A Lightweight Cipher for Balancing Security Trade-Off in Smart Healthcare Application

IoT is a dynamic, emerging sector characterized by using existing Internet infrastructure to connect devices and data centers worldwide. The internet of healthcare things (IoHT) is a subclass of IoT that includes high-tech medical equipment that plays a crucial role in data monitoring, processing, storage, and transfer. It has novel challenges in data security. Several cryptographic techniques have been devised to safeguard the system against data misuse, alteration, and node tempering. Such cryptographic algorithms are inadequate because of the device's diminutive size, limited computing power, memory, and power resources. A lightweight cryptographic scheme based on symmetric cryptosystems powered by the Feistel structure is required to secure such a system. A lightweight cryptosystem is proposed in this paper for the security of the e-healthcare system. The proposed algorithm encompasses a compact S-box function, less round and addition substitution, and an XOR operation to generate encrypted information from plaintext. Additionally, a secure authentication mechanism based on the previously mentioned method is suggested for secure communication in the healthcare system. The cryptanalysis process and result state that our proposed system resists several cryptanalytic attacks which include brute force, avalanche effect, linear cryptanalysis, and biclique attack when compared with standard AES algorithm.