Ensuring Security Through Trust in Mobile Ad-Hoc Networks Using Soft Computing Methods

In mobile ad-hoc networks (MANETs), a node has to interact with unknown nodes in establishing the network. The applications are run successfully, if all the nodes are cooperative. In MANET, usually a node switches to selfish mode when it is short of resources, and it may not cooperate in running neighbor applications. This chapter discusses trust definitions, properties, prediction, aggregation, propagation, and computation methods in the MANET context. It also discusses different trust attacks in MANETs and their countermeasures. The chapter further discusses soft computing methods in trust estimation discussed like fuzzy logic, fuzzy petrinets, Bayesian conditional probability, Dempsters Shafer Theory, and trust matrix operations. The computed trust values have to be shared among the nodes in the network, so that the trust recomputation works can be avoided for the same node.