Ad-hoc network is a collection of dynamic nodes it means any node can join the network and leave the network any time.Wireless communication is less secure than wired communication and that’s why it is the vulnerability of mobile ad-hoc network and any threat can easily affect the communication. Many types of attacks are developed today which badly crash the network and make the communication performance degrade. So for avoid these vulnerabilities and make network secure we propose the technique on SECURITY of mobile ad-hoc network. To provide the security of mobile ad-hoc network we generate new techniques for detection of black hole attack. the performance impact of a black hole attack on a mobile ad hoc network and compare it with our modified AODV routing protocol. The simulation work is carried out by OPNET Modeler. To analyze performance of our proposed algorithm we use performance metrics ex. Network throughput, network load, packet send and received, packet dropped and end-to-end delay. we have surveyed and compare the existing solutions to black hole
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