Re: [tcpm] Extending TCP option space

William Allen Simpson <william.allen.simpson@gmail.com> Wed, 31 August 2011 18:11 UTC

Return-Path: <william.allen.simpson@gmail.com>
X-Original-To: tcpm@ietfa.amsl.com
Delivered-To: tcpm@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id F020821F8E62 for <tcpm@ietfa.amsl.com>; Wed, 31 Aug 2011 11:11:41 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.42
X-Spam-Level:
X-Spam-Status: No, score=-3.42 tagged_above=-999 required=5 tests=[AWL=0.179, BAYES_00=-2.599, RCVD_IN_DNSWL_LOW=-1]
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 jQ46CvsCqbOr for <tcpm@ietfa.amsl.com>; Wed, 31 Aug 2011 11:11:41 -0700 (PDT)
Received: from mail-yi0-f44.google.com (mail-yi0-f44.google.com [209.85.218.44]) by ietfa.amsl.com (Postfix) with ESMTP id C49FF21F8E2F for <tcpm@ietf.org>; Wed, 31 Aug 2011 11:11:33 -0700 (PDT)
Received: by yie12 with SMTP id 12so993402yie.31 for <tcpm@ietf.org>; Wed, 31 Aug 2011 11:13:03 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=p0rglDNr3FhuBVfwCajTBA32Ao7bgRtACH0wjmeXKvE=; b=LQ744dLqy45y8Oxgsv+IvcDvYAR7/Q+LfQ3AfE3+w1ugz2bMlHDWVeQZT6wMTCeKnV gXXKUTr6yQUh1n+peSP6j1HVoRwDYMGwuWm9l/Hapu3r7cimCSNmFlW+DG88lRLCdXh5 GgR8zSSKjCAhvhUNfcDGyr3GzDeHqn0N3iPfo=
Received: by 10.236.185.138 with SMTP id u10mr3961822yhm.67.1314814383659; Wed, 31 Aug 2011 11:13:03 -0700 (PDT)
Received: from Wastrel-3.local (c-68-40-194-239.hsd1.mi.comcast.net [68.40.194.239]) by mx.google.com with ESMTPS id a29sm1488851yhj.59.2011.08.31.11.13.01 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 31 Aug 2011 11:13:02 -0700 (PDT)
Message-ID: <4E5E79AC.6030605@gmail.com>
Date: Wed, 31 Aug 2011 14:13:00 -0400
From: William Allen Simpson <william.allen.simpson@gmail.com>
User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.21) Gecko/20110830 Thunderbird/3.1.13
MIME-Version: 1.0
To: Pasi Sarolahti <pasi.sarolahti@iki.fi>
References: <9605EAA4-F1C4-4D83-B76E-88C81BFE1555@iki.fi>
In-Reply-To: <9605EAA4-F1C4-4D83-B76E-88C81BFE1555@iki.fi>
Content-Type: text/plain; charset="ISO-8859-1"; format="flowed"
Content-Transfer-Encoding: 7bit
Cc: tcpm@ietf.org
Subject: Re: [tcpm] Extending TCP option space
X-BeenThere: tcpm@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: TCP Maintenance and Minor Extensions Working Group <tcpm.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/tcpm>, <mailto:tcpm-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/tcpm>
List-Post: <mailto:tcpm@ietf.org>
List-Help: <mailto:tcpm-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tcpm>, <mailto:tcpm-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 31 Aug 2011 18:11:42 -0000

On 8/31/11 9:57 AM, Pasi Sarolahti wrote:
> TCP's option space has been under increasing demand recently, with new option-space hungry extensions such as MPTCP, and some recent ideas in the research domain. In the past there have been some discussion about mechanisms to extend the option space, and an extension option was proposed in draft-eddy-tcp-loo, but since then these efforts have died down. I'm wondering if there would be any interest in the tcpm community to resume this work.
>
Already done, already tested.  RFC-6013.


> I recall that re-segmenting middleboxes were mentioned as one potential problem for such extension, and there might be other problems. Nevertheless, I would find it useful, if there was an RFC that a) documented the known problems with option space extension; and b) defined an option format and assigned the needed type codes, to enable experimentations with larger than 40-byte option space.
>
I'm using options 31 and 32.  See
   https://tools.ietf.org/html/draft-simpson-tcpct-api-04


> Thoughts?
>
Always happy to have additional experimenters.  Not talkers, implementers.