International Journal of Research Review in Engineering Science & Technology (IJRREST)
Sensor network consists of tiny sensors and actuators with general purpose computing elements to cooperatively monitor physical or environmental conditions such as temperature, pressure, etc. Sensor networks have a huge application in fields which includes habitat monitoring, object tracking, fire detection, land slide detection and traffic monitoring. Depending on the resources limitations and used applications of WSNs (Wireless Sensor Networks). Security is very important and big challenge in WSNs. The broadcast nature of wireless sensor network is the reason why wireless sensor networks are susceptible to security attacks. In various network attacks, the Distributed Denial of Service attack (DDoS) attack is a severe threat. In order to deal with this kind of attack in time, it is necessary to establish a special type of defense system to change strategy dynamically against attacks.