Re: [aqm] TCP ACK Suppression

"Bless, Roland (TM)" <roland.bless@kit.edu> Wed, 07 October 2015 08:16 UTC

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To: "LAUTENSCHLAEGER, Wolfram (Wolfram)" <wolfram.lautenschlaeger@alcatel-lucent.com>, Greg White <g.white@CableLabs.com>, "aqm@ietf.org" <aqm@ietf.org>
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From: "Bless, Roland (TM)" <roland.bless@kit.edu>
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Subject: Re: [aqm] TCP ACK Suppression
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Hi,

Am 07.10.2015 um 09:42 schrieb LAUTENSCHLAEGER, Wolfram (Wolfram):
> Is this specialized upstream TCP ACK handling, particularly the
> prioritization a general recommendation in all access technologies? 
> Perhaps it should be, since otherwise up and downstream TCP flows interfere
> in a crazy queue oscillation that is typically misinterpreted by AQMs.
> Is this topic addressed in some RFC already?

Oh, I hope that this is an exception. Such kind of
optimizations may cause a lot of trouble since a link
layer device is interfering with transport layer semantics.
We all know that exactly these kinds of interference
eventually end up in problems with end-to-end transparency and
deployment of new protocol options. At least it interferes with
the ACK clocking expectation of some congestion control algorithms...

Regards,
 Roland