Abstract: A Mobile Ad-hoc Network (MANET) is self-configured and dynamic network that formed by collecting number of mobile nodes. One cluster consists of group of nodes. It is necessary to have a good and efficient cluster formation and cluster head selection algorithm which will connect other neighbouring node. Their communication should do in very less time. In MANET security is another prime concern. The open medium and wide distribution of nodes make MANET vulnerable to malicious attackers. To prevent from such intrusions need a system which will detects as well as prevent. This system detects and prevents the intrusion in the network on the basis of parameter (such as packet loss ratio, energy consumption, packet delivery delay), once detected restricts that intrusion to enter in the network by blocking the system information of that intrusion and broadcast this information to other cluster head to save energy and protects against Intrusion.

Keywords: Wireless Sensor Network, Cluster, Cluster Head, Intrusion Detection and prevention, Mobile Ad-hoc network (MANET).