From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x22f.google.com (mail-pf0-x22f.google.com [IPv6:2607:f8b0:400e:c00::22f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 55E7B3B2BC; Sat, 4 Jun 2016 16:56:45 -0400 (EDT) Received: by mail-pf0-x22f.google.com with SMTP id g64so54619511pfb.2; Sat, 04 Jun 2016 13:56:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:subject:from:to:cc:date:in-reply-to:references :mime-version:content-transfer-encoding; bh=C1DzvUwZ4FszeG2/U/+xvNmGegjBm31b1xYkLMCc0vk=; b=Ub+Qy5ftKy39OWFysmRab/FhuN1smbtQ/wI4+DZ3oGak+pb6xCWt6E4Cn/zYk78qHn /QmWlS7FhJHhzcfwci0GR9UzbuCxJHrFSI8Gpf4YG8rphLp3986M2MKuC22myUuz5m5k IpT8ZEu2N8K0WWjwIetZugrtYUKcu8XIzD1ZEyRPk4PPv24i4BLyWzII63oRSIoiTjy+ F0wIjj2EJ4AqaGhMSkx4WCBKTwYAOz9mp9Bwd8tk1AK3gjxWtjM6cyW9Gzx0vr/IN5e6 Wnd5UnN/dh6ALAPfWtAa3joRjHzkhevY55lLVIz4PBs74IhbxFhc+CCGqfnW2lm1PPT3 lVsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:mime-version:content-transfer-encoding; bh=C1DzvUwZ4FszeG2/U/+xvNmGegjBm31b1xYkLMCc0vk=; b=QLPFGtOPf3dbl/gmG4poTg/JFswdXE70IZsFmon3d6thEoydXFjb5DoQ056Topds+N RoI2zC2jFFwWW8IOdG7QM9oNhXcfWsoKsSacSrc8EuUqqMVJZBK+6Ykd4NguRST9qj8/ UPrM08SvZW6SoZKsKS3eq+BgCPCiaitg/ZBg8QJS9k0uU9t+w5j5KJP3pUlAYF7T5jeL /w0EmPeZcijdzC5pNPWZ151bafB3V+qyVyTXAXZ8cDMoYBTMD2FQcigJ87uuzZ8dzgnm BnlysEUHxy2MsJzSUXkDFDa3W5VstpFs46h+xtC+doz3i6uMbSM574Optohmi1bRqaeB SESw== X-Gm-Message-State: ALyK8tJzj1DZX+XMnXwEvdmj9C3+aKLMqUztj+vktKb8AdWNoOubA9hpxOdgDaUWjJaNmQ== X-Received: by 10.98.72.27 with SMTP id v27mr14522184pfa.143.1465073804464; Sat, 04 Jun 2016 13:56:44 -0700 (PDT) Received: from [172.29.162.28] ([172.29.162.28]) by smtp.googlemail.com with ESMTPSA id hz9sm14778764pac.13.2016.06.04.13.56.42 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 04 Jun 2016 13:56:43 -0700 (PDT) Message-ID: <1465073802.2968.21.camel@edumazet-glaptop3.roam.corp.google.com> From: Eric Dumazet To: Jonathan Morton Cc: Noah Causin , Andrew McGregor , cake@lists.bufferbloat.net, "codel@lists.bufferbloat.net" Date: Sat, 04 Jun 2016 13:56:42 -0700 In-Reply-To: References: <22371476-B45C-4E81-93C0-D39A67639EA0@gmx.de> <857AEE56-E7DB-4981-B32E-82473F877139@gmail.com> <8AB0D25D-C1CA-45F1-889E-2F73CF8C44F7@gmail.com> <323AFC22-A092-4F59-8197-AF21EF73FD58@gmail.com> <274D3A0FA900FD47AA6B56991AAA32FDC5529FC8@wtl-exchp-1.sandvine.com> <574478B4.7080103@taht.net> <39F38477-A877-4C1B-9B7F-BB3358425F17@gmail.com> <0eb223f9-2873-7f53-c2ce-c6867ddec17c@gmail.com> <48A25043-19E2-4BB7-B634-A4003F7BE6F8@gmail.com> <01BEA343-7C07-46FA-8DC4-07BF26309FC8@gmail.com> <10d58240-e106-ff1f-a038-df5bc0ee7a36@gmail.com> <1465062599.2968.11.camel@edumazet-glaptop3.roam.corp.google.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [Cake] [Codel] Proposing COBALT X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Jun 2016 20:56:45 -0000 On Sat, 2016-06-04 at 22:55 +0300, Jonathan Morton wrote: > > On 4 Jun, 2016, at 20:49, Eric Dumazet wrote: > > > > ECN (as in RFC 3168) is well known to be trivially exploited by peers > > pretending to be ECN ready, but not reacting to feedbacks, only to let > > their packets traverse congested hops with a lower drop probability. > > In this case it is the sender cheating, not the receiver, nor the > network. ECN Nonce doesn’t apply, as it is designed to protect > against the latter two forms of cheating (and in any case nobody ever > deployed it). Well, this is another demonstration of how ECN can be fooled, either by malicious peers (senders and/or receivers), or simply bugs in TOS byte remarking. Senders (or a buggy router) can mark all packets with ECT(0), regardless of ECN being negotiated at all in TCP 3WHS