A software-optimized encryption algorithm

P. Rogaway, D. Coppersmith

We describe a fast, software-oriented, encryption algorithm.
Computational cost on a 32-bit processor is about 5 elementary
machine instructions per byte of text. The cipher is a pseudorandom
function; under control of a key (first pre-processed into an
internal table) it stretches a short index into a much longer
pseudorandom string. This string can be used as a one-time pad.