Re: [v6ops] Implementation Status of PREF64

Gert Doering <gert@space.net> Wed, 13 October 2021 17:37 UTC

Return-Path: <gert@space.net>
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 7D1D63A086A for <v6ops@ietfa.amsl.com>; Wed, 13 Oct 2021 10:37:58 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.099
X-Spam-Level:
X-Spam-Status: No, score=-2.099 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=space.net
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 m3j6AsztIRi6 for <v6ops@ietfa.amsl.com>; Wed, 13 Oct 2021 10:37:53 -0700 (PDT)
Received: from gatekeeper1-relay.space.net (gatekeeper1-relay.space.net [IPv6:2001:608:3:85::38]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id DC2043A08A7 for <v6ops@ietf.org>; Wed, 13 Oct 2021 10:37:49 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=space.net; i=@space.net; q=dns/txt; s=esa; t=1634146670; x=1665682670; h=date:from:to:subject:message-id:references:mime-version: in-reply-to; bh=AUS43D5+5xXdDIlH2mBpX56pBwx74nbRdqSu9S69mKQ=; b=AdXDYwOQdLx6iy1J3k2WBthFk8ajDp49BU6r1rznbyb8bNeOFIh0jGFd pYRCGZ0BN7zW4j8JVKn+1IQwgKIvGS1+m0w5an5YnT7/ByGiHbmk1Aok+ z+f8Nla8ZPomNKDxiSmzSO8a1HBhm7ogNGEYxsty+c0c3x3DDNb7yxRQ0 57c3EsRU+TMWrnzcLv8bilCF1ojRkmZCYWFTmTAh+HZDCzWDWx+CWBrOY KVIo2RacB4clZpRH23L0ev4+BiakuEsHLseqaG8qaTI8m487ek3+kiwW6 BXFB8Fu4ATVXwkm6uATfpGJgUli27JTPe72r7m07YVgrWA1bLHJbFgAAs g==;
X-SpaceNet-SBRS: None
Received: from mobil.space.net ([195.30.115.67]) by gatekeeper1-relay.space.net with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2021 19:37:47 +0200
X-Original-To: v6ops@ietf.org
Received: from mobil.space.net (localhost [IPv6:::1]) by mobil.space.net (Postfix) with ESMTP id 060D741930 for <v6ops@ietf.org>; Wed, 13 Oct 2021 19:37:47 +0200 (CEST)
X-SpaceNet-Relay: true
X-SpaceNet-Relay: true
X-SpaceNet-Relay: true
Received: from moebius4.space.net (moebius4.space.net [IPv6:2001:608:2:2::251]) by mobil.space.net (Postfix) with ESMTP id A294141202; Wed, 13 Oct 2021 19:37:46 +0200 (CEST)
Received: by moebius4.space.net (Postfix, from userid 1007) id 9CB95126EA7; Wed, 13 Oct 2021 19:37:46 +0200 (CEST)
Date: Wed, 13 Oct 2021 19:37:46 +0200
From: Gert Doering <gert@space.net>
To: Gert Doering <gert@space.net>, Philip Homburg <pch-v6ops-10@u-1.phicoh.com>, v6ops@ietf.org
Message-ID: <YWcZaur+BLe5iNCx@Space.Net>
References: <CAPt1N1ma45GKqXcvjHUGCYFKVbEGp3OuT013pZhrnOkFFLMiQA@mail.gmail.com> <CAKD1Yr2Pe+=tNkA7Ou9KeMkgFhcdSb8WxgVn1w9MauusMEhRcw@mail.gmail.com> <CO1PR11MB4881076DFF8A145C8CD818B8D8B69@CO1PR11MB4881.namprd11.prod.outlook.com> <A188D974-3CEB-497F-93EA-B66C77D2CA90@delong.com> <YWW1ghmjueHmfCEb@Space.Net> <m1maKp6-0000I3C@stereo.hq.phicoh.net> <YWW8FPkRuxCBFp3o@Space.Net> <D0510DEB-04FF-4864-9363-6FC40C686C22@delong.com> <YWcQKwK3lAKpl7y1@Space.Net> <DFD526B0-7CA3-4445-910F-425142C0AEDA@delong.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="BYU0Blcyn5QJ6S9A"
Content-Disposition: inline
In-Reply-To: <DFD526B0-7CA3-4445-910F-425142C0AEDA@delong.com>
Archived-At: <https://mailarchive.ietf.org/arch/msg/v6ops/NivGDPIcJzWCDwx3G7CjDNLLIGI>
Subject: Re: [v6ops] Implementation Status of PREF64
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.29
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: <https://mailarchive.ietf.org/arch/browse/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: Wed, 13 Oct 2021 17:37:58 -0000

Hi,

On Wed, Oct 13, 2021 at 10:25:36AM -0700, Owen DeLong wrote:
> > So far I have not seen any data that supports "/64 was a good idea" :-)
> 
> It???s working quite well in a number of networks I???ve deployed.
> 
> It???s convenient for EUI-64 addressing.
> 
> Reviewing the record, it seems we were destined for something like 64-bit
> addressing overall before IETF decided to consider EUI-64 addressing and
> added 64-bits to the plan, so one can argue that without the idea of
> universal /64 addressing we???d have a whole lot fewer network numbers
> available.
> 
> So now you have seen data to suggest that /64 was a good idea.
> 
> Do you have any data support your claim that /64 was not?

What part of "yeah, it works for me" makes it a *good* idea?

So did /80s, when they were the latest fashion.

What part of "EUI-64" is a *good* idea, now that everyone is actually
moving away from EUI-64, because it has more undesirable properties than
"oh, yeah, it was there and is convenient"?

Nah.  8+8 was a brilliant idea that did not happen - and nothing else
in a /64 is more than "we can't find consensus to change that".


On the downside:

 - it creates pressure on the number of subnets in reasonably structured
   deployments (think of the number of subnets you can have with a /96
   standard subnet size...)

 - ND exhaustion attacks (which arguably would happen in a /96 just as well)


Gert Doering
        -- NetMaster
-- 
have you enabled IPv6 on something today...?

SpaceNet AG                      Vorstand: Sebastian v. Bomhard, Michael Emmer
Joseph-Dollinger-Bogen 14        Aufsichtsratsvors.: A. Grundner-Culemann
D-80807 Muenchen                 HRB: 136055 (AG Muenchen)
Tel: +49 (0)89/32356-444         USt-IdNr.: DE813185279