Design of a cipher using cubic dynamic substitution box
Abstract
Nowadays, many organizations, companies, and an individual person share their data online through unreliable mediums ignoring that there are many hackers sitting outside to hack their data and misuse it. A cipher in cryptography is a set of predetermined procedures that may be used as a technique to achieve encryption and decryption. Cryptosystems are employed to demonstrate the security of private communication and information networks. Various permutation and substitution techniques are employed for this purpose. S-Box is in charge of the substitution procedure. Modern ciphers employ dynamic, key-dependent S-Box. In this work, we suggested a way for creating dynamic S-Boxes with strong cryptographic features. Techniques, such as bijectivity, nonlinearity, strict avalanche criteria, and linear probability, are used to assess the strength of the S-Box. After the creation of a dynamic S-Box, it is used in a novel cipher designed in this research thesis. Novel cipher consists of three phases such as key generation, encryption, and decryption. A different S-Box is generated using values taken from the key and employed in a cipher round to make things more difficult for the attackers.