Re: [quicwg/base-drafts] Should we allow ACK-only packets to be declared lost? (#3451)

Kazuho Oku <notifications@github.com> Wed, 12 February 2020 04:15 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 33B5012006D for <quic-issues@ietfa.amsl.com>; Tue, 11 Feb 2020 20:15:29 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -6.382
X-Spam-Level:
X-Spam-Status: No, score=-6.382 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_IMAGE_ONLY_24=1.618, 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 CC26xBnwrmRo for <quic-issues@ietfa.amsl.com>; Tue, 11 Feb 2020 20:15:27 -0800 (PST)
Received: from out-17.smtp.github.com (out-17.smtp.github.com [192.30.252.200]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 0444A120058 for <quic-issues@ietf.org>; Tue, 11 Feb 2020 20:15:27 -0800 (PST)
Received: from github-lowworker-b19c547.va3-iad.github.net (github-lowworker-b19c547.va3-iad.github.net [10.48.17.66]) by smtp.github.com (Postfix) with ESMTP id 9AF0F6E13A7 for <quic-issues@ietf.org>; Tue, 11 Feb 2020 20:15:25 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=github.com; s=pf2014; t=1581480925; bh=6BeW1SFJ3FWx3sSV2fzxZs9JRH9747z3IIzZcZePGOw=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:List-ID: List-Archive:List-Post:List-Unsubscribe:From; b=hy8GkLNB/LYIWkMzoNIPMMW+oFDBsjaaJiLIIqQSB2FujvZlblX9+D3Mh16FKNg67 1VxFI5VkC1HphQSKrQQH+mrhMnzUAsUX35fn77NCPpdoviTw1d3sFtYrp9d8PCnwhc Czl8h52rC2JqDQdrvSJnTL8d8Mql3zwLj/24QhPw=
Date: Tue, 11 Feb 2020 20:15:25 -0800
From: Kazuho Oku <notifications@github.com>
Reply-To: quicwg/base-drafts <reply+AFTOJK4UKVCTLLZHOHJRRSF4KCXF3EVBNHHCDF6P4Q@reply.github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Cc: Subscribed <subscribed@noreply.github.com>
Message-ID: <quicwg/base-drafts/issues/3451/585019747@github.com>
In-Reply-To: <quicwg/base-drafts/issues/3451@github.com>
References: <quicwg/base-drafts/issues/3451@github.com>
Subject: Re: [quicwg/base-drafts] Should we allow ACK-only packets to be declared lost? (#3451)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5e437bdd8c024_5b53ff309ecd95c134324"; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: kazuho
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/FeEmJ-LUoPsF4ZMLsIHH6Ss7fig>
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: Wed, 12 Feb 2020 04:15:29 -0000

The problem is that a loss event has impact on CC, which applies to the amount of data the endpoint sends.

IIUC, the basis of CC is that an endpoint throttles the bandwidth *it* uses based on the loss rate of data *it* sent. However, generation of ACKs is not controlled by the endpoint. It's controlled by the peer.

Consider the case of in-flight wifi that uses a satellite link. The client (web browser) could be sending far more ACK-only packets than ACK-eliciting packets. In such case, I am concerned about the impact of taking loss of ACK-only packets into calculation.

-- 
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/issues/3451#issuecomment-585019747