Improving Quality of Service of trust based system against wormhole attack by multi-path routing method

The infrastructure of MANET is such that it does not have a fixed route path for routing and each nodes can individually acts as a base station. There is no centralized network. There are various attacks for which defend mechanism have been proposed by many researchers. Out of all such attacks wormhole attack poses a great threat as it has ability to grab the route more easily and is difficult to prevent. This paper basically focuses on wormhole attack and proposes an efficient detection and prevention method for this type of attack in AODV protocol using trust based mechanism. The method uses multi-paths for the path discovery process and thus provides greater path selection. The proposed method works by observing the routing path and the path that exceeds the threshold value are considered as wormhole link and the nodes on that link are identified as wormhole nodes. After detection of wormhole attack, for sending data packet from source to destination node we prefer multiple paths by which efficiency of network increases and packet delay as well as packet drop minimizes to great extent. Thus improves the Quality of Service of AODV protocol against wormhole attack.