Discrete Mathematics & Theoretical Computer Science (Jan 2011)

NOCAS : A Nonlinear Cellular Automata Based Stream Cipher

  • Sandip Karmakar,
  • Dipanwita Roy Chowdhury

DOI
https://doi.org/10.46298/dmtcs.2970
Journal volume & issue
Vol. DMTCS Proceedings vol. AP,..., no. Proceedings

Abstract

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LFSR and NFSR are the basic building blocks in almost all the state of the art stream ciphers like Trivium and Grain-128. However, a number of attacks are mounted on these type of ciphers. Cellular Automata (CA) has recently been chosen as a suitable structure for crypto-primitives. In this work, a stream cipher is presented based on hybrid CA. The stream cipher takes 128 bit key and 128 bit initialization vector (IV) as input. It is designed to produce $\mathrm{2^{128}}$ random keystream bits and initialization phase is made faster 4 times than that of Grain-128. We also analyze the cryptographic strength of this cipher. Finally, the proposed cipher is shown to be resistant against known existing attacks.

Keywords