RC5 is a fast and simple #Block Cipher, invented by Ron Rivest, utilises data-dependent rotations that could have a variable number of rounds of #round funnction (up to 255 rounds) and variable-length key (up to 2048 bits). It can be used to encrypt a 64-bit large data block. It is suited for both software and hardware encryption. Moreover, it can adapt to processors of different word lengths with low memory requirement and provide high security guarantee.