[ath9k-devel] AR9280 and Packet Loss While Scanning

[ath9k-devel] AR9280 and Packet Loss While Scanning

[Matt Causey]

Hello,

I'm running linux 2.6.38.2, with wpa_supplicant 0.7.3, and the ar9280
wireless card.  We're using EAP-TLS in a large building with lots of
access points around on the same ssid.  We are pretty happy with our
tests so far, except for one thing.  Every time the client roams, we
end up with some packet loss.  It's not a lot, but usually a few
frames...enough that when we roam around the building for an hour we
end up at about 4% packet loss.  It is enough that we're comparing the
clients to others like Mac and Windows clients, and those other
clients work without packet loss in the same scenarios.

There are some practical reasons for this, since when the card is
scanning, it is obvious that it is not passing traffic, or at the very
least traffic is delayed.  So, I was wondering, are there enhancements
in the latest kernel that could help speed up scanning, or reduce
packet loss?

Thanks,

--
Matt

[ath9k-devel] AR9280 and Packet Loss While Scanning

[Manuel Sáez]

You could take a look to PRP to avoid packet loss when roaming. It may help you.

http://www.ines.zhaw.ch/en/engineering/ines/high-availability/prp/solutions/software-stack.html

Regards,

2011/9/30 Matt Causey <matt.causey@gmail.com>:
> Hello,
>
> I'm running linux 2.6.38.2, with wpa_supplicant 0.7.3, and the ar9280
> wireless card. ?We're using EAP-TLS in a large building with lots of
> access points around on the same ssid. ?We are pretty happy with our
> tests so far, except for one thing. ?Every time the client roams, we
> end up with some packet loss. ?It's not a lot, but usually a few
> frames...enough that when we roam around the building for an hour we
> end up at about 4% packet loss. ?It is enough that we're comparing the
> clients to others like Mac and Windows clients, and those other
> clients work without packet loss in the same scenarios.
>
> There are some practical reasons for this, since when the card is
> scanning, it is obvious that it is not passing traffic, or at the very
> least traffic is delayed. ?So, I was wondering, are there enhancements
> in the latest kernel that could help speed up scanning, or reduce
> packet loss?
>
> Thanks,
>
> --
> Matt
> _______________________________________________
> ath9k-devel mailing list
> ath9k-devel at lists.ath9k.org
> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
>

[ath9k-devel] AR9280 and Packet Loss While Scanning

[Matt Causey]

Right, but Windows and Mac wireless clients don't need an additional
software stack to prevent packet loss from happening on their wireless
cards.  Is this a way of saying that we should expect 3-4% packet loss
with ath9k?  Is there any data I could collect that could give me
visibility into where on the stack the traffic is lost?

--
Matt


On Fri, Oct 7, 2011 at 1:01 AM, Manuel S?ez <manuelsaezr@gmail.com> wrote:
> You could take a look to PRP to avoid packet loss when roaming. It may help you.
>
> http://www.ines.zhaw.ch/en/engineering/ines/high-availability/prp/solutions/software-stack.html
>
> Regards,
>
> 2011/9/30 Matt Causey <matt.causey@gmail.com>:
>> Hello,
>>
>> I'm running linux 2.6.38.2, with wpa_supplicant 0.7.3, and the ar9280
>> wireless card. ?We're using EAP-TLS in a large building with lots of
>> access points around on the same ssid. ?We are pretty happy with our
>> tests so far, except for one thing. ?Every time the client roams, we
>> end up with some packet loss. ?It's not a lot, but usually a few
>> frames...enough that when we roam around the building for an hour we
>> end up at about 4% packet loss. ?It is enough that we're comparing the
>> clients to others like Mac and Windows clients, and those other
>> clients work without packet loss in the same scenarios.
>>
>> There are some practical reasons for this, since when the card is
>> scanning, it is obvious that it is not passing traffic, or at the very
>> least traffic is delayed. ?So, I was wondering, are there enhancements
>> in the latest kernel that could help speed up scanning, or reduce
>> packet loss?
>>
>> Thanks,
>>
>> --
>> Matt
>> _______________________________________________
>> ath9k-devel mailing list
>> ath9k-devel at lists.ath9k.org
>> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
>>
>