New Stream Cipher Designs

Volume 4986 of the series Lecture Notes in Computer Science pp 98-118

Sosemanuk, a Fast Software-Oriented Stream Cipher

  • Côme BerbainAffiliated withOrange Labs
  • , Olivier BilletAffiliated withOrange Labs
  • , Anne CanteautAffiliated withINRIA-Rocquencourt, projet CODES
  • , Nicolas CourtoisAffiliated withUniversity College of London
  • , Henri GilbertAffiliated withOrange Labs
  • , Louis GoubinAffiliated withUniversité de Versailles
  • , Aline GougetAffiliated withGemalto
  • , Louis GranboulanAffiliated withEADS
  • , Cédric LauradouxAffiliated withINRIA-Rocquencourt, projet CODES
    • , Marine MinierAffiliated withINSA de Lyon
    • , Thomas PorninAffiliated withCryptolog International
    • , Hervé SibertAffiliated withNXP Semiconductors

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Sosemanuk is a new synchronous software-oriented stream cipher, corresponding to Profile 1 of the ECRYPT call for stream cipher primitives. Its key length is variable between 128 and 256 bits. It accommodates a 128-bit initial value. Any key length is claimed to achieve 128-bit security. The Sosemanuk cipher uses both some basic design principles from the stream cipher SNOW 2.0 and some transformations derived from the block cipher SERPENT. Sosemanuk aims at improving SNOW 2.0 both from the security and from the efficiency points of view. Most notably, it uses a faster IV-setup procedure. It also requires a reduced amount of static data, yielding better performance on several architectures.