Cryptology ePrint Archive: Report 2007/380

X-FCSR: a new software oriented stream cipher based upon FCSRs

Francois Arnault, Thierry P. Berger, Cédric Lauradoux and Marine Minier

Abstract: Feedback with Carry Shift Registers (FCSRs) are a promising alternative to LFSRs in the design of stream cipher. The previous constructions based on FCSRs were dedicated to hardware applications. In this paper, we will describe X-FCSR a family of software oriented stream cipher using FCSRs. The core of the system is composed of two 256-bits FCSRs. We propose two versions: X-FCSR-128 and X-FCSR-256 which output respectively 128 and 256 bits at each iteration. We study the resistance of our design against several cryptanalyses. In this way, we achieve a high throughput and secure stream ciphers suitable for software applications (6.3 cycles/byte).

Category / Keywords: secret-key cryptography / stream cipher, FCSRs, software design, cryptanalysis

Publication Info: this paper was accepted as a short paper at Indocrypt 2007

Date: received 25 Sep 2007, last revised 26 Sep 2007

Contact author: marine minier at insa-lyon fr

Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation

Version: 20070927:043649 (All versions of this report)

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