Study and Analysis New Algorithm for Effective Cryptographic in Telemedicine Purposes Using Hill Cipher after Modification
Firas Shawkat Hamid1, Thakwan Akram Jawad2, Ersun Iscioglu3
1Dr. Firas Shawkat Hamid,  Head of Department of Computers Systems in Technical Institute, Ministry Of higher Education and Scientific Research, Iraq.
2Thakwan Akram Jawad,  Engineer in Engineering College, Mosul University, Iraq.
3Assist. Prof. Ersun Iscioglu,  Head of Department of Computer and Instructional Technology Education, Eastern Mediterranean, University, Iraq.
Manuscript received on January 25, 2014. | Revised Manuscript received on February 13, 2014. | Manuscript published on February 28, 2014. | PP: 99-109  | Volume-3, Issue-3, February 2014. | Retrieval Number:  C2593023314/2013©BEIESP

Open Access | Ethics and Policies | Cite
© The Authors. Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC BY-NC-ND license (

Abstract: Nowadays, digital exchanges of medical images are frequently used throughout the world in a fraction of a second via the Internet. These data can be read or modified during their transmission via a non-controlled channel. Therefore, it becomes very important to protect this private information against unauthorized viewers by using cryptography. This work presents a cryptography method that uses the properties of Hill Cipher algorithm for medical images. The fast evolution of digital data exchange, security information becomes much important in data storage and transmission. Image, which covers the highest percentage of the multimedia data, its protection is very important. This can be achieved by image encryption. As the use of digital techniques for transmitting and storing image are increasing, it becomes an important issue that how to protect the confidentiality, integrity, and authenticity of image. Each type of data has its own features; therefore various techniques which are discovered from time to time to encrypt the images should be used to protect confidential image data from unauthorized access and to make images more secure. Image encryption techniques scrambled the pixels of the image and decrease the correlation among the pixels, so that we will get lower correlation among the pixel and get the encrypted image. Encryption is used to securely transmit data in open networks. The Hill cipher algorithm is one of the symmetric key algorithms that have several advantages in data encryption. However, a main drawback of this algorithm is that it encrypts identical plaintext blocks to identical ciphertext blocks and cannot encrypt images that contain large areas of a single color. Thus, it does not hide all features of the image, which reveals patterns in the plaintext. Moreover, it can be easily broken with a known plaintext attack revealing weak security. This paper presents a variant of the Hill cipher that overcomes these disadvantages, has been proposed new encryption algorithm using modify the existing Hill cipher to decrease the susceptibility to known plaintext attacks. This is achieved by randomizing the information locations for the whole image. So, even if the attacker can guess the key, the decryption still give false information. Both of Hill image cipher and the proposed modification on it (termed M Hill in this paper) are suitable for all images block encryption. The proposed algorithm is carried out via two approaches that is through comparative study and statistical analysis. Results from this comparative have shown that Hill cipher with randomized approach has greatest the Number of Pixels Changed Rate (NPCR) and the Unified Averaged Changed Intensity (UACI) value are two most common
Keywords: NPCR, UACI.