Re: dropped received packet with no ToDS flag?

From: Jouni Malinen (
Date: 2002-04-04 06:58:53 UTC

On Wed, Apr 03, 2002 at 11:33:57AM -0800, Adam Megacz wrote:

> It takes a really, really long time for clients to associate to the
> AP, and sometimes they fail to do so altogether (ie association time
> exceeds client's timeout value). This happens with Powerbook G4
> clients (internal card, I think it's a Lucent) and my Thinkpad
> (DLINK DWL-500) as well.

Hmm.. Are you using power saving on the client WLAN cards? If yes, please test this without any power saving. There were some problems with acknowledging nullfunc frames (firmware did not do it) for which I had to make a workaround to get Lucent cards associating properly (they were expecting to get the ACK). Something similar might still cause problems.

> Also, about every 10 minutes or so the client will disassociate and
> reassociate to the AP. Since reassociation is flaky, this means that
> about every 10 minutes you have a 20% chance of falling off the
> network. Not good =)

Well, okay, this does not sound very nice.. I would like to get a packet dump from some of these associations for analysis. Could you record this, e.g., by running 3rd host in monitor mode (iwpriv wlan0 monitor 1; wlansniff)?

> Hrm, could you make a snapshot available? I'll try it out and see if
> it solves my problem. I'll also try my DWL-500 in the
> DWL-650... perhaps it's just my lame Addtron card that's causing
> problems.

I added some more debugging info to the driver and I'll send you a snapshot in another message.

> Also, could you tell me what brand PCMCIA card and PCI adapter you're
> using as the author of this driver? I figure buying the same hardware
> that you're using will give me the highest probability of success.

Well.. I'm using quite many different cards and station f/w versions to test the driver. Since all the Prism2 cards I have available seem to be working without much problems, I have assumed that others would work, too (or then I just happen to have good luck in getting all the working models, but none of the incompatible ;-). Anyway, I'm mostly using Compaq WL100, WL200, and D-Link DWL-650 during development.

Compaq WL200 includes Cirrus Logic CL 6729 PCI adapter. In addition to that, I use Ricoh RL5c476 II CardBus bridge (PCI adapter) and Texas Instruments PCI1420 (integrated in a laptop). However, apart from the laptop, these have been quite problematic to setup.. Both Compaq WL200 and Ricoh require external pcmcia-cs (i.e., no kernel tree PCMCIA support) and naturally both resulted in system crashes before proper arguments for kernel and pcmcia-cs were found.. In addition, these cards did not work at all with many of the main boards I first tested..

Jouni Malinen                                            PGP id EFC895FA

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