International Journal of Modern Engineering Research (IJMER)
Wireless Sensor Networks (WSNs) consisting of large numbers of low-power and low-cost wireless nodes, have recently been employed in many applications: military surveillance, disaster response and medical care among others. The inherent nature of sensor networks such as unattended operation, battery-powered nodes, and harsh environments pose major challenges. One of the challenges is to ensure that the network is always connected. The connectivity of the sensor network can easily be disrupted due to unpredictable wireless channels, early depletion of node's energy, and physical tampering by hostile users.