From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755485AbYKGEto (ORCPT ); Thu, 6 Nov 2008 23:49:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751467AbYKGEtb (ORCPT ); Thu, 6 Nov 2008 23:49:31 -0500 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:47572 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751353AbYKGEta (ORCPT ); Thu, 6 Nov 2008 23:49:30 -0500 Date: Thu, 06 Nov 2008 20:49:29 -0800 (PST) Message-Id: <20081106.204929.161401868.davem@davemloft.net> To: swmike@swm.pp.se Cc: daniel.blueman@gmail.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-net@vger.kernel.org Subject: Re: time for TCP ECN defaulting to on? From: David Miller In-Reply-To: References: <20081105.151015.206163697.davem@davemloft.net> X-Mailer: Mew version 6.1 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikael Abrahamsson Date: Fri, 7 Nov 2008 05:46:28 +0100 (CET) > I see that in > > there is a recommendation to not use ECN on retransmits, is there > code right now (or planned) to do some kind of "ECN blackhole > detection", ie if no response is received to SYN with ECN set, > continue by sending the second SYN without ECN and keep this > information for the duration of the TCP session? No, we are firmly against any form of ECN blackhole detection. Alexey Kuznetsov and Sally Floyd argued this out exhaustively several years ago.