Trust management for collusion prevention in mobile ad hoc networks

Reciprocity-based cooperation on packet relaying in mobile ad hoc networks discourages nodes from behaving selfishly. Before passing on a packet to the next hop a node verifies whether the sender of the packet is trustworthy (cooperative) or not. The quality of the evaluation of the trustworthiness relies on types of data used for description of the behaviour of the sender. In the literature a distinction was made between first-hand observations and observations obtained from third parties. This paper demonstrates that further distinction of such data into personal and general can help to create better protection against clique building among nodes. The former takes into account the status of packets originated by a node itself, while in the latter the status of packets originated by other nodes is considered. Computational experiments demonstrate that in the presence of a large number of selfish and colluding nodes prioritising the personal data improves the performance of cooperative nodes and creates a better defence against colluding free-riders.