A Novel Mutual Authentication Scheme using Non-Expansion Visual Cryptography in Reversible Style

The growing possibilities of modern communications require a special means of confidential and intellectual property protection against unauthorized access and use. Cryptography provides important tools for the protection of information and they are used in many aspects of computer security. This paper makes use of encrypted secret sharing to increases the security level of hidden data and to provide Mutual Authentication of the users. The visual cryptography scheme is a perfect secure method that encrypts a secret image by breaking it into shadow images. A distinctive property of visual cryptography scheme is that one can visually, without computation, decode the secret by superimposing shadow images. The property of visual secret sharing in reversible style provides more security. This method not only can fast decode without causing pixel expansion but also increase the secret-hiding ratio. Random-Grid Algorithm is used to create secret shares without pixel expansion. This paper extends the capabilities of the Visual Cryptography as a mere secret sharing technique to a Novel Mutual Authentication provider. If one stacks two transparencies(shares) together straightforwardly, a secret image will appear. Stacking two transparencies after reversing one of the transparencies, another secret image will unveil. An attempt is made to provide two transparency three-way mutual authentication by using Visual cryptography in the reversible style.