A Lightweight Hybrid Encryption and Blockchain-Inspired Secure Storage Model for IOMT Data

Abstract

The Internet of Medical Things (IoMT) enables continuous patient monitoring and intelligent healthcare services, but it also introduces serious challenges related to the confidentiality and integrity of sensitive medical data stored in distributed environments. Due to their limited computational and energy resources, IoMT devices require lightweight yet robust security mechanisms that can protect data without incurring excessive overhead. This paper presents a lightweight IoMT data storage framework that combines hybrid encryption with a blockchain-inspired integrity assurance mechanism. The proposed approach employs ChaCha20 for efficient data encryption at IoMT devices, AES for secure symmetric key protection at gateway nodes, and Elliptic Curve Cryptography (ECC) for secure key exchange and mutual authentication. To ensure data integrity and tamper resistance in cloud storage, a hash-linked storage structure integrated with Merkle tree verification is designed, drawing inspiration from blockchain technology without deploying a full blockchain network. A Python-based prototype implementation is developed to evaluate the performance of the framework in terms of encryption latency, throughput, and integrity verification overhead. Experimental results demonstrate that the proposed scheme achieves strong security guarantees while maintaining low computational cost, making it well suited for resource-constrained IoMT environments. Overall, the proposed model offers a practical and scalable solution for securing healthcare data storage in next-generation IoMT systems.