Employing fuzzy trust levels to improve wireless network reliability

Wireless Ad-hoc networks consist of wireless devices that communicate with each other without the need for a management infrastructure. As such, the very basic operation of Ad-hoc networks is dependent on the cooperation of their nodes to provide connectivity and communication routes. In practice though, such cooperation may not always be achieved. Cases where some nodes behave in a selfish manner or maliciously are of particular interest and consequence. Such cases normally result in degradation of the performance of the network or even disruption of its operation altogether. To mitigate the effect of such nodes and to achieve higher levels of reliability, the communications paths should try to avoid using them. In other words, the rout should be based on reliable and trustworthy nodes. In turn, that does necessitate evaluation of trust and trustworthiness of the nodes. This paper proposes an approach that is based on soft computing to establish quantifiable trust levels between the nodes of an Adhoc network. The trust levels are then used in the routing decision making process. Extensive simulator studies that utilize the proposed approach are carried out, analyzed, and reported in this paper. The resulting relatively significant improvements in the performance of typical Ad-hoc networks are also reported here