Re: ULA scope [draft-ietf-6man-rfc3484-revise-05.txt]

Mark Andrews <marka@isc.org> Mon, 19 March 2012 22:29 UTC

Return-Path: <marka@isc.org>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 6950F21E8012 for <ipv6@ietfa.amsl.com>; Mon, 19 Mar 2012 15:29:23 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.904
X-Spam-Level:
X-Spam-Status: No, score=-1.904 tagged_above=-999 required=5 tests=[AWL=-0.597, BAYES_00=-2.599, MISSING_HEADERS=1.292]
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 oIle4w57zlJk for <ipv6@ietfa.amsl.com>; Mon, 19 Mar 2012 15:29:23 -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 CE47321E800C for <ipv6@ietf.org>; Mon, 19 Mar 2012 15:29:22 -0700 (PDT)
Received: from bikeshed.isc.org (bikeshed.isc.org [IPv6:2001:4f8:3:d::19]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client CN "mail.isc.org", Issuer "RapidSSL CA" (not verified)) by mx.pao1.isc.org (Postfix) with ESMTPS id B2DF6C944A; Mon, 19 Mar 2012 22:29:11 +0000 (UTC) (envelope-from marka@isc.org)
Received: from drugs.dv.isc.org (unknown [IPv6:2001:470:1f00:820:645b:31fe:90c7:4d73]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by bikeshed.isc.org (Postfix) with ESMTPSA id 332FE216C36; Mon, 19 Mar 2012 22:29:11 +0000 (UTC) (envelope-from marka@isc.org)
Received: from drugs.dv.isc.org (localhost [127.0.0.1]) by drugs.dv.isc.org (Postfix) with ESMTP id 843801EAD52B; Tue, 20 Mar 2012 09:29:06 +1100 (EST)
From: Mark Andrews <marka@isc.org>
References: <4EB3F3D6.4090302@innovationslab.net><4EEA3D20.7020603@innovationslab.net><CAKFn1SFvs0PzBXtEWWo814Oe5TJmbQEJBm5FeYJY5xzrr=KFSw@mail.gmail.com><4EEA5793.8080800@gmail.com><CAKFn1SHA-=cQ_=5rJVLVMvQYXoTL_D1dCR=uWZK-qFrcGp6P-w@mail.gmail.com><4EEA7AF8.2090508@gmail.com><CAC1-dtn9M8-9cPAmkhCiGV0Gi5+Gfs8GAssTOaA-ZFhyUY3feg@mail.gmail.com><9B57C850BB53634CACEC56EF4853FF653B3C3777@TK5EX14MBXW601.wingroup.windeploy.ntdev.microsoft.com><9B57C850BB53634CACEC56EF4853FF653B3EDB9E@TK5EX14MBXW601.wingroup.windeploy.ntdev.microsoft.com><E6E7EE34-8244-40B6-84C1-C79E8BDE7921@nttv6.net><4F3ABFBA.8060605@gmail.com><29EBA88D-BDB1-464C-915F-B9063578DC51@nttv6.net><9B57C850BB53634CACEC56EF4853FF653B45BB08@TK5EX14MBXW604.wingroup.windeploy.ntdev.microsoft.com><C8827D58-5C69-4A44-B9CE-86791466814E@nttv6.net><4F63896E.10607@gmail.com> <CAFtBC=8=__8GdtExB8oYgA7pOfjxNfXCLzuOXz7_UKCPhwjenw@mail.gmail.com> <5B6B2B64C9FE2A489045EEEADDAFF2C3043A22C2@XMB-RCD-109.cisco.com> <4F64026B.8080308@gmail .com> <9B57C850BB5 3634 CACEC56EF4853FF653B4A639F@TK5EX14MBXW603.wingroup.windeploy.ntdev.microsoft.com> <00f801cd05a2$abfce190$03f6a4b0$@lampo@eurid.eu> <20120319141402.DAECF1EAC06D@drugs.dv.isc.org> <01f401cd05dc$20914df0$61b3e9d0$@lampo@eurid.eu> <20120319220801.964E91EAD466@drugs.dv.isc.org>
Subject: Re: ULA scope [draft-ietf-6man-rfc3484-revise-05.txt]
In-reply-to: Your message of "Tue, 20 Mar 2012 09:08:01 +1100." <20120319220801.964E91EAD466@drugs.dv.isc.org>
Date: Tue, 20 Mar 2012 09:29:06 +1100
Message-Id: <20120319222906.843801EAD52B@drugs.dv.isc.org>
Cc: 'Brian Haberman' <brian@innovationslab.net>, ipv6@ietf.org, 'Arifumi Matsumoto' <a@arifumi.net>, 'Bob Hinden' <bob.hinden@gmail.com>, 'Dave Thaler' <dthaler@microsoft.com>, Marc Lampo <marc.lampo@eurid.eu>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ipv6>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 19 Mar 2012 22:29:23 -0000

In message <20120319220801.964E91EAD466@drugs.dv.isc.org>, Mark Andrews writes:
> 
> In message <01f401cd05dc$20914df0$61b3e9d0$@lampo@eurid.eu>, "Marc Lampo" wri
> te
> s:
> > Allow me to clarify with an example.
> > 
> > In my IP(v4) experience, I have a customer with offices over multiple
> > Continents - private address space in use everywhere -
> > site-to-site VPN's (== connecting networks) connect the offices.
> > 
> > If I map to IPv6 this might be one /48 ULA range;
> > Some networks in central HQ, others remotely, behind site-to-site VPN.
> > 
> > --> if one end-node in one network wants to reach another,
> >      in another network, its traffic must travel through the VPN.
> > 
> > Please observe that using public addresses (not using ULA)
> > might do away with address selection "challenges"
> > but would imply that networks on all continents will have to be
> > renumbered if the central HQ changes ISP (and hence : public IPv6
> > addresses).
> > Something I'd like to avoid ...
> > 
> > Kind regards,
> > 
> > Marc Lampo
> 
> Well with a single ULA you have 65536 /64 sized networks to use
> where ever you want.  You have ULA:0000/56 in Paris, ULA:0100/55
> in New York.  You don't have to keep things bit aligned but it
> helps.  65536 prefixes isn't a lot of routing information.  Think
> of it in IPv4 terms as 10/8 and you are handing out /24 for each
> subnet except you know you won't need more than /24 ever.

Alternatively you can give each site its own ULA and you use non
default address selection rules.  Remember we are talking about the
default rules here.  There are billions of more homes than there
are businesses.

They would use rules like the follow which give all the sites a
common label:

	::1      50   0
	ULA1:/48 45 100
	ULA2:/48 45 100
	ULA3:/48 45 100
	::/0     40   1
	2002::	 30   2
	fc00::	 0    3
 
Whereas the default rules generate a table like if it was multi-homed
to three sites:

	::1      50   0
	ULA1:/48 45   4
	ULA2:/48 45   5
	ULA3:/48 45   6
	::/0     40   1
	2002::	 30   2
	fc00::	 0    3
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka@isc.org