Reducing Multi-Secret Sharing Problem to Sharing a Single Secret Based on Cellular Automata

The aim of a secret sharing scheme is to share a secret among a group of participants in such a way that while authorized subsets of participants are able to recover the secret, non-authorized subsets of them obtain no information about it. Multi-secret sharing is the natural generalization of secret sharing for situations in which the simultaneous protection of more than one secret is required. However, there exist some secret sharing schemes for which there are no secure or efficient multi-secret sharing counterparts. In this paper, using cellular automata, an efficient general method is proposed to reduce the problem of sharing k secrets (all assigned with the same access structure and needed to be reconstructed at once) under a certain secret sharing scheme (S), to the problem of sharing one secret under S such that none of the properties of S are violated. Using the proposed approach, any secret sharing scheme can be converted to a multi-secret sharing scheme. We provide examples to show the applicability of the proposed approach

Robust Image Encryption Based on Balanced Cellular Automaton and Pixel Separation

The purpose of image encryption is to protect content from unauthorized access. Image encryption is usually done by pixel scrambling and confusion, so process is possible to reverse only by knowing secret information. In this paper we introduce a new method for digital image encryption, based on a 2D cellular automaton and pixel separation. Novelty in the proposed method lies in the application of the balanced 2D cellular automata with extended Moore neighborhood separately on each level of pseudorandom key-image. This process extends key space several times when compared to the previous methods. Furthermore, pixel separation is introduced to define operation for each pixel of the source image. Thanks to pixel separation, decryption process is more difficult to conduct without knowing secret information. Moreover, encryption is robust against different statistical attacks and analysis, does not affect image quality and can cope with loss of encrypted image content