A Novel Medical Image Signcryption Scheme Using TLTS and Henon Chaotic Map

In tele-medicine, images based on patient diagnostic tests and reports are usually required to broadcast securely so that recipient can receive them without any error. For the secure communication of sensitive medical data, there is a need of authenticated and unforgeable cryptosystem. In this paper, we propose a novel signcryption technique for medical images that fulfills the necessary security requirements of sensitive medical data during its communication. The design of novel medical image signcryption scheme is empowered by the combination strategy of hybrid cryptography. It employs a technique of public key cryptography furnished with elliptic curve cryptography for the generation of secret encryption key. The proposed scheme uses elliptic curve for signcryption purpose and chaotic maps for performing encryption of the medical images. It gives a combined mechanism of key exchange, digital signature and chaotic image encryption. Image encryption phase contains permutation and diffusion for pixel scrambling. The proposed image signcryption scheme provides confidentiality, authentication, integrity, unforgability, forward secrecy and non-repudiation. The use of chaos-based symmetric image encryption scheme shows good results for key space analysis, key sensitivity, correlation analysis, number of pixel change rate, unified average changing intensity, entropy analysis and histogram analysis. On the basis of the results obtained from all these analyses, we believe that the proposed medical image signcryption scheme is efficient and robust, providing good security for sensitive medical images.