Re: [aqm] TCP ACK Suppression

David Lang <david@lang.hm> Wed, 07 October 2015 17:19 UTC

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From: David Lang <david@lang.hm>
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To: Mikael Abrahamsson <swmike@swm.pp.se>
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Subject: Re: [aqm] TCP ACK Suppression
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On Wed, 7 Oct 2015, Mikael Abrahamsson wrote:

>> 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...
>
> Personally, I think you're going to see more and more of this. There are 
> mulitple shared access medium where you're allowed to send only part of the 
> time, and it's someone else who tells you when you may send.

it doesn't even require that someone else tells you when you may send. It can 
just be waiting for an available transmit timeslot (Wifi for example)

collapsing multiple ACKs that are going to be sent at once is almost always 
going to be a win.

David Lang