problems with invalid crypt

Live forum:


07-11-2008 21:56:08


I'm new to wifi and I'm going batty trying to set up a simple Ad-Hoc link from an embedded PC to my notebook. The embedded PC has a fresh install of Fedora 9 (2.6.25) and a RT2501USB stick, and the notebook has Fedora 9 and a iwp2200 wifi card.

I have succeeded in configuring the devices. Both associate with the same cell, same channel, same key, ad-hoc mode, same speed, and everything else that shows up in iwconfig output. I use manual IP numbers on 192.168.9.xx/24 and shut down the other ethernet (wired) interfaces. The routing tables look good.

Then I try the following (from the embedded PC)

ping -I wlan0 # that's my notebook's IP number

I get no response. After doing this I do a iwconfig on the notebook and notice that the "Invalid Crypt " count has counted up. (No other errors.)

My (newbie) interpretation of this is that the two devices are indeed talking but have a different idea of what kind of encryption and/or which key to use. On the notebook, iwconfig displays the security mode (i.e., encryption) off, open, or restricted. The rt73usb driver, howver, doesn't report the security mode. I've tried various combos, and I can't get ping to work.

Q) Is there a way to get iwconfig (or any other tool) to print out the security mode with the rt73usb driver ?

Q) Is there any reason Ad-Hoc mode shouldn't work if both ends have encryption set to "off" (I know its not a good idea, but just for testing....)

Q) Any known bugs with kernel 2.6.25 and the rt73usb driver ? (When I bought the USB stick from NewEgg, lots of people posted the it worked "out of the box" with Fedora 9....)

Q) Finally, it seems that whichever of the two computers brings up its wifi interface first reports link quality, signal level, noise level, etc. as 0. The other end shows realistic (and very good) numbers. Is that normal ?

The hard part about this is that I'm doing this work at home with no Internet access. Lots of wear and tear on the old thumb drive...

Any help would be very much appreciated.