Re: [quicwg/base-drafts] Recovery: when PTO expires and no data to send (#3286)

ianswett <> Thu, 05 December 2019 22:05 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id A1A4F1200EF for <>; Thu, 5 Dec 2019 14:05:30 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -6.454
X-Spam-Status: No, score=-6.454 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_20=1.546, 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: (amavisd-new); dkim=pass (1024-bit key)
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id V_Ld6AE1Qqnn for <>; Thu, 5 Dec 2019 14:05:29 -0800 (PST)
Received: from ( []) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 6F7ED120073 for <>; Thu, 5 Dec 2019 14:05:29 -0800 (PST)
Date: Thu, 05 Dec 2019 14:05:28 -0800
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=pf2014; t=1575583529; bh=A0EhcyXXhFB2JoRXKCl/dQeyzVjpj8BmQ79xs1BqUqk=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:List-ID: List-Archive:List-Post:List-Unsubscribe:From; b=14xzeCe/t0afRSpu7eieNdpwWaZHXrha0FHrLJM66Jv9iRF6HJUonp6bQwa/IopnP JJOpzAifKTQkZ6c6koF2nIWfdLmtlEEy9xcIFZOPH6n68LB28I8qcDLQNfXCZ3tvoe zgMwgWteDShYih2RIMNNXFEZR3oyQQDtO+bAfNf4=
From: ianswett <>
Reply-To: quicwg/base-drafts <>
To: quicwg/base-drafts <>
Cc: Subscribed <>
Message-ID: <quicwg/base-drafts/issues/3286/>
In-Reply-To: <quicwg/base-drafts/issues/>
References: <quicwg/base-drafts/issues/>
Subject: Re: [quicwg/base-drafts] Recovery: when PTO expires and no data to send (#3286)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5de97f28c799a_3b103fa4886cd95c87041"; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: ianswett
X-GitHub-Recipient: quic-issues
X-GitHub-Reason: subscribed
X-Auto-Response-Suppress: All
Archived-At: <>
X-Mailman-Version: 2.1.29
List-Id: Notification list for GitHub issues related to the QUIC WG <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Thu, 05 Dec 2019 22:05:30 -0000

This exponential backoff of PING packets is less wasteful than a TCP RTO, since in TCP one can't decide not to retransmit data that was previously sent.  It's also an edge case which rarely occurs in practice.

In order to detect persistent congestion correctly, you'll likely need to send multiple PINGs in this case.

Given the above, I'm happy with the current algorithm.

You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub: