Multiple Black Hole Node Attack Detection Scheme in MANET by Modifying AODV Protocol

Mobile Ad hoc Networks (MANET) is a self-configuring, infrastructure less network consists of independent mobile nodes that can communicate via wireless medium. Each mobile node can move freely in any direction, and changes their links to other devices frequently. Security is an essential part of ad hoc networks. Due to its dynamic topology, resource constraints, no centralized infrastructure and limited security, it is vulnerable to various attacks and black hole attack is one of them. In this attack, the malicious node advertises itself as having the shortest path to the destination and falsely replies to the route requests, and drops all receiving packets. In this paper, a mechanism to detect the multiple black hole nodes has been proposed by modifying AODV protocol.