Implementation of Rivest Shamir Adleman Cryptographic Algorithms and Techniques of Steganography First of File for Message Security

Abstract

Accessing data by an unauthorized person often happens these days. Addressing this case, the techniques of cryptography and steganography was necessary. The science of cryptography use randomizes/disguise the data, whereas the science of steganography to hide data in a way. The cryptographic algorithms to be used is the Rivest Shamir Adleman (RSA) which utilizes two prime numbers to generate a public key and private key. To further enhance the security of message, the algorithm has combined with the First of File (FoF) as steganography techniques. The technique First of File (FoF) works by inserting a message at the beginning of the file image horizontally to produce a stego image that will extract to get the previous ciphertext. Then the ciphertext decrypted to be returned to the original message. By using FoF, in the cover image with large pixel size, the insertion process with FoF is entirely invisible, so the stego image and original image cannot be distinguished, whereas in small pixels there is a black line above the image. A combination of RSA and the FOF will increase data security because when a message has scrambled into a ciphertext and the ciphertext will be inserted into the image file.