IETF Logo Mail Archive

Re: [ledbat] list of reasons for needing multiple TCP connections

Joe Touch <touch@ISI.EDU> Thu, 20 November 2008 20:44 UTC

Return-Path: <ledbat-bounces@ietf.org>
X-Original-To: tana-archive@ietf.org
Delivered-To: ietfarch-tana-archive@core3.amsl.com
Received: from [127.0.0.1] (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 47D813A6A2A; Thu, 20 Nov 2008 12:44:45 -0800 (PST)
X-Original-To: ledbat@core3.amsl.com
Delivered-To: ledbat@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 60B9A28C234 for <ledbat@core3.amsl.com>; Thu, 20 Nov 2008 12:44:44 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.569
X-Spam-Level:
X-Spam-Status: No, score=-2.569 tagged_above=-999 required=5 tests=[AWL=0.030, BAYES_00=-2.599]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 22j8hNMRufb0 for <ledbat@core3.amsl.com>; Thu, 20 Nov 2008 12:44:43 -0800 (PST)
Received: from vapor.isi.edu (vapor.isi.edu [128.9.64.64]) by core3.amsl.com (Postfix) with ESMTP id AEBC928C156 for <ledbat@ietf.org>; Thu, 20 Nov 2008 12:44:43 -0800 (PST)
Received: from [130.129.94.243] ([130.129.94.243]) by vapor.isi.edu (8.13.8/8.13.8) with ESMTP id mAKKiQbb012524 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 20 Nov 2008 12:44:29 -0800 (PST)
Message-ID: <4925CC2A.9080606@isi.edu>
Date: Thu, 20 Nov 2008 12:44:26 -0800
From: Joe Touch <touch@ISI.EDU>
User-Agent: Thunderbird 2.0.0.18 (Windows/20081105)
MIME-Version: 1.0
To: "Kartik Chandrayana (karchand)" <karchand@cisco.com>
References: <4925BDEE.6090101@isi.edu> <8c99930d0811201206yb0ef259v28c361438cb14773@mail.gmail.com> <A0988C2F192F124FAFE3D70264C04587077A12EC@xmb-sjc-231.amer.cisco.com>
In-Reply-To: <A0988C2F192F124FAFE3D70264C04587077A12EC@xmb-sjc-231.amer.cisco.com>
X-Enigmail-Version: 0.95.7
X-ISI-4-43-8-MailScanner: Found to be clean
X-MailScanner-From: touch@isi.edu
Cc: ledbat@ietf.org
Subject: Re: [ledbat] list of reasons for needing multiple TCP connections
X-BeenThere: ledbat@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: Mailing list of the LEDBAT WG <ledbat.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/ledbat>, <mailto:ledbat-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/pipermail/ledbat>
List-Post: <mailto:ledbat@ietf.org>
List-Help: <mailto:ledbat-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ledbat>, <mailto:ledbat-request@ietf.org?subject=subscribe>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: ledbat-bounces@ietf.org
Errors-To: ledbat-bounces@ietf.org

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1



Kartik Chandrayana (karchand) wrote:
> Andy, Joe:
> 
> One reason I can think of using multiple TCP connections is to overcome
> the non-negotiation of window-scale parameter on most boxes. With
> default window scale parameters, i.e 0, the congestion window is limited
> to 64KB only and thus for any pipe with bandwidth-delay-product greater
> than 64KB, a single TCP connection cannot keep the pipe full. In such a
> case, it would be beneficial to have multiple TCP connections. 
> 
> Also, since TCP design was mostly with single cpu in mind, I think
> multiple TCP connections can harness the multi-cpu architectures better
> than a single lean fast TCP.

That presumes that the OS implements parallelization in the network
code; I don't know if that's recently offered, but it has been the
sticking point in the past.

Joe
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkklzCoACgkQE5f5cImnZrt8lQCcDHUECfyDkJFHy8kXSSSI5gPE
tEEAnAhQv1XX45F/TfCqGXZgrDoo7ed9
=JSeb
-----END PGP SIGNATURE-----
_______________________________________________
ledbat mailing list
ledbat@ietf.org
https://www.ietf.org/mailman/listinfo/ledbat

v2.23.0 | Report a Bug | By Email