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vyco10
March 13th, 2009, 01:02 AM
=====
Info
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PC: Dell Latitude 110L
Operating System: Intrepid Ibex (8.10)
Wireless Brand, Model, Chipset: Network controller Broadcom Corporation BCM4318 [AirForce One 54g] 802.11g Wireless LAN Controller
Wireless Driver: b43
Interface check:

Mode:Managed Frequency:2.437 GHz Access Point:
Bit Rate=1 Mb/s Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Power Management:off
Link Quality=71/100 Signal level:-40 dBm Noise level=-71 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

Wireless Router: Linksys WRT54GS V2.0/Firmware: Tomato

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Issue
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As you can see from the output of the iwconfig command, the Link Quality is at 71/100. It is almost always in that range. Considering that I'm no more than five or six feet from my wireless router shouldn't it be at least 95%, if not 100%, consistently?

Is this something that is an issue with the b43 driver and this particular card and not fixable, or is there some configuration change I can make to increase the link quality?

NOTE: Considering that I have the Tomato firmware installed on the Linksys router some may wonder if this is the reason for the degraded link quality, but this has been an issue before and after the Tomato install, which I did just this afternoon. I even boosted the Transmission Power to 84mW thinking that it might help the issue, but it hasn't affected it at all.

Thanks for help anyone can provide.

vyco10
March 13th, 2009, 06:49 PM
Bump

vyco10
March 14th, 2009, 02:31 AM
Bump +2

helgman
March 14th, 2009, 12:28 PM
As you can see from the output of the iwconfig command, the Link Quality is at 71/100. It is almost always in that range. Considering that I'm no more than five or six feet from my wireless router shouldn't it be at least 95%, if not 100%, consistently?

The man page for iwconfig (http://linux.die.net/man/8/iwconfig) says:


Link quality
Overall quality of the link. May be based on the level of contention or interference, the bit or frame error rate, how good the received signal is, some timing synchronisation, or other hardware metric. This is an aggregate value, and depends totally on the driver and hardware.

But I also see that your Bit Rate is 1Mb/s and I'm not sure that's a part of the 802.11G standard or if it's only supported in 802.11B (maybe someone else (Google) knows) - if you are using 802.11G this might be worth investigating. Have you tried with it with some other wireless client? Also, is there any chance of interference from other appliances using the 2.4GHz spectrum?

Guess I'm not helping much ... just bumping the thread for you. ;-)

Regards,
Helgman

vyco10
March 14th, 2009, 05:52 PM
The man page for iwconfig (http://linux.die.net/man/8/iwconfig) says:



But I also see that your Bit Rate is 1Mb/s and I'm not sure that's a part of the 802.11G standard or if it's only supported in 802.11B (maybe someone else (Google) knows) - if you are using 802.11G this might be worth investigating. Have you tried with it with some other wireless client? Also, is there any chance of interference from other appliances using the 2.4GHz spectrum?

Guess I'm not helping much ... just bumping the thread for you. ;-)

Regards,
Helgman

Wanna see something really screwy I didn't see until just now (thanks to your pointing out the MB/s rate)? Here are back-to-back iwconfig commands and their outputs:


wlan0
Mode:Managed Frequency:2.462 GHz Access Point:
Bit Rate=18 Mb/s Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Power Management:off
Link Quality=70/100 Signal level:-42 dBm Noise level=-72 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0


and...


wlan0
Mode:Managed Frequency:2.462 GHz Access Point:
Bit Rate=54 Mb/s Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Power Management:off
Link Quality=70/100 Signal level:-42 dBm Noise level=-72 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0


Oh, and here is yet another instance...



Mode:Managed Frequency:2.462 GHz Access Point:
Bit Rate=1 Mb/s Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Power Management:off
Link Quality=68/100 Signal level:-43 dBm Noise level=-71 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0


Back to 1MB. And yet another...


Mode:Managed Frequency:2.462 GHz Access Point:
Bit Rate=12 Mb/s Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Power Management:off
Link Quality=75/100 Signal level:-37 dBm Noise level=-72 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0


Maybe I'm barking at a reflection of myself in the mirror, this is confusing the crap out of me. http://www.websitetoolbox.com/images/boards/smilies/confused.gif

vyco10
March 19th, 2009, 05:32 PM
Bump