The great potential of Wireless Sensor Network is being seen in industrial, consumer and commercial application. The wireless technology is becoming one of the most prominent areas of research. With the development of network and communication technology, the WSN has solved the inconvenience into people’s lives. WSN has good functions of data collection, transmission, and processing. In the older technology there was a shortcoming of average packet time delay, large power dissipation, less efficient reception of packets, large propagation delay, low speed communication. Besides there were other limitations like limited battery life time nodes incapability of data aggregation, processing, storing and then passing it to the base station accordingly.. As in the earlier Technologies WSN node based leach protocol could not provide the above necessary requirements for the system to operate under well adverse environmental situations. In this dissertation, we have used a ZigBee protocol in WSN system for ensuring that the nodes may operate for a longer period of time, reducing packet time delay, establishment of a re-linking algorithm and provides an efficient reception packet and sufficient throughput The advantage of ZigBee Technology is that it covers a range of 1-100m For comparison purposes, we have taken the oldest technology i.e SEP .To allow different systems to work together, standards are needed. ZigBee/IEEE 802.15.4 protocols are developed for this purpose. Moreover, ZigBee protocol in WSN has resulted in the low power consumption, enhancement of life time of battery reduced average packet time delay less power dissipation improved an efficient reception of packets, reduced propagation delay, high speed communication among wireless communication devices. On comparing the results of both that is the previous work over which work has been done earlier and present work it has been observed that modified system performs better.