Serpent is a 128-bit 32-round block cipher with variable key lengths, including 128, 192 and 256 bit keys conjectured to be at least as secure as three-key triple-DES. <p> Serpent was designed by Ross Anderson, Eli Biham and Lars Knudsen as a candidate algorithm for the NIST AES Quest.> <p> For full details see the <a href="http://www.cl.cam.ac.uk/~rja14/serpent.html">The Serpent home page</a>