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24 June 1998

Subject: Re: Skipjack KEA Up 
Date: Wed, 24 Jun 1998 21:55:29 +0000
From: Markus Kuhn <>

John Young wrote on 1998-06-24 16:01 UTC:
> Others have asked when the code will be released, if ever. 
> One surmise is that will be done only to encryption vendors 
> who will be hogtied in the usual fashion.

Implementing and testing SKIPJACK from the NIST spec was a simple
straightforward ~2 hour programming exercise. Example code is available

SKIPJACK is not that particularly interesting, except that it looks like
it was designed by people who are also responsible for designing
brute-force keysearch farms. I found the so far three published papers
from AES contributor groups much more exciting.


Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at,  home page: <>