Wormhole Attack in Wireless Sensor Network

In multi hop wireless systems, such as wireless sensor networks, mobile ad hoc network, security is an important factor. It becomes more critical issue when we transmit important data between nodes. There are a lot of attacks available in wireless sensor network or mobile ad hoc network. In our paper we are going to discuss about a particularly devastating attack, known as the wormhole attack. In wormhole attack, an attacker forms two or more malicious nodes in the network at different locations. These nodes are connected with the help of low latency link. As a result of this way two or more malicious nodes create a higher level virtual tunnel in the network. This virtual tunnel is used for sending the packets between the end points of tunnel. Whenever transmission starts between a source to destination, adversary try to record transmitted packets at one location in the network and tunnels all captured packets to another location. The wormhole attack is possible even if the attacker has not compromised with any hosts and even if all communication provides authenticity and confidentiality. The wormhole attack can form a serious threat in wireless networks, especially against many ad hoc network routing protocols and location-based wireless security systems. In this paper, we analyze the nature of wormhole attack in ad hoc and wireless sensor networks and existing methods of the defending mechanism to detect wormhole attacks without require any specialized hardware.