Re: [DNSOP] Terminology question: split DNS

Matthew Pounsett <matt@conundrum.com> Wed, 21 March 2018 18:15 UTC

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From: Matthew Pounsett <matt@conundrum.com>
Date: Wed, 21 Mar 2018 14:15:03 -0400
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To: Ted Lemon <mellon@fugue.com>
Cc: Matt Larson <matt@kahlerlarson.org>, dnsop <dnsop@ietf.org>, "Darcy Kevin (FCA)" <kevin.darcy@fcagroup.com>
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Subject: Re: [DNSOP] Terminology question: split DNS
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On 20 March 2018 at 11:10, Ted Lemon <mellon@fugue.com> wrote:

> On Mar 20, 2018, at 3:05 PM, Matt Larson <matt@kahlerlarson.org> wrote:
>
> +1 to "split DNS", which has always been the term I've used and heard. I
> completely agree that "split horizon" muddies the water by referring to a
> routing concept that probably pre-dates widespread use of split DNS.
>
>
> The term "split horizon" was common at one time, and I think we need to
> say what it means in this context.   I think it makes sense to point out
> that it is not the currently preferred term, and that people shouldn't use
> it anymore, but it's useful to clue people in as to what it means.
>
> +1.  I've heard split-horizon and views used more than just "split DNS" in
my career to refer to answering differently based on source address,
destination address (where the server has more than one), and/or
authentication (TSIG, SIG(0)).  It makes sense that split-horizon should be
noted as not being the preferred term, but it should be there since it does
get used to describe the same thing.

I think I've seen in other places in this thread an implication that we
should incorporate broader uses of providing alternate responses, and I
don't agree with that.  GSLB, geolocation, and other types of alternate
responses may be cousins to views, but they have their own definitions.