A Data Security module based on Crypto and Steganography techniques

Abstract

Data security is one of such concern which cannot be avoided in today’s world. Protecting the sensitive data and personal information from unauthorised access and preventing it from being misused is important and can be done using various password protected software or systems, but is also possible to overcome these protecting software and systems through hacking and various other attacks. It is possible to store the sensitive data in an encrypted as well as secretly hidden way which will double the security level as first of all the attacker would have no idea where the secret data is hidden, even if in some way the attacker may find the secret data the it will be in an encrypted format which will be of no use to them. Therefore, it is necessary to introduces more than one level of security for data security. Hence in this paper one such approach has been proposed to use more than one technique for data security simultaneously namely cryptography and steganography, both of them are very popular techniques. The former is used to encrypt the data and the later is used to hide the data, together using both of them could help in increasing the security in a better way. This paper intends to improvise the technique of data security with a combination of the above two mentioned techniques and for a more secure approach, the data will be first encrypted using a key, and this key will be generated using the Diffie-Hellman key exchange algorithm and the key will be modified by key expansion, reduction and rotation techniques to increase the randomness for each round of encryption. Later this encrypted data will hidden into another image file, using the Least Significant bit steganography method by embedding encrypted data into lower order bits of the carrier image. In this paper the data hiding capacity is improved by increasing more than one least significant bits of the image and hence hence it will also reduce the number of clock cycles used for embedding and retrieving process. And the quality of the obtained output image will be benchmarked by calculating its PSNR (Peak signal to noise ratio) and MSE (Mean Square Error). The tools used for implementation are XILINX VIVADO, using verilog code for the proposed Architecture and MATLAB for image characterization and key generation.