A novel flexible trust management system for heterogeneous wireless sensor networks

Security has been recognised as a key issue for the expansion of wireless sensor network applications. To defend against the wide set of security attacks, legacy security solutions are not applicable due to the very limited memory and processing resources of the sensor nodes as well as due to the reason that sensor networks are required to operate in an autonomous infrastructureless manner. Trust management schemes consist a powerful tool for the detection of unexpected node behaviours (either faulty or malicious). Once misbehaving nodes are detected, their neighbours can use these information to avoid cooperating with them either for data forwarding, data aggregation or any other cooperative function. We propose a novel trust management system based on both direct and indirect trust information, which allows for fast detection of a wide set of attacks, including those addressing the reputation exchange scheme, while energy awareness is also incorporated in our approach.