IJSRSET207554 | Received : 05 April 2019 | Accepted : 25 April 2019 | March-April -2019 [ 6 (2) : 698-705 ] © 2019 IJSRSET | Volume 6 | Issue 2 | Print ISSN: 2395-1990 | Online ISSN : 2394-4099 Themed Section : Engineering and Technology DOI : 10.32628/IJSRSET 698 Review : Secure energy-efficient IoT based wireless sensor networks: Findings and Challenges Dr. J. Keziya Rani 1 , M. Sri Lakshmi 2 1 Assistant Professor, Department of Computer Science & Technology, S.K University, Anantapuramu, Andhra Pradesh, India 2 Research Scholar, Department of Computer Science & Technology, S.K University, Anantapuramu, Andhra Pradesh, India ABSTRACT Wireless sensor networks (WSNs) have demonstrated research and developmental interests in numerous fields, like communication, agriculture, industry, smart health, monitoring, and surveillance. Sensor nodes are treated as smart devices and widely used to gather and forward sensed information. However, besides intrinsic constraints on sensor nodes, they are vulnerable to a variety of security threats. This paper reviews the findings and Research challenges on secure energy-efficient IoT based wireless sensor networks. Keywords : Wireless Sensor Networks, Internet of Things, Sensor nodes, Security. I. INTRODUCTION In various domains, the technology of wireless sensor network (WSN) [1–3] has been used in an efficient way to improve network performances. The main reason to uses different sensors in the environmental field due to their manageable and easy configuration setup [4]. Additionally, the sensor nodes operate autonomously and construct the network infrastructure in an ad-hoc manner. In such infrastructure, nodes have not a stable network topology, and they can join the more suitable neighbor for data transmission based on some factors. The sensor nodes sense the observing data and forward towards BS with the help of some gateway and cluster heads. These cluster heads have a role of aggregating the received data packets and relay towards BS. The cluster heads effectively construct a single-hop or multi-hop path to BS and work as a focal point in entire data transmission. Furthermore, the cluster heads store the received data in its memory and follow the store and forward mechanism. The end-users access the centralized BS via the Internet or different web-based applications to retrieve the required observing data. During data transmission, the deployed sensors can be static or mobile. The static sensors are also referred to as non-adaptive and their constructed routing tables are fixed. While on the other hand, the routing tables of mobile sensors are dynamic and frequently updated when any change incurs in the network topology. The static routing solutions are more secure when compared to dynamic routing; however, the solutions that are based on the static algorithms are not appropriate for large regions and network scalability In recent years, the technology of IoT has been merged a lot with other fields to improved communication in terms of network throughput, resource utilization, and load distribution [7–9]. In IoT, many physical objects are attached to convert the information while using the