Dale Thorn wrote:
Mullen Patrick wrote:
To take this one step further, has anyone tried to ever use this method as an encryption method? You could hide data in a stream of random bits, using position as the encryption method.
It doesn't matter *what* you do with your bits. The key thing to remember when analyzing your encryption method is that the foundation of your security rests on the difficulty of reversing the numeric sequence that drives the encryption. If I know you're using this RNG-driven steganographic message mixer, then if I can break your RNG I'm done. If I know you're scrambling bits in a file according to an RNG, if I break your RNG I'm done. The key is therefore to make the RNG cryptographically secure. Once you've done that, then there's questionable value in doing anything fancier than straight CBC (or something like that) to encrypt your plaintext. Note that simple functional composition of one or more simple insecure RNG's does not necessarily give you a stronger RNG (in fact it usually doesn't). Cheap RNG's like what you get from the old UNIX "rand()" are simple little linear functions, which when composed give you more simple functions. ______c_________________________________________________________________ Mike M Nally * IBM % Tivoli * Austin TX * How quickly we forget that mailto:m5@tivoli.com mailto:m101@io.com * "deer processing" and "data http://www.io.com/~m101/ * processing" are different!