DT-AODV: a dynamic threshold protocol against black-hole attack in MANET

In wireless networks, Mobile Ad-hoc Network (MANET) is an emerging and pervasive technology that consists of autonomous mobile nodes. Each node in the network can join freely or randomly leave the network. The mobile nodes interact with other nodes through intermediate nodes without needing any fixed infrastructure. It is assumed in this network that the intermediate nodes always help in finding the destination node by rebroadcasting the request packet sent by the source node if the destination is not available in the routing table. However, in a real environment, there can be some dishonest node in the network that does not help in finding the optimal path for the destinations and sends the false route reply about having the shortest path for the destination nodes with the maximum destination sequence number. The false route reply packet sent by the liar node attracts the data traffic which ultimately does the packet dropping in the network. Such type of malicious activity in this network is generally referred as a black-hole attack which is an active attack and results in the degradation of network performance. In this paper, a Dynamic Threshold-Ad-hoc On-Demand Distance Vector (DT-AODV) protocol is proposed which is based on a dynamic threshold value. The NS-2 simulator is used for evaluating the performance of various protocols and the results show that DT-AODV has good performance as compared with existing state of art MBDP-AODV protocol under the black-hole attack with 99.10% packet delivery rate, 20.01 kbps throughput, 1750 routing overhead, and 0.51 normalized routing load.