Status of carl9170

Status of carl9170

[Thomas Novin]

Hello

I accidentally bought two TP-Link TL-WN821N v2 (accidentally because I
was going for v3). I've tried using them with compat-wireless (just now
tested with 2011-06-15) & the carl9170-driver.

When using these to connect to my Ubiquiti Power AP-N I get terrible
performance. Using another computer with some Broadcom 802.11g chip (b43
driver) it works OK.

For example, doing a 100 packet ping towards my LAN gateway and at the
same time trying to load a webpage.

--- 10.0.0.254 ping statistics ---
100 packets transmitted, 60 received, 40% packet loss, time 99229ms
rtt min/avg/max/mdev = 0.832/93.193/1264.009/292.193 ms, pipe 2

wlan0     IEEE 802.11bgn  ESSID:"POWERAPN"  
          Mode:Managed  Frequency:2.427 GHz  Access Point:
00:15:6D:9E:D2:A0
          Bit Rate=58.5 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=64/70  Signal level=-46 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:4  Invalid misc:0   Missed beacon:0

Being closer to the AP with better link quality  doesn't help at all.

Should I just get some other USB adapter or is there hope for the ones
that I have? If other, which ones are best supported? I really don't
care about GPL firmware, I just want stable & fast 802.11n performance.

Rgds//Thomas

Re: Status of carl9170

[Christian Lamparter]

On Thursday 16 June 2011 22:13:16 Thomas Novin wrote:
> When using these to connect to my Ubiquiti Power AP-N I get terrible
> performance. Using another computer with some Broadcom 802.11g chip (b43
> driver) it works OK.
> 
> For example, doing a 100 packet ping towards my LAN gateway and at the
> same time trying to load a webpage.
> 
> --- 10.0.0.254 ping statistics ---
> 100 packets transmitted, 60 received, 40% packet loss, time 99229ms
> rtt min/avg/max/mdev = 0.832/93.193/1264.009/292.193 ms, pipe 2

no problem, here's a ping -c 100 in my setup

--- 192.168.0.254 ping statistics ---
100 packets transmitted, 100 received, 0% packet loss, time 99138ms
rtt min/avg/max/mdev = 1.046/2.190/9.561/1.209 ms

But at least, you could try to disable the 11n cap by loading the module
with noht=1 and the hwcrypt by nohwcrypt=1.

Btw, do you have anything in your dmesg from the driver?

Regards,
	Chr

Re: Status of carl9170

[Thomas Novin]

On tor, 2011-06-16 at 22:49 +0200, Christian Lamparter wrote:
> But at least, you could try to disable the 11n cap by loading the module
> with noht=1 and the hwcrypt by nohwcrypt=1.
> 
> Btw, do you have anything in your dmesg from the driver?

Serious difference! Transferring files both tx/rx with scp at full speed
while doing ping results in decent transfer speeds and no packet loss.

>From dmesg: http://paste.ubuntu.com/628344/

Thanks,

Thomas

Re: Status of carl9170

[Christian Lamparter]

On Friday 17 June 2011 12:20:23 Thomas Novin wrote:
> On tor, 2011-06-16 at 22:49 +0200, Christian Lamparter wrote:
> > But at least, you could try to disable the 11n cap by loading the module
> > with noht=1 and the hwcrypt by nohwcrypt=1.
> > 
> > Btw, do you have anything in your dmesg from the driver?
> 
> Serious difference! Transferring files both tx/rx with scp at full speed
> while doing ping results in decent transfer speeds and no packet loss.
> 
> From dmesg: http://paste.ubuntu.com/628344/
Ok, can you please tell which option helped? If it was noht, then
you should check if there is a newer firmware for your router.

Regards,
	Chr

Re: Status of carl9170

[Thomas Novin]

On fre, 2011-06-17 at 12:52 +0200, Christian Lamparter wrote:
> On Friday 17 June 2011 12:20:23 Thomas Novin wrote:
> > On tor, 2011-06-16 at 22:49 +0200, Christian Lamparter wrote:
> > > But at least, you could try to disable the 11n cap by loading the module
> > > with noht=1 and the hwcrypt by nohwcrypt=1.
> > > 
> > > Btw, do you have anything in your dmesg from the driver?
> > 
> > Serious difference! Transferring files both tx/rx with scp at full speed
> > while doing ping results in decent transfer speeds and no packet loss.
> > 
> > From dmesg: http://paste.ubuntu.com/628344/
> Ok, can you please tell which option helped? If it was noht, then
> you should check if there is a newer firmware for your router.

Yes, it was noht that did the trick. Modprobing it with noht=1 and
nohwcrypt=0 I still had the problem.

There isn't any newer AirOS available, what is this about and how can I
describe it to the AP manufacturer if I report it as a bug?

Rgds//Thomas

Re: Status of carl9170

[Thomas Novin]

On fre, 2011-06-17 at 16:44 +0200, Thomas Novin wrote:
> > Ok, can you please tell which option helped? If it was noht, then
> > you should check if there is a newer firmware for your router.

I noticed that I only have 802.11b/g now, did noht disable 802.11n?

Rgds//Thomas

Re: Status of carl9170

[Christian Lamparter]

On Friday 17 June 2011 16:57:59 Thomas Novin wrote:
> On fre, 2011-06-17 at 16:44 +0200, Thomas Novin wrote:
> > > Ok, can you please tell which option helped? If it was noht, then
> > > you should check if there is a newer firmware for your router.
> 
> I noticed that I only have 802.11b/g now, did noht disable 802.11n?
exactly, this switch disables 11n in case there's a problem.

http://wireless.kernel.org/en/users/Drivers/carl9170#A802.11n_Compatibility

I wonder if there's an OpenWRT port for the AP you got ;)

Regards,
	Chr

Re: Status of carl9170

[Thomas Novin]

On Fri, Jun 17, 2011 at 11:10 PM, Christian Lamparter
<chunkeey@googlemail.com> wrote:
>> On fre, 2011-06-17 at 16:44 +0200, Thomas Novin wrote:
>> I noticed that I only have 802.11b/g now, did noht disable 802.11n?
> exactly, this switch disables 11n in case there's a problem.
>
> http://wireless.kernel.org/en/users/Drivers/carl9170#A802.11n_Compatibility
>
> I wonder if there's an OpenWRT port for the AP you got ;)
>

Ok.. I have just ordered another adapter (Sony UWA-BR100) and will try
that instead.

No OpenWRT for this AP..

Rgds//Thomas