Exponential reliability factor based mitigation mechanism for selfish nodes in MANETs

Abstract

Reliable dissemination of data in mobile ad hoc networks mainly depends on thecooperation 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 hencethey refuse to forward their neighbor nodes’ packets so as to conserve their energy.This intentional selfish behavior of mobile nodes reduces the degree of cooperationbetween active mobile nodes which in turn affects the network performance. Hence,a need arises for formulating a reputation mechanism which helps in isolating selfishnodes in MANETs. In this paper, we propose an Exponential Reliability FactorBased Mitigation Mechanism (ERFBM) for detecting and isolating selfish nodes.This ERFBM efficiently isolates selfish nodes with the aid of Exponential ReliabilityFactor (ERF) computed based on the first and second hand information obtainedfrom the mobile nodes. The effective performance of ERFBM is extensively studiedthrough ns-2 simulations and the results obtained clearly portray that the proposedERFBM isolates selfish nodes at a faster rate of 36% than the considered benchmarkmitigation mechanisms such as Record and Trust-Based Detection (RTBD), ReliabilityFactor Based Mitigation Mechanism (RFBMM) and Packet Monitoring ConservationAlgorithm (PCMA). The simulation study also depicts that ERFBM on an average,improves the performance of the network by reducing the communication overhead by21%, 29% and 34% more than the three benchmark mitigation mechanisms consideredfor investigation.