Re: [aqm] TCP ACK Suppression

Christian Huitema <> Fri, 09 October 2015 00:22 UTC

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From: Christian Huitema <>
To: David Lang <>, Joe Touch <>
Thread-Topic: [aqm] TCP ACK Suppression
Date: Fri, 9 Oct 2015 00:21:52 +0000
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Cc: "LAUTENSCHLAEGER, Wolfram \(Wolfram\)" <>, Greg White <>, "" <>
Subject: Re: [aqm] TCP ACK Suppression
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All that discussion is fun, but we should be careful to stay within the respective group charters.

As far as AQM is concerned, the question is whether the group wants to standardize some kind of special handling of TCP ACK as part of queue management. As far as the IETF rules are concerned, the answer is clearly NO -- we cannot create an IETF recommendation that breaks other IETF recommendations. Besides, such rules would not be very effective if the transport protocol is encrypted, as for example QUIC, or SCTP over DTLS. AQM should certainly not depend on end-systems not using encryption.

As for TCP and other protocols, the question is whether they should pay more attention to the volume of ACK and other control packets. The deployment of queue management systems like FQ-CODEL actually creates an incentive to do that, because a transport protocol that creates congestion on its uplink will be automatically penalized. But that discussion belongs in TCPM and other transport working groups, not AQM.

-- Christian Huitema