International Journal of Science and Modern Engineering (IJISME)
Mobile ad-hoc network is huge area for research with practical applications. It is a infrastructureless and self-organized network, vulnerable because of its characteristics such as open medium, distributed cooperation and it is difficult to predict the topology. In general, Routing security in MANETs appears to be a challenging task. In this paper, the authors study the routing security issues of MANETs, and analyze in detail - the \"Blackhole\" attack. They come with distributed reputation mechanism that improves security in MANETS. Some optimization to the current reputation scheme used in MANETs are one is Selective Deviation tests and second is Adaptive expiration timer that aims to deal with congestion and quick reputation convergence.