Wireless Ad-hoc networks: Using fuzzy trust approach to improve security between nodes

A wireless ad-hoc network is a collection of mobile nodes that can be deployed without the need for any centralized management infrastructure. The operation of ad-hoc networks depends on the cooperation among nodes to provide connectivity and communication routes. However, such an ideal situation may not always be achievable in practice. Some nodes may behave maliciously, resulting 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 security and reliability, this paper expands on relevant fuzzy logic concepts to propose an algorithm to establish quantifiable trust levels between the nodes of ad-hoc networks. These trust levels are then used in the routing decision making process. Using OPNET simulator, the proposed algorithm is validated and further studied. The findings show that when the proposed algorithm is utilised, the overall performance of the ad-hoc network is significantly improved.