Cooperative Black Hole Node Detection by Modifying AODV

The black hole attack is a well known severely occurring security threat in wireless mobile ad hoc networks. A black hole is a malicious node that spuriously replies for any route request without having any active route to the specified destination. It then absorbs all the data packets and drops them fully or sometimes partially so that the destination node will not be able to get the data packets results in affecting the PDR (packet delivering ratio) to a great extent. Sometimes the Black Hole Nodes cooperate with each other with the same aim of dropping packets these are known as cooperating Black Hole nodes and the attack is known as Cooperative Black Hole attack. In this paper our goal will be on proposing an algorithm for detecting these cooperative black hole nodes in the network and propagating this information throughout the network. Our focus specifically, is on ensuring the security against the Black hole attacks.