Double layered Fridrich structure to conserve medical data privacy using quantum cryptosystem

Abstract

To handle pandemic situations like Corona, medical practitioners and researchers collaboratively will work together and transfer medical reports across the globe. Subsequently, it is important to preserve those reports from unauthorised access by providing utmost confidentiality, integrity and authentication. Quantum cryptography depends on quantum mechanics principles such as Heisenberg uncertainty and Photon polarisation, which aims in preventing the bootlegging of the encoded secret data in the quantum state. Quantum Algorithms are recently gaining wide attention among researcher's worldwide in optimising the protocols with adaptive learning and quadratic speed up compared to classical ones. Hence, a quantum assisted medical image encryption algorithm has been devised in protecting the shared reports in this paper. Initially, the medical images in Digital Imaging in Communication and Medicine (DICOM) format will be converted into Novel Enhanced Quantum Image Representation (NEQR) to survive in the quantum environment. Further, combined chaotic generators were utilised to generate random keys, ensuring a larger chaotic range and stability to withstand open communal channel attacks. Furthermore, double-layered Fridrich operations (Confusion and Diffusion) were carried out using the generated keys by adopting Quantum reversible gates. Finally, intra and inter bit permutations were conceded to provide a complete cryptic cipher image with uniform distribution of bits to resist the vulnerable attacks and enhance parallel data encryption procedure speed. Statistical and Differential attack analyses were estimated and compared with state of the art to justify the robustness of the proposed quantum cryptosystem. Also, complexity analysis has been derived to prove the proposed quantum algorithm's computational speedup compared to the classical part.