that are self-
organized. The open nature of WSNs makes them easily exposed to a variety of attacks and brings
many security challenges. Furthermore, because of the potentially dynamic behavior of WSNs, there
is hardly any infrastructure or centralized control. To enhance the security in WSNs, it is necessary
to evaluate the trustworthiness of nodes since some of them may refuse to forward packets for sav-
ing their limited resources. In this paper, we propose a fuzzy-based trust management in WSNs.
All neighbors of one nodes are ranked by their trust value. Only those with higher trust values can
be chosen to forward packets. Our trust model exploits multiple metrics, rather than a single met-
ric, and converts them into a single numerical ranking. We perform an thorough evaluation of our
proposed approach. The results indicate that our trust model can not only identify abnormal nodes’
behaviors, but can also reduce query traffic while improving the reliability of the exchange messages.