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Out of the S-Box Encryption and Decryption

Substitution boxes (S-boxes) have been extensively used in almost all conventional cryptographic algorithms, such as data encryption standard (DES) and advanced encryption standard (AES). S-boxes are the only non-linear components in these cryptosystems. The strength of cryptographic algorithms is determined by these non-linear S-boxes, so the construction of cryptographically strong S-boxes is important in the design of secure cryptosystems. S-boxes are usually designed using the non-linearity criteria inspired by linear and differential cryptanalysis. It is the objective of most designs to keep the maximum differential and linear approximation probabilities of an S-box as small as possible. Recently, chaos has attracted significant attention of researchers for the design of new cryptosystems. Many methods have been proposed to design S-boxes based on chaos. The present study have come out with a novel method of constructing cryptographically strong S-boxes based on the mixing property of chaotic dynamical systems, where the linear approximation probability of the S-Box constructed is lower than that of the AES S-Box.

www.platcomventures.com

The inventors would like to speak to companies interested in licensing this technology.

E: info@platcomventures.com T: +603 8319 3116

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A substitution plays a central role in cryptographic algorithms, and for this reason an efficient method for designing S-Boxes based on chaotic maps have been applied, which is based on the mixing property of piecewise linear chaotic maps. The S-Box that is constructed has low differential and linear approximation probabilities, and more secured against differential and linear cryptanalysis compared to recently proposed chaotic S-boxes. As chaos attracts significant attention of researches for the design of new cryptosystems, this new method opens new markets in cellular, medical, personal and enterprise level applications.

The market size for S-Box is very wide as it covers symmetric encryption in all its aspects, for example Telecom Industries (cellular, satellite, Wi-Fi), health (medical image), information security in military and multimedia (pay TV, image encryption), etc. The present invention aims to target image encryption and communication for medical, personal and enterprise level applications. With the growing market of end-to-end digital media transmission over internet, the present invention will be able to meet the demand for their security and private viewing. The S-Box will be a software IP that encryption system designers would buy and integrate with their multimedia systems like those on smartphones, personal computers, laptops, cameras, etc. It can be deployed in both forms as a software application programming interface (API) or a hardware component.

© 2014 PlaTCOM Ventures. All rights reserved.

S-Box is copyrighted.

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• The proposed S-Box is designed utilising chaos and difference distribution table (DDT)

• It is a process to design a unique S-Box in that it uses DDT as an integral component to optimize an S-box.

• Presently, DDT is only considered as a tool to measure differential approximation probability which helps in differential cryptanalysis

• DDT has never been considered to minimise differential probability of an S-Box at the time of its design

• The invention achieves lowest differential probabilities as compared to other recently proposed state-of-the-art S-Boxes

• Accordingly, it gives rise to better image encryption than those in the literature.