Design and Simulation of a Hybrid Hash-Based Algorithm to Mitigate Post-Quantum Cryptography Attacks in Internet of Medical Things

The classic methods of encryption and ciphering techniques have a major threat due to the rapid growth of quantum computing. This is particularly true for the Internet of Medical Things (IoMT) where sensitive patients’ data needs to be protected in terms of confidentiality, integrity, and authenticity. RSA and ECC serve as two examples of public key cryptographic algorithms that are highly vulnerable to quantum attacks especially the Shor’s and Grover’s algorithm. In the context of resource constrained IoMT systems, this thesis proposes a new hash-based hybrid cryptographic algorithm that is resilient to post-quantum cryptographic (PQC) attacks. In order to achieve resistance against quantum threats the proposed method uses hash-based digital signatures such as XMSS, SPHINCS+, or symmetric encryption like AES-256 with higher key sizes. In the Qiskit environment (Python, Anaconda Navigator, and Jupyter Notebook), Grover’s algorithm is modeled to simulate quantum threats. The proposed method is tested through quantum circuit analysis to evaluate their robustness. Our results will prove that the hybrid scheme, while remaining lightweight and suitable for real-time medical applications, significantly lowers the efficiency gains of quantum attacks. The proposed method will bridge the gap between the theoretical world of PQC and the practical world of IoMT networks, improving the long-term security and trust in critical healthcare systems.