IOSR Journal of Electronics and Communication Engineering (IOSR-JECE) e-ISSN: 2278-2834,p- ISSN: 2278-8735.Volume 12, Issue 3, Ver. IV (May - June 2017), PP 47-50 www.iosrjournals.org DOI: 10.9790/2834-1203044750 www.iosrjournals.org 47 | Page Development of Energy Efficient CoAP Based WSN Time Synchronization System Using NS2 Sukanya Padave 1 ,Prof. Gayatri S. Ambadkar 2 , 1 (Student NMIET, Talegaon, Pune, Maharashtra, India) 2 (Assistant Professor, E&TC, NMIET, Talegaon, Pune, Maharashtra, India) Abstract: This paper aims to develop energy efficient solution for transmission in WSN. Sensors works on battery powered cells which is difficult to replace again and again due to excessive use of power while being active all the time. For time synchronization in the transmission of the data from several nodes to its intended destination CoAP architecture is developed using NS2 along with that, developed architecture has been evaluated in the form of energy efficient model called as EECoAP protocol. Keywords: Time Synchronization, WSN, CoAP (Constrained Application Protocol), EECoAP (Energy Efficient CoAP). I. Introduction Wireless technology is developing to higher level, as use of wireless channel to communicate over long distance is increasing day by day which is making it one of the most excellent and desirable development in communication technology. Being heart of any control or monitoring method, wireless sensor plays a vital role in transferring sensed data over the distance more quickly. Main task of the sensor node is depends on its configured threshold value to sense particular data where it has been installed to observe operation of application field. Monitoring any application keeps sensors active all the time which will expend more power than the capacity it has in its battery powered cells. Motivation behind developing algorithm is to save power i.e energy expenditure in WSN, we can call this algorithm as EECoAP(Energy Efficient Constrained Application Protocol) as mechanism to reduce the energy expenditure is developed for CoAP protocol, so the developed algorithm is labeled as Energy Efficient CoAP. Fig.1 is the explanation how nodes sends data to destination decision making device through home gateway. Fig.1. Connection of wireless sensors to send data. II. Related Study Many researchers were working to find solution for reducing energy expenditure in WSN. As data transferring through internet that is with the help of IP and Non-IP devices energy saving is the prime important characteristic in today’s development. Energy expenditure using Position Responsive routing Protocol with the help of GPS system can be reduce to much higher level[1]. Central node in WSN has capability to keep status of the node with the help of which path can be selected to reduce energy consumption in transferring the data[2]. Various energy resourceful methods like LEACH, HEED, DECA etc are discussed by[3]. How clustering method of WSN can help to reduce energy expenditure is explained in[4][10]. Maxwell equation can increase sensors life with the help of efficient routing protocol[2]. Network lifespan has been increased to good level by using rigorous approach in routing[5]. Fig.2 explains important sections in sensor node it comprises of sensing device which sends value sensed or recorded with the help of transducers i.e it accepts physical input signal and sends electrical output to processor and controller unit which is responsible to take appropriate action with the help of trans-receiver section all these major components works on non rechargeable batteries.