SNOW - a new stream cipher

Abstract

In this paper a new word-oriented stream cipher, called SNOW, is proposed. The design of the cipher is quite simple, consisting of a linear feedback shift register, feeding a finite state machine. The design goals of producing a stream cipher significantly faster than AES, with significantly lower implementation costs in hardware, and a security level similar to AES is currently met. Our fastest C implementation requires under 1 clock cycle per running key bit. The best attacks are generic attacks like an exhaustive key search attack