Avoidance of Black Hole and Gray Hole Attack in MANET using Hash Function based

Abstract

MANET is mobile ad-hoc network having less number of infrastructural elements. Various mobile nodes inter communicate to each other through wireless links. As there is no central controller which can control the access permission. Any node can be the part of the communication at any time. While doing this there can be any number of malicious nodes. These malicious nodes behaves as they are legitimate node and contributes to the process of building the path. but the path build through them can be wrong. In such situation the packets transmitted through them will be either misrouted and being dropped. In such situation some authentic procedure is required, which can control the access permissions. Timely these nodes should be identified and removed. In current research hash based technique is used. while communicating two nodes shares there keys amongst themselves. If certain node will not be able to share the hash value. Will be declared malicious. That means without malicious node the network performance will be upgraded automatically. Under current research we have checked the performance with different parameters like end to end delay, through put, success rate, packet delivery ratio. All these parameters has shown certain amount of improvement over to the previous technique.