Exponential reliability factor based mitigation mechanism for selfish nodes in MANETs

Reliable dissemination of data in mobile ad hoc networks mainly depends on the cooperation among all the active mobile nodes present in the network. however,enforcing a node to cooperate with all the other mobile nodes is a difficult task. moreover,the mobile nodes in an ad hoc network have limited battery power and hence they refuse to forward their neighbor nodes' packets so as to conserve their energy. this intentional selfish behavior of mobile nodes reduces the degree of cooperation between active mobile nodes which in turn affects the network performance. hence,a need arises for formulating a reputation mechanism which helps in isolating selfish nodes in manets. in this paper,we propose an exponential reliability factor based mitigation mechanism (erfbm) for detecting and isolating selfish nodes. this erfbm efficiently isolates selfish nodes with the aid of exponential reliability factor (erf) computed based on the first and second hand information obtained from the mobile nodes. the effective performance of erfbm is extensively studied through ns-2 simulations and the results obtained clearly portray that the proposed erfbm isolates selfish nodes at a faster rate of 36% than the considered benchmark mitigation mechanisms such as record and trust-based detection (rtbd),reliability factor based mitigation mechanism (rfbmm) and packet monitoring conservation algorithm (pcma). the simulation study also depicts that erfbm on an average,improves the performance of the network by reducing the communication overhead by 21%,29% and 34% more than the three benchmark mitigation mechanisms considered for investigation.