Re: [quicwg/base-drafts] ECN verification text (#2752)

mirjak <notifications@github.com> Fri, 02 August 2019 09:35 UTC

Return-Path: <noreply@github.com>
X-Original-To: quic-issues@ietfa.amsl.com
Delivered-To: quic-issues@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 18915120088 for <quic-issues@ietfa.amsl.com>; Fri, 2 Aug 2019 02:35:48 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -8
X-Spam-Level:
X-Spam-Status: No, score=-8 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=0.001, MAILING_LIST_MULTI=-1, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=github.com
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KrXbGjRYxPR2 for <quic-issues@ietfa.amsl.com>; Fri, 2 Aug 2019 02:35:46 -0700 (PDT)
Received: from out-9.smtp.github.com (out-9.smtp.github.com [192.30.254.192]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 2572812004E for <quic-issues@ietf.org>; Fri, 2 Aug 2019 02:35:46 -0700 (PDT)
Date: Fri, 02 Aug 2019 02:35:45 -0700
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=github.com; s=pf2014; t=1564738545; bh=Syb8kakSIgeJA5AyyI/6qRdXM/FpDpOkdqFPAbQsWpQ=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:List-ID: List-Archive:List-Post:List-Unsubscribe:From; b=gOodFfAjtklDC3vubTjElyJr5cWzZYhG4T70E81BZIcMP0t5SfURgwePZ3S8VoCa1 3CCZktGk7+utqRODzjgIh+0uqoNuEoPQZ+F3X7RIklwqt5fa1qeRislkoaYuLk7X9K FB0gX8zvNof26MeDR1vF1IZChqxClgV5gijlK6V4=
From: mirjak <notifications@github.com>
Reply-To: quicwg/base-drafts <reply+AFTOJK3EH5UELT6OUHERJMN3KE3HDEVBNHHBVKABIA@reply.github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Cc: Subscribed <subscribed@noreply.github.com>
Message-ID: <quicwg/base-drafts/pull/2752/review/270079868@github.com>
In-Reply-To: <quicwg/base-drafts/pull/2752@github.com>
References: <quicwg/base-drafts/pull/2752@github.com>
Subject: Re: [quicwg/base-drafts] ECN verification text (#2752)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5d4403f13d03e_363d3f9143acd9602589ec"; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: mirjak
X-GitHub-Recipient: quic-issues
X-GitHub-Reason: subscribed
X-Auto-Response-Suppress: All
X-GitHub-Recipient-Address: quic-issues@ietf.org
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic-issues/M0ug9o2wE2dIuOsRftuQGe4T_ks>
X-BeenThere: quic-issues@ietf.org
X-Mailman-Version: 2.1.29
List-Id: Notification list for GitHub issues related to the QUIC WG <quic-issues.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/quic-issues>, <mailto:quic-issues-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/quic-issues/>
List-Post: <mailto:quic-issues@ietf.org>
List-Help: <mailto:quic-issues-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/quic-issues>, <mailto:quic-issues-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 02 Aug 2019 09:35:48 -0000

mirjak commented on this pull request.



>  If verification fails, then the endpoint ceases setting ECT codepoints in
 subsequent IP packets with the expectation that either the network path or the
 peer does not support ECN.
 
-If an endpoint sets ECT codepoints on outgoing IP packets and encounters a
-retransmission timeout due to the absence of acknowledgments from the peer (see
-{{QUIC-RECOVERY}}), or if an endpoint has reason to believe that an element on
-the network path might be corrupting ECN codepoints, the endpoint MAY cease
-setting ECT codepoints in subsequent packets.  Doing so allows the connection to
-be resilient to network elements that corrupt ECN codepoints in the IP header or
-drop packets with ECT or CE codepoints in the IP header.
+If an ECT codepoint set is not dropped or corrupted by a network device, then a
+received packet contains either the codepoint sent by the peer or the Congestion
+Experienced (CE) codepoint set by a network device that is experiencing
+congestion.
+
+Upon successful verification, an endpoint continues to set ECT codepoints in
+subsequent packets with the expectation that the path is ECN-capable.

Under the assumption that ECN-based black holing basically doesn't exists anymore or at at least was not measurable anymore, I would like to propose to enable ECN-marking from the beginning and simply disable ECN on time-out or if acks without ECN feedback are received. Of course ECN could be enabled anytime again if you want to try again, however, no matter if in "testing" or not if you don't receive ECN feedback (anymore) for whatever reason, you should stop using ECN no matter what.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/quicwg/base-drafts/pull/2752#discussion_r310056524