Re: Re: More APs with single ­SSID

Milan Krčmář krcmar
Sun Jan 27 04:35:39 PST 2013

Yes, I have forgotten to emphasize that it is primarily STA's problem
and that I would like to discuss how to mitigate it from AP's point of
view, because you usually have not enough control over STAs: we
operate AP's that should work with usual STA implementations. We
observed Android phones behave slightly better than brand (HP etc.)
notebooks (mostly Intel radios)...

I think Intel radios/Windows driver must be capable of background
scanning, but they seem to prefer continuous (but slower) service to
roaming interruption. But too much.

Don't suppose disabling lower MCS would help. It might make the
problem even worse. But the 802.11k is promising... Thank you.

On Sun, Jan 27, 2013 at 12:43 PM,  <newuse at> wrote:
> I am not sure if it helps, but you could also try to disallow low MCSs...
> What version of supplicant are you using? Try to compile the latest of wpasupplicant, it was reported to be working even under Windows...
> IMHO, the problem is related to STA drivers and software. There should be support of the background monitoring...
> So the other way you already are using -- kicking STAs by low level...
> There was something interesting in 802.11k -- there is a possibility to collect some info from STAs via RADIUS, but I don't remember exactly, if it could be helpful in your case....
> ??? 27 ??? 2013 15:20:55 +0400, Milan Krm <krcmar at> ???????:
>> As far as I know, the 802.11r does not help to solve the problem
>> described. It will speed the handoff process up, but does not
>> influence STA's original decision to roam to another AP. My problem is
>> much more fundamental than this.
>> My problem occurs even in open networks without 802.11i. Imagine a
>> notebook (Wi-Fi STA) watching 10 Mbit HD video stream over HTTP with
>> client-side buffer of several seconds. When such a notebook moves to
>> another room and gets closer to another AP, the user would not mention
>> even a 3 seconds interruption of HTTP stream should the STA roam. But
>> the STA stays associated with the now weaker AP and must lower
>> modulation below 10 Mbit, so the stream stops playing when the buffer
>> gets emptied.
>> Milan
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>> HostAP mailing list
>> HostAP at
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