Mitigation of the effects of selfish and malicious nodes in ad-hoc networks

A wireless Ad-hoc network is a group of wireless devices that communicate with each other without utilising any central 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 approach 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 and MATLAB simulators, the proposed approach is validated and further studied. The findings show that when the proposed approach is utilised, the overall performance of the Ad-hoc network is significantly improved.