An Intrusion Detection and Prevention System based on Timestamp and Hopcount Values for AODV Protocol in MANETs

Mobile Adhoc Networks (MANETs) are dynamic in nature. Any nodes can join and leave the network at any time. Hence any type of intruders can attack the communication at any time, especially the routing mechanism between the nodes. The base research by Dubey et. al [3] developed an intrusion detection and prevention system on AODV protocol. This research had a major drawback that it allowed a packet loss of minimum 5 to 6% which is quite high and also the methodology increased the energy consumption in network thereby reducing the lifetime. In this research, timestamp and hopcount analysis based black hole attack detection and prevention scheme is proposed that can be used to guard against black hole nodes in MANETs. The proposed scheme modifies the basic AODV protocol to add few extra headers in the RREQ and RREP packets to perform the intrusion detection and prevention. This packet passes on with every hop to reach the final node in path and all the checks for blackhole detection like hopcount check are performed at every hop. A path with hopcount going beyond max hopcount value is rejected. The proposed technique detects the prescence of both single and collaborative blackhole attacks. The blackhole detected is then added to the blacklist of packet and then each node in path updated for blacklist. This list is transmitted to every node with RREQ to broadcast the detection of a new blackhole node and then the malicious node gets isolated. The research concept was programmed in matlab language by defining a MANET simulator and it confirms the efficiency of proposed technique and also doesn't degrade the network lifetime.