Mobile Ad-hoc Network (MANETs) is a temporary wireless network, which is self-configuring in which nodes moves freely and continuously. It consists of a collection of wireless mobile nodes which dynamically exchange data among themselves without the reliance on a fixed base station or a wired resolution network. Due to its mobility and self-routing effective nature, there are many deficiencies in its security. Various security threats show their impact at different layer. Wormhole attack is a network layer attack observed in MANET, which completely disrupts the communication channel. Among all of security thread worm hole is consider to be a very serious security thread over MANET. In wormhole two selfish node which is geographically very far away to each other, makes tunnel between each other to cover their actual location and try to believe that they are true neighbours and makes conversation through the wormhole tunnel. The goal of this paper to study wormhole attack, some detection methods and different techniques to prevent network from these attacks.

MANET wormhole attack