Wireless sensor networks (WSNs) refer to networks of spatially dispersed and dedicated sensors that monitor and record the physical conditions of the environment and forward the collected data to a central location. WSNs can measure environmental conditions such as temperature, sound, pollution levels, humidity, and wind. It usually comprise of gateways, sensors, and users in internet of things (IOT). IoT is the widely spreading technology, where the end user are directly allowed to access the desired sensor nodes to incur the data and even more they are permitted to broadcast commands to the nodes. Secure communication is a momentous concern in WSNs. The sensors are considered to be exceedingly resource constrained as they have limited memory, battery, and computation power. In real-life situations, these sensor nodes are used in a wide variety of applications, such as healthcare, environment monitoring, battlefield surveillance, agriculture and cropping, measurement of seismic activity, etc.