TWO STAGE SECURE MEDICAL DATA TRANSMISSION FOR IOT BASED E-HEALTH APPLICATION

Abstract

Encryption cryptography is the process of encoding messages in a way that hackers cannot read it, but that can be authorized personnel. The two main algorithms used for data encryption in this work are the Advanced Encryption Standard (AES) and the Rivest-Shamir-Adleman (RSA) algorithm. AES is a symmetric cipher where the same key is used on both sides. It has a fixed message block size of 128 bits of text (plain or cipher), and keys of length 128,192, or 256 bits. When longer messages are sent, they are divided into 128-bit blocks. Apparently, longer keys make the cipher more difficult to break, but also enforce a longer encrypt and decrypt process. On the contrary, the RSA is a public key algorithm, which widely used in business and personal communication sectors. It has the advantage of having a variable key size ranging from (2-2048) bits. Due to the significant advancement of the internet of things (IoT) in the healthcare sector, the security and the integrity of the medical data became big challenges for healthcare services applications. This paper proposes a hybrid security model for securing the diagnostic text data in medical images. The proposed model is developed through integrating either 2D Discrete Wavelet Transform 1 Level (2D-DWT-1L) or 2D Discrete Wavelet Transform 2 Level (2D-DWT-2L) steganography technique with a proposed hybrid encryption scheme. The proposed hybrid encryption schema is built using a combination of Advanced Encryption Standard (AES), and Rivest, Shamir, and Adleman (RSA) algorithms. The proposed model starts by encrypting the secret data; then it hides the result in a cover image using 2D-DWT-1L or 2D-DWT-2L. Both color and gray-scale images are used as cover images to conceal different text sizes.