encrypted email software

[J. Michael Diehl]

According to Mark Eichin:
> 
> 	The only "backdoor" concept I've heard which had a technical
> basis behind it was a few years back, when some researcher figured out
> a way to *produce* S-boxes with particular types of holes, and
> concluded that it was impossible to identify if the holes where there
> or not unless you knew the precise formulation... I think it even had
> a two-of-three challenge, ie, published 3 sets of s-boxes, one or two
> of which were "trapped" in this way, as a challenge for people to find
> methods of locating them. (The technical basis stops there -- the
> psychological or political question that follows is "did NSA/IBM know
> about this technique? Assuming they did, did they choose the s-boxes
> with or without holes?")

Could someone tell me what an s-box is?  Thanx in advance.
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| J. Michael Diehl ;-)  | I thought I was wrong once. | PGP KEY |
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