Securing resource-constrained devices such as Radio Frequency Identification (RFID) tags and wireless sensors in Internet of Things (IoT) environments is a growing challenge due to the limited computational power budget, memory, and processing capabilities available on such devices. Classical encryption algorithms such as Advanced Encryption Standard (AES) and RSA are considered computationally expensive in these settings, making lightweight block ciphers a necessary alternative. Among the most prominent candidates are three algorithms namely, Present, Skinny, and Gift, each representing a distinct generation in the evolution of lightweight cryptography. Selecting the most suitable cipher, however, requires careful balance of the trade-offs between performance, security, and energy efficiency. In this paper, we evaluate these three ciphers through software-based experiments implemented in C, measuring execution time, avalanche effect, estimated energy consumption, and a composite security score that combines theoretical cryptanalytic resistance with experimental diffusion results. Furthermore, a refined version Gift-128 algorithm based on a precomputed round-key table is proposed to improve its computational efficiency while preserving its cryptographic properties. Experimental results demonstrate the effectiveness of the proposed enhancement of Gift-128 algorithm.
