Mobile Ad hoc Network (MANET) is a self configuring network of mobile nodes connected by wireless links and considered as network without infrastructure. Securing MANETs is an important part of deploying and utilizing them, since they are often used in critical applications where data and communications integrity is important. Existing solutions for wireless networks can be used to obtain a certain level of such security. These solutions may not always be sufficient, as ad-hoc networks have their own vulnerabilities that cannot be addressed by these solutions. In the network, some malicious nodes pretend to be intermediate nodes of a route to some given destinations, drop any packet that subsequently goes through it, is one of the major types of attack. We propose a cooperative method to detect malicious nodes in MANETs. The mechanism is cooperative because nodes in the protocol work cooperatively together so that they can analyze, detect malicious nodes in a reliable manner. We verify our method by running simulations with mobile nodes using Ad-hoc on-demand Distance Vector (AODV) routing. It is observed that the malicious node detection rate is very good; the overhead detection rate is low, packet delivery ratio is little bit high and also the response time is observed when there is a change of mobility speed.

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MANET Malicious Overhead Packet delivery ratio Black hole AODV