Evaluation of collaborative selfish node detection in MANETS and DTNs.

ABSTRACTMobile ad-hoc Networks (MANETs) and Delay Tolerant Networks (DTN) rely on network cooperation schemes to work properly. Nevertheless, if nodes have a selfish behaviour and are unwilling to cooperate, the overall network performance could be seriously affected. The use of watchdogs is a well-known mechanism to detect selfish nodes. Nevertheless, the detection process performed by watchdogs can fail, generating false positives and false negatives that can induce a wrong behaviour. In this paper we propose a collaborative watchdog approach based on the diffusion of selfish nodes awareness, that reduces the impact of false positives and false negatives. In order to evaluate the efficiency of our approach, we introduce an analytical model to evaluate the time of detection and the induced overhead of our collaborative watchdog. The results confirm the efficiency of our approach since the detection time of selfish nodes is reduced, the overall overhead is very low, and the impact of false positives and false negatives is minimised.