Clone Detection in Wireless Sensor Networks using RSS and TOA

In a Wireless Sensor Network, the sensor nodes are vulnerable to capture and compromise. An adversary can easily analyze and capture the private information of a sensor network and are able to deploy a replica of the sensor nodes in the network at locations intelligently decided by the attacker. This is called Clone Attack, which is also called Replication Attack. A cloned node has legitimate information (codes and key materials), so it may participate in network operations in the same way as a non-compromised node. Clone Attack can cause a number of insidious attacks like disrupting communication, subverting, data aggregation, eavesdropping, deny of services on other sensor nodes and on the entire network itself. The whole network may become down or corrupted. So, it is necessary and important to detect and isolate the clone nodes in order to guarantee the security of a wireless sensor network. A new method based on the Received Signal Strength (RSS) value and Time Of Arrival (TOA) is proposed for detecting the clone attacks. RSS value of a node is the power of the received signal at the receiver. The RSS value of a signal is indirectly proportional to the distance between the two nodes. It is calculated based on the physical location of the sensor nodes by considering log normal shadowing. The clone nodes will be deployed at random locations decided by the adversary. It is challenging to find the location of a clone node. In the proposed method Time Of Arrival (TOA) is used to locate the clone nodes. TOA is defined as the time required by a signal to reach its destination. If an attacker node tries to communicate with a legitimate node in the network, the distance between them can be determined by using the TOA of the message. By finding the distance between any two nodes to the attacker, the clone nodes can be easily located. The x and y coordinates of the attackers can be determined.