Re: [DNSOP] I-D Action: draft-ietf-dnsop-refuse-any-04.txt

Tony Finch <dot@dotat.at> Mon, 13 February 2017 13:03 UTC

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Date: Mon, 13 Feb 2017 13:03:18 +0000
From: Tony Finch <dot@dotat.at>
To: Richard Gibson <rgibson@dyn.com>
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Cc: Ólafur Guðmundsson <olafur@cloudflare.com>, dnsop <dnsop@ietf.org>
Subject: Re: [DNSOP] I-D Action: draft-ietf-dnsop-refuse-any-04.txt
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Richard Gibson <rgibson@dyn.com> wrote:

> Because without such a signal, humans using ANY for legitimate diagnostic
> purposes have no means of differentiating section 4.1/4.3 "subset"
> responses from conventional responses where there just happen to be only a
> small number of RRSets at the queried name, encouraging (or at least doing
> nothing to dissuade) a conclusion that the response is in fact conventional
> and complete.

There are several ways to avoid this pitfall:

Use TCP

Look for an NSEC(3) record

Query for the specific types you want to know about

Tony.
-- 
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