Re: [quicwg/base-drafts] ACKing ACK (#291)

Martin Thomson <notifications@github.com> Sun, 12 February 2017 23:49 UTC

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Date: Sun, 12 Feb 2017 15:49:04 -0800
From: Martin Thomson <notifications@github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Message-ID: <quicwg/base-drafts/issues/291/279264415@github.com>
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References: <quicwg/base-drafts/issues/291@github.com>
Subject: Re: [quicwg/base-drafts] ACKing ACK (#291)
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So the current text recommends throttling back on ACK when you are sending lots of packets.  The 20 packet thing keeps the rate low, but it is too arbitrary.  I can justify sending an ACK when you have other things to send, I can justify slowing the rate of ACK generation when you have nothing of value to acknowledge, but I can't justify the specific number.  Anything above 1 probably has the desired effect.

If you aren't careful, PING can waste time and bandwidth, especially since it demands access to the fast path.  Limiting the number that you will respond to is a DoS mitigation.

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