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Date: Sun, 26 Nov 2017 12:54:04 +0100
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
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Subject: Re: [Bloat] Steam In Home Streaming on ath9k wifi
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On Sun, Nov 26, 2017 at 11:53:04AM +0100, Jan Ceuleers wrote:
>> Another explanation for latency spikes on the order of 100ms is that a
>> periodic (and wholly unnecessary) scan for other APs is run, which
>> requires the wifi radio to be temporarily tuned away from the currently
>> associated AP's frequency.
> My understanding is that APs that operate on channels that are wider
> than 20MHz must back off to 20MHz in case they detect other SSIDs that
> are competing for the wider channel.

It's not about the AP, it's about the client. (APs can detect extension
channel interference without doing a scan, although I don't know if you need
this fallback at all on 5 GHz.)

/* Steinar */
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Homepage: https://www.sesse.net/