ARCFour information
ARCFour is a stream cipher that is fully compatible with the RC4TM cipher. Unlike a block cipher that works on blocks of bytes, a stream cipher works on individual bytes. ARCFour supports keys from 8 bits up to 2048 bits.
You may be wondering what we mean with "ARCFour is fully compatible with the RC4TM cipher". Basically, it means that both algorithms produce the same output, given the same input. Hence, both algorithms are interchangable. ARCFour stands for "Alternative RC Four" or "Alleged RC Four".
One might argue that ARCFour and RC4 are two identical algorithms, however this cannot be verified since RSA Security Inc. has never released the source code of the RC4 algorithm.