Re: [DNSOP] draft-ietf-dnsop-rfc7816bis: hopefully ready for WG Last Call

Tony Finch <dot@dotat.at> Fri, 06 November 2020 00:43 UTC

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Date: Fri, 6 Nov 2020 00:43:33 +0000
From: Tony Finch <dot@dotat.at>
To: Dave Lawrence <tale@dd.org>
cc: dnsop <dnsop@ietf.org>
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Subject: Re: [DNSOP] draft-ietf-dnsop-rfc7816bis: hopefully ready for WG Last Call
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Dave Lawrence <tale@dd.org> wrote:
>
> Could you please clarify explicitly what should happen in the case of
> encountering CNAMEs?  Or DNAMEs?

I guess when I originally sketched a qname minimization algorithm
https://mailarchive.ietf.org/arch/msg/dns-privacy/gAgGx9Zz6W0OfyRdJ0Rx7xxmHDg/
I intended that it would slot into the RFC 1034 resolver algorithm
https://tools.ietf.org/html/rfc1034#section-4.3.2
which treats QNAME as a variable name rather than a protocol field, so
the QNAME changes when the resolver chases a CNAME.

That was probably a bad idea: on balance I think it's better to make a
clear distinction between protocol fields and variables in algorithms.
Elsewhere RFC 1034 uses SNAME for the variable containing the name we are
searching for https://tools.ietf.org/html/rfc1034#section-5.3.3
which would be better if it hadn't used QNAME for the same thing elsewhere
:-)

Tony.
-- 
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