Cooperation among nodes is important in ad hoc networks since in such networks nodes depend on each other for forwarding packets. However, cooperation in such operations consumes nodes energy and recourses. Therefore, it is necessary to design incentive mechanisms to enforce nodes to forward packets when the source and destination of the packet are other nodes in the network. Route falsification attacks are easy to launch by malicious nodes in ad hoc networks. These nodes falsify data and routes in the network. Previous routing protocols in ad hoc networks inspired by game theory just consider that network consists of selfish nodes. In this work, we consider that the network consists of malicious nodes too. The focus of this paper is on anomaly detection techniques in order to exploit their main advantage of being able to detect unknown attacks. First, we briefly describe intrusion detection systems and then we suggest a distributed schema applicable to mobile ad hoc networks. This anomaly detection mechanism is based on a neural network and is evaluated for packet dropping attacks using features selected from the MAC layer.

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Emergent Self Organizing maps Denial of Service Intrusion Detect ion Wireless Ad Hoc Networks Neural Networks