Re: [mpls] Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS in UDP) to Proposed Standard

<l.wood@surrey.ac.uk> Tue, 14 January 2014 08:33 UTC

Return-Path: <l.wood@surrey.ac.uk>
X-Original-To: mpls@ietfa.amsl.com
Delivered-To: mpls@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 3AEA31AE01D; Tue, 14 Jan 2014 00:33:09 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: 0.189
X-Spam-Level:
X-Spam-Status: No, score=0.189 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, CN_BODY_35=0.339, MIME_CHARSET_FARAWAY=2.45, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001, UNPARSEABLE_RELAY=0.001] 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 iU0vtlwPB9Fu; Tue, 14 Jan 2014 00:33:06 -0800 (PST)
Received: from mail1.bemta3.messagelabs.com (mail1.bemta3.messagelabs.com [195.245.230.164]) by ietfa.amsl.com (Postfix) with ESMTP id 3CF011ACCE9; Tue, 14 Jan 2014 00:33:05 -0800 (PST)
Received: from [195.245.230.131:6188] by server-4.bemta-3.messagelabs.com id 3D/0C-10414-536F4D25; Tue, 14 Jan 2014 08:32:53 +0000
X-Env-Sender: l.wood@surrey.ac.uk
X-Msg-Ref: server-6.tower-78.messagelabs.com!1389688372!33605148!1
X-Originating-IP: [131.227.200.31]
X-StarScan-Received:
X-StarScan-Version: 6.9.16; banners=-,-,-
X-VirusChecked: Checked
Received: (qmail 23810 invoked from network); 14 Jan 2014 08:32:52 -0000
Received: from exht011p.surrey.ac.uk (HELO EXHT011P.surrey.ac.uk) (131.227.200.31) by server-6.tower-78.messagelabs.com with AES128-SHA encrypted SMTP; 14 Jan 2014 08:32:52 -0000
Received: from EXMB01CMS.surrey.ac.uk ([169.254.1.204]) by EXHT011P.surrey.ac.uk ([131.227.200.31]) with mapi; Tue, 14 Jan 2014 08:32:52 +0000
From: l.wood@surrey.ac.uk
To: jmh@joelhalpern.com, lars@netapp.com, xuxiaohu@huawei.com
Date: Tue, 14 Jan 2014 08:28:05 +0000
Thread-Topic: Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS in UDP) to Proposed Standard
Thread-Index: Ac8OGeG46c8oWHrkQO+L1tKxoi92vgC6Kp6g
Message-ID: <290E20B455C66743BE178C5C84F1240847E63346C3@EXMB01CMS.surrey.ac.uk>
References: <20140102151419.4692.48031.idtracker@ietfa.amsl.com> <5933BB7D-2D2D-4145-A0B2-E92C8DA25844@netapp.com> <1FEE3F8F5CCDE64C9A8E8F4AD27C19EE08242A8E@NKGEML512-MBS.china.huawei.com> <43B89809-F517-4BE2-BE1B-748A4B78FC7F@netapp.com>, <52D01383.2080509@joelhalpern.com>
In-Reply-To: <52D01383.2080509@joelhalpern.com>
Accept-Language: en-US, en-GB
Content-Language: en-GB
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
acceptlanguage: en-US, en-GB
Content-Type: text/plain; charset="gb2312"
Content-Transfer-Encoding: base64
MIME-Version: 1.0
Cc: mpls@ietf.org, ietf@ietf.org
Subject: Re: [mpls] Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS in UDP) to Proposed Standard
X-BeenThere: mpls@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Multi-Protocol Label Switching WG <mpls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mpls>, <mailto:mpls-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/mpls/>
List-Post: <mailto:mpls@ietf.org>
List-Help: <mailto:mpls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 14 Jan 2014 08:33:09 -0000

It stands to reason that if tunnelers can turn off udp checksums
because their performance is degraded, they can turn off
congestion control because it will degrade their performance.

Rest of the internet getting congested and getting
misdelivered corrupted packets? Really not their problem.

There are important vendors trying to sell products here,
and they need performance to do so.
Get with the program!

Lloyd Wood
http://about.me/lloydwood
________________________________________
From: ietf [ietf-bounces@ietf.org] On Behalf Of Joel M. Halpern [jmh@joelhalpern.com]
Sent: 10 January 2014 15:36
To: Eggert, Lars; Xuxiaohu
Cc: mpls@ietf.org; IETF
Subject: Re: Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS in UDP) to Proposed Standard

Maybe I am completely missing things, but this looks wrong.
If the MPLS LSP is carrying fixed rate pseudo-wires, adding congestion
control will make it more likely that the service won't work.  Is that
really the goal?

We do not perform congestion control on MPLS LSPs.
Assuming that a UDP tunnel is carrying just MPLS and was established
just for MPLS, why would we expect it to behave differently than an MPLS
LSP running over the exact same path, carrying the exact same traffic?

Yours,
Joel

On 1/10/14 3:47 AM, Eggert, Lars wrote:
> Hi,
>
> that sounds good. What congestion control are you going to be specifying for your tunnel?
>
> Lars
>
> On 2014-1-10, at 4:46, Xuxiaohu <xuxiaohu@huawei.com> wrote:
>
>> Hi Lars,
>>
>> Thanks a lot for your comments.
>>
>> I wonder whether the following modified text for Congestion Consideration section is OK from your point of view:
>>
>> Since the MPLS-in-UDP encapsulation causes MPLS packets to be forwarded through "UDP tunnels", the congestion control guidelines for UDP tunnels as defined in Section 3.1.3 of [RFC5405] SHOULD be followed. Specifically, MPLS can carry a number of different protocols as payloads. When the payload traffic is IP-based and congestion-controlled, the UDP tunnel SHOULD NOT employ its own congestion control mechanism, because congestion losses of tunneled traffic will already trigger an appropriate congestion response at the original senders of the tunneled traffic. When the payload traffic is not known to be IP-based, or is known to be IP-based but not congestion-controlled, the UDP tunnel SHOULD employ an appropriate congestion control mechanism. Furthermore, because UDP tunnels are usually bulk-transfer applications as far as the intermediate routers are concerned, the guidelines as defined in Section 3.1.1 of [RFC5405] SHOULD apply.
>>
>> Best regards,
>> Xiaohu
>>
>>> -----邮件原件-----
>>> 发件人: mpls [mailto:mpls-bounces@ietf.org] 代表 Eggert, Lars
>>> 发送时间: 2014年1月8日 18:22
>>> 收件人: IETF
>>> 抄送: mpls@ietf.org
>>> 主题: Re: [mpls] Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS
>>> in UDP) to Proposed Standard
>>>
>>> Hi,
>>>
>>> On 2014-1-2, at 16:14, The IESG <iesg-secretary@ietf.org> wrote:
>>>> - 'Encapsulating MPLS in UDP'
>>>> <draft-ietf-mpls-in-udp-04.txt> as Proposed Standard
>>>
>>>
>>> this document needs to describe how it addresses the issues raised in BCP145
>>> (RFC5405). It already contains some text about messages sizes and congestion
>>> considerations, which is great. Unfortunately, the text about congestion
>>> considerations is not fully in line with RFC5405.
>>>
>>> Lars
>