Re: [v6ops] new draft: draft-colitti-v6ops-host-addr-availability
Tore Anderson <tore@fud.no> Tue, 07 July 2015 09:08 UTC
Return-Path: <tore@fud.no>
X-Original-To: v6ops@ietfa.amsl.com
Delivered-To: v6ops@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A1C551A7D85 for <v6ops@ietfa.amsl.com>; Tue, 7 Jul 2015 02:08:54 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -0.011
X-Spam-Level:
X-Spam-Status: No, score=-0.011 tagged_above=-999 required=5 tests=[BAYES_40=-0.001, T_RP_MATCHES_RCVD=-0.01] autolearn=ham
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 pS85euoFMbtG for <v6ops@ietfa.amsl.com>; Tue, 7 Jul 2015 02:08:52 -0700 (PDT)
Received: from greed.fud.no (greed.fud.no [IPv6:2a02:c0:1001:100::145]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id D36691A7D82 for <v6ops@ietf.org>; Tue, 7 Jul 2015 02:08:51 -0700 (PDT)
Received: from [2a02:c0:2:4:6666:17:0:1001] (port=53689 helo=echo.ms.redpill-linpro.com) by greed.fud.no with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from <tore@fud.no>) id 1ZCOrv-0006DS-Ex; Tue, 07 Jul 2015 11:08:47 +0200
Date: Tue, 07 Jul 2015 11:08:47 +0200
From: Tore Anderson <tore@fud.no>
To: v6ops@ietf.org
Message-ID: <20150707110847.5119162d@echo.ms.redpill-linpro.com>
In-Reply-To: <201507061147.t66Bl1AE028312@irp-lnx1.cisco.com>
References: <201507061147.t66Bl1AE028312@irp-lnx1.cisco.com>
X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.28; x86_64-redhat-linux-gnu)
MIME-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Archived-At: <http://mailarchive.ietf.org/arch/msg/v6ops/wtFcNHZ7vg1JVexjGbk6I6BYhow>
Cc: draft-colitti-v6ops-host-addr-availability@tools.ietf.org
Subject: Re: [v6ops] new draft: draft-colitti-v6ops-host-addr-availability
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.15
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: Tue, 07 Jul 2015 09:08:54 -0000
* fred@cisco.com > A new draft has been posted, at > http://tools.ietf.org/html/draft-colitti-v6ops-host-addr-availability. > Please take a look at it and comment. I read this draft. I strongly agree with its recommendation, and would support WG adoption. I have some feedback and suggestions, see below: 1) The abstract and section 6: What exactly is meant by "multiple"? Would a network conform to the recommendation by allowing 2 global addresses per host (given the current wording, I think so)? Or should it be 20? 200? I'd like to see a specific number, or at least a ballpark number, or failing that some text that explains why no attempt is being made to quantify what is OK and what is not. (I know this is a tough one. Sorry..) 2) Section 1.1: Includes the RFC 2119 key words but doesn't appear to make use o f them anywhere. Maybe s/recommended/RECOMMENDED/ in section 6? 3) Section 2 makes a reference to RFC 6433 section 5.9.4. I think there must be a typo on the RFC number; RFC6433 doesn't contain a section 5.9.4. 4) In Section 2: «DHCPv6 [RFC7217]». s/7217/3315/, surely? 5) In Section 2: «IPv6 hosts have the ability to configure additional IPv6 addresses from the on-link prefix without explicit requests to the network» isn't 100% correct, the hosts need to perform DAD first. Furthermore, that mechanism could be (ab)used by the network to block the host from obtaining additional addresses. 6) Nit: In section 3, some of the bullet points terminate with a full stop, some do not. Looks inconsistent. 7) Section 4: Just like to note that an address-unrestricted network will still be subject to the first three problems listed thanks to DAD. (Except DHCPv6-PD.) 8) Section 5: «the problems listed in section without disabling» is missing a reference to (I assume) section 4. 9) Section 7: «If the prefix is a /64, it can also reshare that prefix with any downstream clients via [RFC7278] /64 sharing». I think the reference to RFC7278 is improper. First, RFC7278 is 3GPP specific while DHCPv6-PD is not. Second, it discusses how to take a /64 that is a link prefix on an upstream interface and re-use it on a downstream interface. If you receive a delegated prefix (regardless of what its length is), that prefix is *not* a link prefix on your upstream interface and can simply be used on your downstream (or loopback) interfaces without restrictions. I suggest rewriting something like this: «The delegated prefix can also be reshared with any downstream clients, cf. [RFC3633] section 5.» 10) Table 1: Mentions that SLAAC provides "unlimited" addressing. I think that's a bit of a stretch, given hardware limitations. You can buy devices today that can only handle a very limited amount IPv6 neighbours (Juniper EX45x0 for example: 1000 NDP entries according to the datasheet). Given that each node needs at least two addresses (LLA+GUA), you won't need many nodes with multiple addresses before you start hitting some hard limitations. 11) Table 1: Might want to say "IA_NA/IA_TA" instead of just "IA_NA". 12) Table 1: The table says DHCPv6 IA_NA gives "unlimited" addressing while DHCPv6 PD does not. I think maybe it was meant to be the other way around? 13) Table 1: What's the difference between the rows «Stateful, request-based» and «Request-based» supposed to be? (You might want to take into account DAD for SLAAC in one of them, cf. point #4.) 14) Section 7 / Table 1: I think you should discuss whether or not an approach can be cascaded, or at least easily so. As an example, consider a 3GPP mobile network. It provides a /64, so it conforms with the recommendation in this document. However, if you use RFC7278 to create a tethering wireless network, a tethered host on that network cannot easily share that network further using because RFC7278 requires the upstream interface to be a point-to-point one, which the wirel ess network is not. 15) Section 8.1: «y large enterprise networks, including the enterprise networks of the authors, are fully dual-stack but do not use or support DHCPv6.». Not that there's anything wrong with this statement, it left me wondering: 1) How do you communicate DNS servers to your Windows hosts, assuming you have any? (Maybe you meant to say «does not use or support DHCPv6 *address assignment*»?) 2) What happens if you try to configure a gazillion addresses on your host when connected to this network? Does it actually work, does the network break, are (some of) the addresses rendered unusable and if so is it due to simultaneous addresses per host being limited somehow (hardware or policy) and if so what is that limitation exactly? 16) Section 8.2: «The total size of net 10 is roughly 2^24». Roughly? Isn't it *exactly* 2^24? 17) Section 8.2: The reference to RFC1918 should probably be, well, an (actual) reference. 18) Section 8.2: Echoing what Sander said, a /40 isn't easy to get as an enterprise (end-user), you'll need something like 128 sites for that or become your own LIR. I don't think saying you want to assign a /64 per host provides adequate justification for more than the standard /48 per site, at least not in the RIPE region. (But it is of course possible to do something about that.) 19) Section 8.2: «Currently, residential users receive one IPv4 address» - except that more and more of them are receiving *less than* one IPv4 address nowadays... 20) Sections 10, 11, A: Text that appears to be from a RFC template is left over. Tore
- [v6ops] new draft: draft-colitti-v6ops-host-addr-… fred
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Simon Perreault
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Sander Steffann
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Andrew Yourtchenko
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Fred Baker (fred)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Lorenzo Colitti
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Erik Kline
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Yury Shefer
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Tore Anderson
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Ray Hunter
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Erik Kline
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Tore Anderson
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Andrew 👽 Yourtchenko
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Hemant Singh (shemant)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Hemant Singh (shemant)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Brian E Carpenter
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Fred Baker (fred)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Brian E Carpenter
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Hemant Singh (shemant)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Sander Steffann
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Fred Baker (fred)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Tom Taylor
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Jouni Korhonen
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Erik Kline
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Alexandru Petrescu
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Mukom Akong T.
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Dave Thaler
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Mikael Abrahamsson
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Ross Chandler
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Mark Smith
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Lorenzo Colitti
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… George, Wes
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… George, Wes
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Mark Smith
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… George, Wes
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Templin, Fred L
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Lorenzo Colitti
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Fred Baker (fred)
- Re: [v6ops] new draft: draft-colitti-v6ops-host-a… Alexandru Petrescu