[tcpm] New Version Notification for draft-zimmermann-tcp-lcd-02
Alexander Zimmermann <alexander.zimmermann@nets.rwth-aachen.de> Wed, 26 August 2009 14:13 UTC
Return-Path: <alexander.zimmermann@nets.rwth-aachen.de>
X-Original-To: tcpm@core3.amsl.com
Delivered-To: tcpm@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 6E3AF3A6BBD for <tcpm@core3.amsl.com>; Wed, 26 Aug 2009 07:13:32 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.41
X-Spam-Level:
X-Spam-Status: No, score=-4.41 tagged_above=-999 required=5 tests=[AWL=0.391, BAYES_00=-2.599, HELO_EQ_DE=0.35, HELO_MISMATCH_DE=1.448, RCVD_IN_DNSWL_MED=-4]
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 0JE+3045inwI for <tcpm@core3.amsl.com>; Wed, 26 Aug 2009 07:13:31 -0700 (PDT)
Received: from mta-2.ms.rz.rwth-aachen.de (mta-2.ms.rz.RWTH-Aachen.DE [134.130.7.73]) by core3.amsl.com (Postfix) with ESMTP id 0FFE23A6A8B for <tcpm@ietf.org>; Wed, 26 Aug 2009 07:12:37 -0700 (PDT)
MIME-version: 1.0
Received: from ironport-out-1.rz.rwth-aachen.de ([134.130.5.40]) by mta-2.ms.rz.RWTH-Aachen.de (Sun Java(tm) System Messaging Server 6.3-7.04 (built Sep 26 2008)) with ESMTP id <0KOZ0061PKHX0B10@mta-2.ms.rz.RWTH-Aachen.de> for tcpm@ietf.org; Wed, 26 Aug 2009 15:37:09 +0200 (CEST)
X-IronPort-AV: E=Sophos; i="4.44,279,1249250400"; d="sig'?scan'208"; a="23747586"
Received: from smarthost-2.ms.rz.rwth-aachen.de (HELO smarthost.rwth-aachen.de) ([134.130.7.90]) by ironport-in-1.rz.rwth-aachen.de with ESMTP; Wed, 26 Aug 2009 15:37:09 +0200
Received: from miami.nets.RWTH-Aachen.DE (miami.nets.RWTH-Aachen.DE [137.226.12.180]) by smarthost.rwth-aachen.de (8.13.8+Sun/8.13.8/1) with ESMTP id n7QDb96T010670 for <tcpm@ietf.org>; Wed, 26 Aug 2009 15:37:09 +0200 (CEST)
Message-id: <C6D4D39B-2E9B-4D88-A4A4-15908B503BB5@nets.rwth-aachen.de>
From: Alexander Zimmermann <alexander.zimmermann@nets.rwth-aachen.de>
To: tcpm@ietf.org
Content-type: multipart/signed; protocol="application/pgp-signature"; micalg="pgp-sha1"; boundary="Apple-Mail-11-256207881"
Content-transfer-encoding: 7bit
Date: Wed, 26 Aug 2009 15:37:11 +0200
X-Pgp-Agent: GPGMail 1.2.0 (v56)
X-Mailer: Apple Mail (2.936)
Subject: [tcpm] New Version Notification for draft-zimmermann-tcp-lcd-02
X-BeenThere: tcpm@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: TCP Maintenance and Minor Extensions Working Group <tcpm.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/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, 26 Aug 2009 14:13:32 -0000
Hi folks, I upload a new version of our draft to the IETF repository: http://www.ietf.org/internet-drafts/draft-zimmermann-tcp-lcd-02.txt As always, comments are more than welcome. Alex --- Main change from draft-zimmermann-tcp-lcd-01 The algorithm in Section 4.2 was slightly changed. Instead of reverting the RTO by halving it, it is recalculated with help of the "Backoff_cnt" variable. This fixes an issue that occurred when the retransmission timer was backed off but bounded by a maximum value. The algorithm in the previous version of the draft, would have "reverted" to half of that maximum value, instead of using the value, before the RTO was doubled (and then bounded). --- Filename: draft-zimmermann-tcp-lcd Revision: 02 Title: Make TCP more Robust to Long Connectivity Disruptions Creation_date: 2009-08-26 WG ID: Independent Submission Number_of_pages: 17 Abstract: Disruptions in end-to-end path connectivity which last longer than one retransmission timeout cause suboptimal TCP performance. The reason for the performance degradation is that TCP interprets segment loss induced by connectivity disruptions as a sign of congestion, resulting in repeated backoffs of the retransmission timer. This leads in turn to a deferred detection of the re-establishment of the connection since TCP waits until the next retransmission timeout occurs before attempting the retransmission. This document describes how standard ICMP messages can be exploited to disambiguate true congestion loss from non-congestion loss caused by long connectivity disruptions. Moreover, a revert strategy of the retransmission timer is specified that enables a more prompt detection of whether the connectivity to a previously disconnected peer node has been restored or not. The specified algorithm is a TCP sender-only modification that effectively improves TCP performance in presence of connectivity disruptions. // // Dipl.-Inform. Alexander Zimmermann // Department of Computer Science, Informatik 4 // RWTH Aachen University // Ahornstr. 55, 52056 Aachen, Germany // phone: (49-241) 80-21422, fax: (49-241) 80-22220 // email: zimmermann@cs.rwth-aachen.de // web: http://www.umic-mesh.net //
- [tcpm] New Version Notification for draft-zimmerm… Alexander Zimmermann
- Re: [tcpm] New Version Notification for draft-zim… Ilpo Järvinen
- Re: [tcpm] New Version Notification for draft-zim… Zimmermann Alexander