Re: [DNSOP] Clarifying referrals (#35)

Tony Finch <dot@dotat.at> Wed, 29 November 2017 12:32 UTC

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Date: Wed, 29 Nov 2017 12:32:32 +0000
From: Tony Finch <dot@dotat.at>
To: Andrew Sullivan <ajs@anvilwalrusden.com>
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Subject: Re: [DNSOP] Clarifying referrals (#35)
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Andrew Sullivan <ajs@anvilwalrusden.com> wrote:
>
> I'm not totally convinced, but I can certainly see the argument.  If
> we added to the text I proposed something like, "Many people use the
> unqualified term 'referral' to mean only a downward referral," would
> that help?

Well, I would say, s/many people/Paul Mockapetris/  :-)

> > answer the query. I have also seen the term "implicit referral" meaning
> > the authority section from a recursive response, since the idea was that a
> > downstream cache might use those records to answer future queries more
> > efficiently (though doing that is no longer considered safe).
>
> Hmm.  It seems like we ought to add that point about implicit
> referral.

Oh, actually, (now I re-read my old definition properly) that term is used
in RFC 2308 section 6.

> I wonder how this is related to the "partial referral" Mark
> is talking about (see elsewhere in this thread).

They look similar but have different AA bits, if I understand correctly.
An implicit referral comes from the cache whereas Mark's CNAME plus
referral comes from authoritative data.

Tony.
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