Fuzzy Analysis for Assessing Trust Space Within Wireless Sensor Networks

Wireless sensor nodes deployed outdoor often subject to environmental uncertainties, which challenges trusted data communications and error-free decision making. We developed a fuzzy logic framework to analyze the trust of an outdoor deployed data sensor (DS) within a wireless sensor network (WSN), where we selected three trust factors: weather index, battery residual and group deviation as input membership functions and generated trust values as an output membership function. A combination of trapezoidal and triangular membership functions with five linguistic variables were selected to define the input trust factors and a defined set of rules were applied to Sugeno Fuzzy inference systems (FIS) to assess the trust. The fuzzy framework verified the sensors trust at the gateway prior communicating the data to the central server, thus avoiding energy consumption on untrusted data communications. The simulation results revealed that Sugeno FIS demonstrated 36% energy savings against normal transmission by hopping untrusted data communications.