Re: [v6ops] draft-moreiras-v6ops-rfc3849bis-00

Mark Andrews <marka@isc.org> Tue, 13 August 2013 07:02 UTC

Return-Path: <marka@isc.org>
X-Original-To: v6ops@ietfa.amsl.com
Delivered-To: v6ops@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D014A11E8142 for <v6ops@ietfa.amsl.com>; Tue, 13 Aug 2013 00:02:20 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.819
X-Spam-Level:
X-Spam-Status: No, score=-1.819 tagged_above=-999 required=5 tests=[AWL=0.780, BAYES_00=-2.599]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dL+mdoda1w57 for <v6ops@ietfa.amsl.com>; Tue, 13 Aug 2013 00:02:16 -0700 (PDT)
Received: from mx.pao1.isc.org (mx.pao1.isc.org [IPv6:2001:4f8:0:2::2b]) by ietfa.amsl.com (Postfix) with ESMTP id EF02811E8118 for <v6ops@ietf.org>; Tue, 13 Aug 2013 00:02:15 -0700 (PDT)
Received: from mx.pao1.isc.org (localhost [127.0.0.1]) by mx.pao1.isc.org (Postfix) with ESMTP id 92BB8C9425; Tue, 13 Aug 2013 07:02:01 +0000 (UTC) (envelope-from marka@isc.org)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isc.org; s=dkim2012; t=1376377333; bh=Gn+pDHeDlOb/RPdDmbAdlvcg0Tdsxi1ZKyQsTXNIuu8=; h=To:Cc:From:References:Subject:In-reply-to:Date; b=SbMcdhX0L47ft1AQYGo4kHgvnwEw046iNScdvF6YMpyFNd56p/Kyczoj06o+vMyCc 9daaRYrb3pwtNUM3HLIwLRMgi+IMAvZ3nmeF5lPWViqOVIkN/gJypU6f7Zmdz2xkaW 4kdsej08fQN/JgXZk9vGI3lF6dKIO07cUSySRaxg=
Received: from zmx1.isc.org (zmx1.isc.org [149.20.0.20]) by mx.pao1.isc.org (Postfix) with ESMTP; Tue, 13 Aug 2013 07:02:01 +0000 (UTC) (envelope-from marka@isc.org)
Received: from localhost (localhost [127.0.0.1]) by zmx1.isc.org (Postfix) with ESMTP id 934AB160438; Tue, 13 Aug 2013 07:06:42 +0000 (UTC)
Received: from zmx1.isc.org ([127.0.0.1]) by localhost (zmx1.isc.org [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id zWM5MjfeGxHu; Tue, 13 Aug 2013 07:06:42 +0000 (UTC)
Received: from zmx1.isc.org (localhost [127.0.0.1]) by zmx1.isc.org (Postfix) with ESMTP id ECC961601E7; Tue, 13 Aug 2013 07:06:41 +0000 (UTC)
Received: from drugs.dv.isc.org (c211-30-183-50.carlnfd1.nsw.optusnet.com.au [211.30.183.50]) by zmx1.isc.org (Postfix) with ESMTPSA id B9EFA1601C2; Tue, 13 Aug 2013 07:06:41 +0000 (UTC)
Received: from drugs.dv.isc.org (localhost [IPv6:::1]) by drugs.dv.isc.org (Postfix) with ESMTP id 6D9D5384B2C5; Tue, 13 Aug 2013 17:01:57 +1000 (EST)
To: Owen DeLong <owen@delong.com>
From: Mark Andrews <marka@isc.org>
References: <5207D42F.2030302@nic.br> <5207E319.6070601@nic.br> <B66D2D0C-DE6D-49CC-A87A-7C65B5360DB4@delong.com> <20130811233819.AE71C383CF0C@drugs.dv.isc.org> <5773BB43-B910-482A-A6EF-AFCD2B6AE181@delong.com> <20130812211453.89A833845161@drugs.dv.isc.org> <0B5D3829-C490-4A7A-B185-9D072ACCF4F5@delong.com> <20130813025336.918353846F7A@drugs.dv.isc.org> <696F80F4-97A7-4A52-B9F0-8A3CFA4B0B30@delong.com>
In-reply-to: Your message of "Mon, 12 Aug 2013 21:52:32 -0700." <696F80F4-97A7-4A52-B9F0-8A3CFA4B0B30@delong.com>
Date: Tue, 13 Aug 2013 17:01:57 +1000
Message-Id: <20130813070157.6D9D5384B2C5@drugs.dv.isc.org>
X-DCC--Metrics: post.isc.org; whitelist
Cc: Alejandro Acosta <aacosta@rocketmail.com>, v6ops@ietf.org
Subject: Re: [v6ops] draft-moreiras-v6ops-rfc3849bis-00
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: v6ops discussion list <v6ops.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/v6ops>, <mailto:v6ops-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/v6ops>
List-Post: <mailto:v6ops@ietf.org>
List-Help: <mailto:v6ops-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/v6ops>, <mailto:v6ops-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 13 Aug 2013 07:02:21 -0000

In message <696F80F4-97A7-4A52-B9F0-8A3CFA4B0B30@delong.com>om>, Owen DeLong writes:
>
> On Aug 12, 2013, at 7:53 PM, Mark Andrews <marka@isc.org> wrote:
>
> >
> > In message <0B5D3829-C490-4A7A-B185-9D072ACCF4F5@delong.com>om>, Owen
> DeLong writes:
> >> Given the wide prevalence of RFC-1918 islands that were merged with
> >> double NATs instead of repaired in the IPv4 world (which I believe =
> >> likely
> >> outnumber the number of environments where one or the other entity
> >> was actually renumbered into non-conflicting space), I think we have
> >> strong evidence that this is not true.
> >
> > And how many RFC-1918 islands had alternate address space to renumber
> > into?
>
> The vast majority of the ones I am aware of. Very few companies are using
> all of the RFC-1918 space entirely.
>
> > How many RFC-1918 islands started out knowing they would have to
> > renumber if there was a collision when they connected to someone
> > else?
>
> Virtually all of them.
>
> > How many RFC-1918 islands were designed to run with multiple addresses
> > per interface from day one?
>
> A few, but not many.
>
> > How many RFC-1918 islands run dual IPv4 addressed?
>
> A few, but not many.
>
> > Now ask the same questions of ULA islands.  You have different
> > solutions available with ULA than you do with RFC-1918.  NAT is not
> > required to fix ULA collisions.  ULA sites with collisions don't
> > even need to renumber out of the colliding prefixes if they don't
> > want to.
>
> 1. Same answer.
> 2. Same answer.
> 3. Admittedly, this is reversed, but I don't think that will make a
> significant difference.
> 4. Admittedly, this is reversed, but I consider it pretty much identical
> to question 3.
>
> NAT is not required to fix RFC-1918 collisions IN MOST CASES. It's simply
> a lot
> more convenient (for the people making the decision) at the cost of great
> woes
> for the people using the networks.
>
> So far, you've offered NOTHING to suggest that this would be different
> with ULA.
>
> Owen

With ULA you end up with:

	site1: P1, P2 announce P2 to site2
	site2: P1, P3 announce P3 to site1

When you have two sites colliding on P1.  (P1, P2 and P3 are different
ULA prefixes).

You have IP stacks that are designed to deal with multiple prefixes
and to choose particular source addresses for particular destination
addresses.

You have applications that are designed to deal with multiple
addresses.

IPv4 only stacks don't have all of these features which forces one
to use NAT.

With IPv6 they are there so you can depend on them and take advantage
of them.  If P2 and P3 differ only in the 48th bit longest match
will select the right source address.

Mark
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka@isc.org