Shaikh Parvin B., Takale Sachin B.; International Journal of Advance Research, Ideas and Innovations in Technology © 2018, www.IJARIIT.com All Rights Reserved Page | 530 ISSN: 2454-132X Impact factor: 4.295 (Volume 4, Issue 4) Available online at: www.ijariit.com Improved LEACH routing protocol for wireless sensor networks Parvin B. Shaikh parvin786shaikh@gmail.com Sinhgad College of Engineering, Pune, Maharashtra Sachin B. Takale pb786shaikh@gmail.com Sinhgad College of Engineering, Pune, Maharashtra ABSTRACT In wireless sensor networks (WSNs), the present bunch based information accumulation procedure expends more vitality. Additionally, the secured information transmissions are essential for upgrading the information confirmation and secrecy. Keeping in mind the end goal to conquer these issues, in this review, in this paper, we provide detailed analysis on the relations between clustering and routing, and then propose a Low-energy adaptive clustering hierarchy (LEACH) protocol for reliable and efficient data collection in a large-scale wireless sensor network. LEACH adopts the back off timer and gradient routing to generate connected and efficient inter-cluster topology with the constraint of maximum transmission range. The relations between clustering and routing in LEACH are further exploited by theoretical and numerical analysis. The results show that the multi-hop routing in LEACH may lead to the unbalanced cluster head selection. Then the solution is provided to optimize the network lifetime by considering the gradient of one-hop neighbor nodes in the setting of back off timer. Theoretical analysis and simulation results prove the connectivity and efficiency of the network topology generated by LEACH. Keywords— WSN, Data aggregation, Clustering process, Data security, Packet delivery, Energy consumption, Packet drop, Transmission overhead 1. INTRODUCTION The wireless sensor network includes small and less cost sensing devices together with a wireless radio transceiver for examining the environment. It involves the data gathering and transmitting the information to one or more sink nodes. The main advantage of this network is that it does not require any infrastructure or external supply for data gathering. The main applications of WSN are wild habitat monitoring, forest fire detection, building safety monitoring, military surveillance and so on. The characteristics of WSN, which have resulted in challenging issues, are as follows: (i) Sensor nodes are exposed to maximum failures. (ii) Sensor nodes utilize the broadcast communication pattern and possess severe bandwidth restraint. (iii) Sensor nodes hold a scarce quantity of resources. Owing to the limited availability of resources, the amount of data transmission needs to be minimized. This, in turn, will enhance the network lifetime and bandwidth utilization. This can be achieved through data aggregation. The process of collecting the data from various sources followed by redundancy elimination thereby minimizing the transmission count is termed as data aggregation. This process leads to energy conservation. Moreover, the inherent redundancy in data gathered from the sensor node can be removed through the process of in-network data aggregation. This is mainly executed for extracting application-specific information. However, in a hostile environment, the aggregated data need to be protected from various attacks for attaining the data confidentiality, integrity, and authentication. Hence, security plays a major role in data aggregation [1]. 2. SECURITY REQUIREMENTS In the hostile environment of WSN, security is a key issue, whose requirements are discussed below: A. Data Confidentiality: The process of safeguarding the transmitted data from passive attacks corresponds to data confidentiality. The process of securing the data from the illegal user is the most challenging task. This can be solved by using an encryption technique such that only the intended user with appropriate key can unlock and read the data. B. Data Integrity: The compromised source nodes or aggregator nodes are prevented from altering the final aggregation value by data integrity. Since sensor nodes lack expensive tampering resistant hardware, they can easily be compromised. Moreover, this tampering-resistant hardware will not be reliable every time. A compromised node can modify, copy or discard messages[2].