Strange txpower behavior (setting too high for 2 cards and not high enough for one)

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2013-03-29
xsspants

Strange txpower behavior (setting too high for 2 cards and not high enough for one)

After setting reg domain to BO:
An Alfa AWUS036NH behaves normally. Sets itself to 30dBm. WON'T allow setting to 33, which it's specced for.
A Buffalo WLI-UC-GNHP allows me to set it to 30dBm, which can't be right for such a tiny dongle.
An Alfa AWUS036EW allows setting to 30dBm as well. When it's marketed max is 27dBm (500mw)
An atheros usb behaves normally. 20dBm max, settable to max of 20.
Internal broadcom works normally. max of 19dBm for 2.4 and 21 for 5ghz, enforced properly.

The only thing the errant cards have in common is that the two n's use RT2800USB. the 036EW (bg) uses RTL8187 though...
2013-03-30
charonsecurity

Did I read this right? You have 5 wireless cards in one system? Aside from the power issue, I'm very curious how you utilize them in conjunction?
2013-03-31
muffinman

The answer is simple:
Some cards are hard set to a certain or max db level and others are not. When you change the reg set to BO, you are forcing the card to run at the 30db level.
If it is hard set to run at 30db and its maximum is 20 then you are likely to damage the card.

In most cases I have found setting the domain to BO does little to nothing. I have a 1000mw AWUS036H and 2000mw AWUS036NH and the 1W gets the same range (give or take 20m) as the 2W at their maximum setting. In fact, the 2W sometimes doesn't pick up the same networks.
I would suggest just running with the AWUS036NH and leaving it at that. If you can't do what you have to do from that distance, then you are probably doing it illegally anyway.
2013-04-01
xsspants

Quote:

Originally Posted by charonsecurity

Did I read this right? You have 5 wireless cards in one system? Aside from the power issue, I'm very curious how you utilize them in conjunction?

Oh, purely for testing. i saw an issue with one and troubleshooted through all wifi cards I own.

After I posted this I tested an Intel 6250 (properly enforced) and an Internal atheros in an Eee (properly enforced).

Quote:

Originally Posted by muffinman

, then you are probably doing it illegally anyway.

I did an authorized pentest from half a mile away just to prove a point once :)

But yeah