1433 Copyright © 2016, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 62 DOI: 10.4018/978-1-4666-8751-6.ch062 Energy Consumption Analysis of Secure and Clustered Wireless Sensor Network ABSTRACT Due to limited energy resources, diferent design strategies have been proposed in order to achieve better energy efciency in wireless sensor networks, and organizing sensor nodes into clusters and data aggregation are among such solutions. In this work, secure communication protocol is added to clustered wireless sensor network. Security is a very important requirement that keeps the overall system usable and reliable by protecting the information in the network from attackers. The proposed and implemented AES block cipher provides confdentiality to the communication between nodes and base station. The energy efciency of LEACH clustered network and with added security is analyzed in detail. In LEACH clustering along with the implemented data aggregation technique 48% energy has been saved compared to not clustered and no aggregation network. The energy consumption overhead of the AES-based security is 9.14%. The implementation is done in Contiki and the simulation is carried out in Cooja emulator using sky motes. 1. INTRODUCTION Wireless sensor networks are proliferating into our everyday life in the form of differ- ent applications, such as eHealth (Ho, ym., 2009; Honeine;Mourad;Kallas;Snoussi;Amo ud;& Francis, 2011; Singh;Tiwary;Hoon-Jae;& Chung, 2009), environment and infrastructure monitoring (Yunseop;Evans;& Iversen, 2008), home automation(Langhammer & Kays, 2012; Tudose, ym., 2011; Zhang;Song;Wang;& Meng, 2011), traffic control (Laisheng;Xiaohong;Zhen gxia;Bing;& Pengzhi, 2009; Zou;Yang;& Cao, 2009), agriculture (Vijayakumar & Rosario, 2011; Zhang Y., 2011)[29-30], and manufact uring(Bertocco;Gamba;Sona;& Vitturi, 2008; Ashim Pokharel University of Turku, Finland Ethiopia Nigussie University of Turku, Finland