Re: State machine hypothesis...

[Rene Zandbergen <r_zandbergen@xxxxxxxxx>]

Dear all,

 Nick Pelling <incoming@xxxxxxxxxxxxxxxxx> wrote:

> My theory du jour would look something like:-

I cannot of course disprove it, but here are some
thoughts that challenge your 'theory du jour':

> (1) polyalphabetic, but with a non-obvious state
> switching mechanism.

The low entropy is a pointer against poly-alphabetic
substitution. Such a cipher would increase it. Also,
IIRC, the VMs is a bit too early for that.

> (2) (space) is a character, not a space

All statistics I've seen point into the direction
that spaces (at least most if not all) are true
word spaces.

> (3) ends of lines padded with steganographic nulls
> (perhaps EVA m is involved)

Note that many labels (which are relatively short 
words) end also with these characters. Eva-m is rather
frequent, see e.g. the Pisces labels. Some labels
differ from each other only by the end character.

> (4) symbols are sorted by ranking within states for
> a low entropy output stream
> 
> It's the non-obvious state switching mechanism that
> makes it non-crackable 

Mike Roe once wrote something along the lines that
for every known plaintext ever written (at least
as long as it is not much longer than the VMs), there
exists a cipher or mechanism that translates this
text into the VMs. It is the art of finding the 
plaintext which has an acceptable cipher / mechanism.

If you are going to look for a non-obvious 
state-switching mechanism you risk falling into the
same pit as Strong / Rayman / Glen Claston.
But then again, you may be right and I may be wrong
end I don't want to leave the impression that I
think I should tell you what to do :-). 

Cheers, Rene 

__________________________________________________
Do You Yahoo!?
Make international calls for as low as $.04/minute with Yahoo! Messenger
http://phonecard.yahoo.com/