Wifi with Broadcom & ndiswrapper randomly fails

Travers · Tux's lil' helper Joined: 09 Oct 2004 Posts: 142

So, I've installed the drivers for a broadcom 4320 via ndiswrapper. I can connect to AP's and everything seems to work fine. Except, the connection to the AP will randomly fail. The driver is still there and working, but it looses the connection somehow. (I'm less than 3 feet away from the AP with my HP zv5000.) A reboot will fix it.

I turned off wep (portscaned my network first to make sure this was a ok idea... lol wep encryption sucks anyway...) and all that jazz. I have the most plain, default setup with a ssid of pickles.

Has anyone experienced a loss of connection at random without the ability to re connect with out a reboot?

swingarm · Posted: Tue Nov 16, 2004 8:08 am Post subject:

Have you tried getting some different Window's drivers? I had a problem where I had 4 different sets of the same Window's drivers but only 2 of them worked.

mrv · Posted: Wed Nov 24, 2004 9:05 pm Post subject:

Hi,

I have a RT2500-based WLAN card (in PCI-bus). Everything works just fine with ndiswrapper if the WEP (128-bit) is off. If the WEP is enabled, the connection breaks almost immediately after "dhcpcd wlan0".

If have tried both Win2k and WinXP drivers, no differences in the behaviour.

Does anyone have a solution (or proper workaround) for this? I'm using version 0.10 of ndiswrapper. I'm living in a city area and really can't run AP with WEP disabled...

-mrv-

Travers · Tux's lil' helper Joined: 09 Oct 2004 Posts: 142

Bad news: ndiswrapper has alot of trouble with WEP. But, don't blame the wonderful developers who brought us ndiswrapper. You should blame the companies who made your wifi card not to FCC requirements so they cannot release specifications or open-source drivers without consequences.

If you're bent on wep, go get a card that is supported by the linux kernel drivers. Sorry, I can't reccommend anything.

One good way would to just enable MAC filtering on your AP so only you can connect but your data would still be up-for-grab. The way someone could get your data would be with a promiscious rfmon wifi card. They could do this with WEP encryption enabled, too. All you have to do is collect enough data, and a program like AirSnort can pull the key out of the packets in about 2 seconds.

I would recommend encrypting all sensitive data before it leaves your computer such as e-mails and credit cards (usually done by default via SSL.) Someone could still do a man-in-the-middle attack, so make sure you inspect SSL and RSA certificates carefully. You could do ethernet but that is vulnerable to man-in-the-middle too. I know a guy who busted a hole in the wall of his dorm, got access to a large sum of ehternet cables, did a few splices, and was reading other people's mail... but that's not really man-in-the-middle. That's just packet sniffing.

But if you do get a new card and do WEP, make sure you go with WPA, which is a automated way to change your WEP key often to avoild WEP key cracking via packet collecting. Even WPA is not secure, since there are techniques to get enough packets before the key changes.

Anyhow, where there is a system, there is a compromise. The easiest way to win is not to play--don't have any data you need to keep safe, and remove that damned sticky note with your passwords from your monitor. =)

mrv · Posted: Thu Nov 25, 2004 9:47 am Post subject:

Hi,

Seems to be working fine now. I found out from some other thread that kernel parameter "acpi=noirq" might help; and it did

Travers, I totally agree with your comments.

-mrv-

Travers · Tux's lil' helper Joined: 09 Oct 2004 Posts: 142

Yes,

cluster one · Posted: Thu Nov 25, 2004 7:21 pm Post subject:

Here's how I added it: