JWCN_V1_N4_RP2 Gaurav Bathla Journal On Wireless Communication Networks 2320 - 2351 1 4 12 23 Clustering, Sensor nodes, Energy efficiency, Homogeneous, Heterogeneity, Stability, WSN Potential use of wireless sensor networks (WSNs) can be seen in various fields like disaster management, battle field surveillance and border security surveillance since last few years. In such applications, a large number of sensor nodes are deployed, which are often unattended and work autonomously. Clustering is a key technique used to extend the lifetime of a sensor network by reducing energy consumption. It can also increase network scalability. Researchers in all fields of wireless sensor network believe that nodes are homogeneous, but some nodes may be of different energy to prolong the lifetime of a WSN and its reliability. In this paper an attempt is made to calculate energy required for all the nodes to be placed in the network in the same structure as was defined under MSMTP protocol in bottom up fashion i.e. energy of all nodes is initialized to zero & after each round transmission & receiving energy required is added to energy of each node. After completing certain number of rounds required energy of each node can be deduced. January - March 2013 Copyright © 2013 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=2189