On Sun, 21 Apr 2002 15:48:57 +0200, kingruedi said: > That is good! so I can use MD5 sums as key No you can't. An MD5 digest is just 16 bytes. The usual way to create a key is by using a ranodm key and having some key agreement mechanism. AES256 doesn't buy you anything when using a weak keay (i.e. which can be easy attacked with an dictionary attack).