A novel approach for mitigating route request flooding attack in MANET

Mobile ad-hoc network (MANET) is a temporary network in which the main requirement for establishing the communication path among nodes is that the nodes should be cooperative. However, in the presence of malicious node, the MANET’s routing protocol such as AODV is vulnerable to different types of flooding attacks. The flooding attack can be continuous or selective. In the available literature, although many researchers have analyzed the network under continuous flooding attack but they have not focussed on selective flooding attack in which an attacker can sometimes behave as a normal and sometimes behave as a malicious. Most of the existing schemes use constant threshold value which lead to a false positive problem in the network. In order to address this issue, a new mechanism called as Mitigating Flooding Attack Mechanism is proposed which is based on a dynamic threshold value and consists of three phases. It makes use of several special nodes called as Flooding-Intrusion Detection System (F-IDS) that are deployed in MANETs in order to detect and prevent flooding attack. The F-IDS nodes are set in promiscuous in order to monitor the behaviour of the node. The simulation results show that the proposed mechanism improves network performance metrics in terms of PDR, throughput and reduces the routing overhead as well as normalized routing load.