Subject: RE: Proposal to fix NSEC

From: "Hallam-Baker, Phillip" <[email-masked]>
Date: Thu, 20 May 2004 16:57:54 -0700

Interesting.

I am trying to work out the reason for the hash iterations.

Let us call the set of names in the zone 
	D = {d0, d1, d2, d3 ... dn}

The problem is to be able to enumerate the inverse of the set
	D' = { ]d0-d1[, ]d1-d2[ ... ]dn-d0[ }

It suffices to present one member of D' to prove that any given domain is
not a member of D.

To describe a member of D we simply specify dx, dx+1

So what you are saying is that we do not need to deal with D, we can apply a
one way function...

	HD = {H(d0), H(d1), ... H(dn) }

	HD' = { { ]H(d0)-H(d1)[, ]H(d1)-H(d2)[ ... ]H(dn)-H(d0)[ }

So why do we need to specify more than H(dx), (H(dx+1)) ???

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From: Ben Laurie <[email-masked]>
Date: Fri, 21 May 2004 06:02:56 +0100

> So why do we need to specify more than H(dx), (H(dx+1)) ???

To increase the cost of dictionary attacks.

Cheers,

Ben.

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