Re: [DNSOP] [internet-drafts@ietf.org: I-D Action: draft-bortzmeyer-dnsop-nxdomain-cut-00.txt]

Tony Finch <dot@dotat.at> Wed, 18 November 2015 15:31 UTC

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Date: Wed, 18 Nov 2015 15:31:13 +0000
From: Tony Finch <dot@dotat.at>
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Subject: Re: [DNSOP] [internet-drafts@ietf.org: I-D Action: draft-bortzmeyer-dnsop-nxdomain-cut-00.txt]
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Wessels, Duane <dwessels@verisign.com> wrote:
>
> For a name like foo.bar.example.com and an NXDOMAIN response from example.com
> we can't assume that there would be a zone cut between foo and bar.

If QNAME = foo.bar.example.com and NXDOMAIN SOA owner = example.com, you
know that foo.bar.example.com and bar.example.com are not delegation
points. You know that foo.bar.example.com does not exist. You do not know
whether bar.example.com exists. (You can find that out with another query
if you want to raise the NXDOMAIN bar.)

Tony.
-- 
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