Rau, A.V.Raghuvara, R.Shashimohan, V.Kulkami, M.2020-03-302020-03-3020102010 7th International Conference on Wireless and Optical Communications Networks, WOCN2010, 2010, Vol., , pp.-https://idr.nitk.ac.in/handle/123456789/7065Sensor networks, by their very nature, are vulnerable to network security threats, with Denial of Service by radio jamming being one of the most common. It is more useful to detect jamming reactively than to proactively avoid it. We describe a method of countering jamming wherein some nodes just outside the jammed region form groups and transmit their locations to the Base Station for localization. These nodes are downstream in the hop-count based gradient broadcast routing sense. We also estimate the exact position of the jammer using the centre of curvature method. Simulation results show that the error in estimation of the jammer location is as low as 1.03m, accurate enough for real-time response. �2010 IEEE.Book chapter