A wireless sensor network consist of nodes containing sensors to monitors physical or environmental conditions, such as temperature, sound, pressure etc. Each node in a sensor network consist of a transceiver unit, a processing unit, a power unit, a small micro-controller and a battery which is used as the energy source. Generally the processing unit is associated with a small storage unit and manages the procedures that make the code collaborate with the other nodes to carry out the assigned tasks.
The transceiver unit connects the node to the network. Power unit is an important component of a node and it may be supported by power generator such as solar cells. Sensor nodes are equipped with very limited computational power and energy resources. The WSN consist of hundreds or thousands of nodes that are scattered in an area called as sensor field. The nodes sense data and forward the same to the outside world via the sink node or the base station. The base station or the sink node is responsible for receiving data from the nodes present in the network and processing them for sending the data to the outside world.
The sensor nodes collect data and sent the data to their neighboring nodes in single hope. The neighboring nodes in turn send the data to the nodes located in single hope distance. In this way the data is transmitted to the sink node. The data ultimately reaches the user via the internet or satellite. Nodes in a WSN are deployed in an open field and thereby they remain unattended and are prone to attack by adversaries. One such attack is known as jamming attack in which the adversary blocks the radio communication of one or more nodes which are with in the sensing range of the adversary by capturing a particular frequency.
In such a situation, the jammed sensor nodes which were using the particular frequency for communication will not be able to communicate further until the adversary leaves that particular frequency. Therefore with this attack the adversary can stop the communication among the sensor nodes resulting in data losses.