Wireless woes
 

I had a strange thing happen to me. I finally had my wireless AP working with my orinoco wireless card. Everything was fine until later on my my connection went dead. My access point is a foot away from my laptop and yet I have zero signal. When I do iwconfig, the essid no longer appears and the mac address of the ap is 44:44:44:44:44:44. I am using mandrake and the wireless card is a pcmcia card.

got double-posted, apologies..

That is indeed strange, were there any intervening events between the "working fine" and the dead connection? perhaps the computer went into standby or suspend? If so, like me you may have to modify your apm scripts, depending on which distro this happened to you would need different modifications, start by looking in /etc/sysconfig/apm-scripts on either redhat or mandrake, additonally you may also find an /etc/sysconfig/apmd on mandrake, I've had to modify these for both redhat 9 and mandrake 9 to get a return from suspend to bring my wireless card back up. This is assuming your box is using apm for power management and not acpi, if you're not using apm, acpi is a deep enough topic that thorough research on your own will be required.

well, i figured out why it was dead. it seems that when i try to use encryption keys or allow only the mac address of mt wireless card, i get no signal. i don't know why it does this. so what i have to do is bring up my wired ethernet and login to my access point and set the factory defaults back to normal. that means that i have a public access point. i have no idea how to get any security and be able to use the access point without my connection going dead.

Try using only 64bit *hex* encryption keys, I too have had some problems going higher, and the time to break the larger keys is not enough different as to make them worth the overhead. To test this, enter the key as root at a console like this: iwconfig devicename key xxxx-xxxx-xx, where devicename is something like eth0, eth1, or wlan0 and the x's are digits 0-9 and/or A-F, unlike most of the rest of linux, case does not matter in this case. The other thing I've seen is that sometimes when people go to secure their wireless network, they (correctly) want to turn off essid broadcasting, this has broken some of my wireless cards in linux and I've had to turn it back on.

As for the MAC address filtering issue, I believe you need to take another look; in the end it's the MAC address that actually becomes an ethernet device's address on a network, not the ip address. So, if any packets have ever been sent to or received from the device under linux, then linux is reporting the MAC correctly, I use MAC filtering with cards from 5 different manufacturers on my router and never a problem with that part of things. I suggest double-checking your router settings, some routers have 2 MAC lists, one for *allow* and for some silly reason, one for *deny*, as if there were only 32 MAC addresses in the world that you want to deny access, but no more. My SMC 2404wbr had *only* the deny list until I upgraded the firmware (also something you may want to look into), look at the setup screens for your router carefully, it's easy to miss this since it doesn't make any sense.

The keys I was using were 64-bit. I am kind of scared to fool around with it right now because everything is finally working as it should. Here's another question, it seems that iptables disrupts a lot of wireless transmissions, does iptables interrupt wirelss transmissions?

Not really... tables can of course monkey with the ethernet layer, but the frame association of the wireless devices is all up in the air.

What firmware are you running?

Its at the end of "dmesg" around the card load, for instance:

There's 8.10, some of the 7's are buggy with orinoco driver versions around .11b, which is what Mandrake shipped with. Its on the mailing list a lot...

Cheers,

Finegan

thanks, I will just keep on playing. Another question for you, do you know anything about changing the txpower on my card. I try iwconfig eth1 txxpower 0 and it says unrecognized command. The current txpower on my card is 15dBm. I have a prism2 chipset and I am not 100 percent sure if that feature is available on my card.

I get:

For me, that's just not in the card, but this is an old orinoco silver. What I remember from the OpenBSD drivers, which say what's available for what card, I think this only worked for Symbol cards what have the hardware to support it. Its not part of the spec... so every card is going to vary in this regard. Offhand, if you're just trying to pump range, setting the "sens" higher will do that, with an increase in latency and a drop in rate of course.

Cheers,

Finegan

My sensitivity right now is 1/3, what would maybe help out my performance for now?

Cranking the sensitivity up is just going to increase overall range, although the usual jumble of a 2.4Ghz cordless phone, the microwave, etc... are going to hose the signal much more often:

iwconfig eth0 sens 3

Should almost double the range for the card, get you a signal through walls, etc... but its probably going to be a 200K/s, which is still faster then say... the DSL into the house which most likely only comes it at 160K/s (using real terminology of Kilobyte instead of kilobit) anyway, but machine to machine transfer is going to be dog slow. Leave the rate set to auto and see what it ramps down to.

Cheers,

Finegan