S S symmetry Article A Secure and Efficient Lightweight Symmetric Encryption Scheme for Transfer of Text Files between Embedded IoT Devices Sreeja Rajesh 1, Varghese Paul 2, Varun G. Menon 3,* and Mohammad R. Khosravi 4 1 Department of Computer Science, Bharathiar University, Coimbatore 641046, Tamil Nadu, India;
[email protected] 2 Department of Information Technology, Cochin University of Science and Technology, Ernakulam 682022, Kerala, India;
[email protected] 3 Department of Computer Science and Engineering, SCMS School of Engineering and Technology, Ernakulam 683582, Kerala, India 4 Department of Electrical and Electronic Engineering, Shiraz University of Technology, Shiraz 71555-313, Iran;
[email protected] * Correspondence:
[email protected]; Tel.: +918714504684 Received: 29 January 2019; Accepted: 20 February 2019; Published: 24 February 2019 Abstract: Recent advancements in wireless technology have created an exponential rise in the number of connected devices leading to the internet of things (IoT) revolution. Large amounts of data are captured, processed and transmitted through the network by these embedded devices. Security of the transmitted data is a major area of concern in IoT networks. Numerous encryption algorithms have been proposed in these years to ensure security of transmitted data through the IoT network. Tiny encryption algorithm (TEA) is the most attractive among all, with its lower memory utilization and ease of implementation on both hardware and software scales. But one of the major issues of TEA and its numerous developed versions is the usage of the same key through all rounds of encryption, which yields a reduced security evident from the avalanche effect of the algorithm.