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nawitus

Member

Registered: 2009-05-11

Posts: 112

Slow WLAN

Okay, I thought my ADSL modem was crap since I could only download at 6.5Mbps on WLAN, but full 10Mbps on wired, so I bought myself a WLAN router called Belkin N which should be pretty fast. The problem is that using it can I still download at around 6.5Mbps, but when I use wired connection to the Belkin I can downloat at 10Mbps, so the problem might be with my PC / Wlan card. It doesn't support 802.11/n though, but does 802.11/b+g. Here's some info:

nawi ~ $ iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"nawlan"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: 00:22:75:02:DF:B7   
          Bit Rate=54 Mb/s   Tx-Power=27 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=66/70  Signal level=-44 dBm  Noise level=-67 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

    Cell 02 - Address: 00:22:75:02:DF:B7
                    Channel:6
                    Frequency:2.437 GHz (Channel 6)
                    Quality=67/70  Signal level=-43 dBm  
                    Encryption key:on
                    ESSID:"nawlan"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 9 Mb/s
                              18 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 12 Mb/s; 24 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=00000000272a914a
                    Extra: Last beacon: 1510ms ago
                    IE: Unknown: 00066E61776C616E
                    IE: Unknown: 010882848B961224486C
                    IE: Unknown: 030106
                    IE: Unknown: 2A0104
                    IE: Unknown: 32048C98B060
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (2) : TKIP CCMP
                        Authentication Suites (1) : PSK
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (2) : TKIP CCMP
                        Authentication Suites (1) : PSK
                    IE: Unknown: DD07000C4304000000
                    IE: Unknown: 0706555320010B10

Also, how can I check which wlan card driver I'm using? I remember some talk that there were couple of options, one of them having slow speeds, so that might be the issue.

blasse

Member

From: Poland

Registered: 2008-04-24

Posts: 303

Re: Slow WLAN

I could only download at 6.5Mbps on WLAN, but full 10Mbps on wired

You could download with 6,5 megabytes per second or megabits per second? This is common error.
54mbps wifi is 54 megabits per second = 6,75 megabytes per second
LAN should have 100 or 1000 megabits per second = 12,5 or 125 megabytes per second.

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Proud ex-maintainer of firefox-pgo

nawitus

Member

Registered: 2009-05-11

Posts: 112

Re: Slow WLAN

It's megaBITS. The actual speed is around 770kiloBYTES per second (which is 6.1 megabits per second). When wired, I can get 10.9 megaBITS on speedtest.net, and 1.3 megaBYTES =  10.4 megabits per second on regular download. Basically what I'm saying is that the issue is not confusion over bits/bytes.

Here's my card:
03:00.0 Network controller: Broadcom Corporation BCM4312 802.11a/b/g (rev 02)
My modules show this: 'b43 !bcm43xx !ndiswrapper'

nawi ~ $ modinfo b43
filename:       /lib/modules/2.6.31-ARCH/kernel/drivers/net/wireless/b43/b43.ko
firmware:       FW13
license:        GPL
author:         Michael Buesch
author:         Stefano Brivio
author:         Martin Langer
description:    Broadcom B43 wireless driver
alias:          pcmcia:m02D0c0476f*fn*pfn*pa*pb*pc*pd*
alias:          pcmcia:m02D0c0448f*fn*pfn*pa*pb*pc*pd*
alias:          ssb:v4243id0812rev10*
alias:          ssb:v4243id0812rev0F*
alias:          ssb:v4243id0812rev0D*
alias:          ssb:v4243id0812rev0B*
alias:          ssb:v4243id0812rev0A*
alias:          ssb:v4243id0812rev09*
alias:          ssb:v4243id0812rev07*
alias:          ssb:v4243id0812rev06*
alias:          ssb:v4243id0812rev05*
depends:        pcmcia,mac80211,ssb,led-class,cfg80211,pcmcia_core
vermagic:       2.6.31-ARCH SMP preempt mod_unload 686 
parm:           bad_frames_preempt:enable(1) / disable(0) Bad Frames Preemption (int)
parm:           fwpostfix:Postfix for the .fw files to load. (string)
parm:           hwpctl:Enable hardware-side power control (default off) (int)
parm:           nohwcrypt:Disable hardware encryption. (int)
parm:           qos:Enable QOS support (default on) (int)
parm:           btcoex:Enable Bluetooth coexistance (default on) (int)
parm:           verbose:Log message verbosity: 0=error, 1=warn, 2=info(default), 3=debug (int)

Edit: I read that there exists this problem with b43 driver:
*Interference mitigation.
At my apartment I can see like 6-8 other WLAN connections, so maybe this interference causes slow speeds? But that seems weird since the speed is always low, one would assume that it would sometimes peak at high speeds at least.

Also, my kernel is 2.6.31.5-1

Last edited by nawitus (2009-11-06 15:33:14)

blasse

Member

From: Poland

Registered: 2008-04-24

Posts: 303

Re: Slow WLAN

Check wlan channel. The difference between yours and any other should be at least two free channels to achieve maximum speed.

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Proud ex-maintainer of firefox-pgo

nawitus

Member

Registered: 2009-05-11

Posts: 112

Re: Slow WLAN

I was on channel 6. It was used by ~2 other wlan networks. I tried channels 11,12,13 and network manager could not see the network. I then tried channels 9,8,7,5,6 and it tries to connect but does not. I get the connecting icon and 2 green lights. My wlan doesn't work at all anymore.
edit: works after modem and router boot

Last edited by nawitus (2009-11-09 08:42:08)