Re: [DNSOP] Terminology question: split DNS

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

Return-Path: <matt@conundrum.com>
X-Original-To: dnsop@ietfa.amsl.com
Delivered-To: dnsop@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 0420512762F for <dnsop@ietfa.amsl.com>; Wed, 21 Mar 2018 11:15:07 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.598
X-Spam-Level:
X-Spam-Status: No, score=-2.598 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=conundrum-com.20150623.gappssmtp.com
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QCjxuEojpVU3 for <dnsop@ietfa.amsl.com>; Wed, 21 Mar 2018 11:15:05 -0700 (PDT)
Received: from mail-it0-x231.google.com (mail-it0-x231.google.com [IPv6:2607:f8b0:4001:c0b::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 2AA28127863 for <dnsop@ietf.org>; Wed, 21 Mar 2018 11:15:05 -0700 (PDT)
Received: by mail-it0-x231.google.com with SMTP id w3-v6so8042998itc.4 for <dnsop@ietf.org>; Wed, 21 Mar 2018 11:15:05 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=conundrum-com.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=B7OJtcmgDI0NfuKnAlMswwYyy06foWbwqE3vZNgRy54=; b=cN6redGR/ZSWG+IRs5gHg1GLavJrGQtIH9pM0ngZzMxi2xtqf7LoEoTVMS9vKK2lnN DPJ3iPxZOsb1mwVU8eQSnN1k7rPT9Jyidn7MvkfSjfDfTbhhsxViNuW20+vGBt4SVgyg SlLPEte63S4P2GkTWI9Q/GWWUWz1MlGTtex1jPLKp1QkuBVjQKFCE5XloTgRfOA1VRun Ttk8dO9nVjX8DNTB/nvLA/qrpOA5BwdsRaaSs7MuCqhFDR49F+bz0SScIsGGOkx0z7dz /GIEJsNrN6paah7XC3YTlkimqWKZl49+xFL/WQnGZTc70o8vYOQ85XsjDgXJ+ktJgu+K SiSw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=B7OJtcmgDI0NfuKnAlMswwYyy06foWbwqE3vZNgRy54=; b=Jd5mrZQypdMhJmEHUPuw2Ne7atqlpT0NHxZsT9GnJBqtbbPpXwrD+2rL+uSmweOxg9 98ZtSKNQZ3bDmK++K+0wRyvAiahmsHmI40BKT0dZBJi+HYfT6rUgWfZEZ8O18BOP0DAf xd9r9W0Yla9phj56AsWhr7gGqF3XcWZnG09RAI0aJ6eS5ZhocRpWnyjA5+bthLymw2iz NUcAe3O3Uz3FyyRrVbKBrcl3szUdD6RWVQBq0Cazd7EKWcoT4k2tzMMYlNBjYRbfoZmx wFEI8UnTV0S+g4N2s/Fum8QDQf56zlyZzNhRmK8kG+2mReO1MxjCzntt9whphYEGatcB wAWg==
X-Gm-Message-State: AElRT7Fm4SIcsEdsUZMXuMl7YseN7cQsQHoPKsGlbgjgDn+fAagwDCHm V6jhqsK67CgpLAFe3JFGYggAV7IRpJ+av8O4U7Lxfg==
X-Google-Smtp-Source: AG47ELu1AJLSwL93SIE7ZIPduIBOpnA2tdE7pyucGD6dkRGRKjiyAfgHMGpsDAJHL3UIAlEs7VCpx2hbp62hXXXLiAw=
X-Received: by 2002:a24:d181:: with SMTP id w123-v6mr5629362itg.38.1521656104396; Wed, 21 Mar 2018 11:15:04 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.2.112.197 with HTTP; Wed, 21 Mar 2018 11:15:03 -0700 (PDT)
In-Reply-To: <D3C66C0F-8016-4226-BE6C-7EDF748AD63F@fugue.com>
References: <3D490CA8-0733-47AD-A088-113B1116B207@vpnc.org> <5AAFF968.10407@redbarn.org> <6632a381f8234a96ad6235a519850da3@mxph4chrw.fgremc.it> <379CB7DE-A56C-4415-A9AC-C0F7AAB2A05D@kahlerlarson.org> <D3C66C0F-8016-4226-BE6C-7EDF748AD63F@fugue.com>
From: Matthew Pounsett <matt@conundrum.com>
Date: Wed, 21 Mar 2018 14:15:03 -0400
Message-ID: <CAAiTEH-G3ywHWkHe7PmSfo43JqnVzvtBmfDeuod2_zK7dPHguw@mail.gmail.com>
To: Ted Lemon <mellon@fugue.com>
Cc: Matt Larson <matt@kahlerlarson.org>, dnsop <dnsop@ietf.org>, "Darcy Kevin (FCA)" <kevin.darcy@fcagroup.com>
Content-Type: multipart/alternative; boundary="00000000000092c4160567f02b16"
Archived-At: <https://mailarchive.ietf.org/arch/msg/dnsop/74CPr7-v5LZ_liU3FCSWXITvws8>
Subject: Re: [DNSOP] Terminology question: split DNS
X-BeenThere: dnsop@ietf.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: IETF DNSOP WG mailing list <dnsop.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dnsop>, <mailto:dnsop-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dnsop/>
List-Post: <mailto:dnsop@ietf.org>
List-Help: <mailto:dnsop-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dnsop>, <mailto:dnsop-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 21 Mar 2018 18:15:07 -0000

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.