# iwlagn wireless driver: slow connection on 802.11b [SOLVED]

## Tazmanian

I'm getting very bad network performance with my Intel 4965 AGN wireless adapter.  According to speedtest.net, I'm getting download speeds of ~550 kbit/s, while I see ~4200 kbit/s on another laptop (also running Gentoo) on the same network, sitting right beside this one.  Does anyone know what's going on?

Here are some details.

Lenovo X300 laptop

802.11b network with 128-bit WEP

lspci: Intel Corporation PRO/Wireless 4965 AG or AGN Network Connection (rev 61)

lsmod: iwlagn, iwlcore, mac80211

gentoo-sources-2.6.27-r8

iwl4965-ucode-228.57.2.21

```
# iwconfig wlan0

wlan0     IEEE 802.11abgn  ESSID:"..."  

          Mode:Managed  Frequency:2.462 GHz  Access Point: ...   

          Bit Rate=11 Mb/s   Tx-Power=14 dBm   

          Retry limit:7   RTS thr:off   Fragment thr=2352 B   

          Encryption key:...   Security mode:open

          Power Management:off

          Link Quality=87/100  Signal level:-57 dBm  Noise level=-92 dBm

          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0

          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

```

```
 .config - Linux Kernel v2.6.27-gentoo-r8 Configuration                         

 ────────────────────────────────────────────────────────────────────────────── 

  ┌───────────────────────────── Wireless LAN ──────────────────────────────┐   

  │  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │   

  │  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │   

  │  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │   

  │  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │   

  │ ┌─────────────────────────────────────────────────────────────────────┐ │   

  │ │    [ ] Wireless LAN (pre-802.11)                                    │ │   

  │ │    [*] Wireless LAN (IEEE 802.11)                                   │ │   

  │ │    < >   Intel PRO/Wireless 2100 Network Connection                 │ │   

  │ │    < >   Intel PRO/Wireless 2200BG and 2915ABG Network Connection   │ │   

  │ │    < >   Marvell 8xxx Libertas WLAN driver support                  │ │   

  │ │    < >   Cisco/Aironet 34X/35X/4500/4800 ISA and PCI cards          │ │   

  │ │    < >   Hermes chipset 802.11b support (Orinoco/Prism2/Symbol)     │ │   

  │ │    < >   Atmel at76c50x chipset  802.11b support                    │ │   

  │ │    < >   Intersil Prism GT/Duette/Indigo PCI/Cardbus                │ │   

  │ │    < >   USB ZD1201 based Wireless device support                   │ │   

  │ │    < >   Wireless RNDIS USB support                                 │ │   

  │ │    < >   Realtek 8180/8185 PCI support                              │ │   

  │ │    < >   Realtek 8187 and 8187B USB support                         │ │   

  │ │    < >   ADMtek ADM8211 support                                     │ │   

  │ │    < >   Simulated radio testing tool for mac80211                  │ │   

  │ │    < >   Softmac Prism54 support                                    │ │   

  │ │    < >   Atheros 5xxx wireless cards support                        │ │   

  │ │    < >   Atheros 802.11n wireless cards support                     │ │   

  │ │    -M- Intel Wireless Wifi Core                                     │ │   

  │ │    [*] Iwlwifi RF kill support                                      │ │   

  │ │    [ ] Enable full debugging output in iwlagn driver                │ │   

  │ │    <M> Intel Wireless WiFi Next Gen AGN                             │ │   

  │ │    [*]   Enable Spectrum Measurement in iwlagn driver               │ │   

  │ │    [*]   Enable LEDS features in iwlagn driver                      │ │   

  │ │    [*]   Intel Wireless WiFi 4965AGN                                │ │   

  │ │    [ ]   Intel Wireless WiFi 5000AGN                                │ │   

  │ │    < > Intel PRO/Wireless 3945ABG/BG Network Connection             │ │   

  │ │    < > IEEE 802.11 for Host AP (Prism2/2.5/3 and WEP/TKIP/CCMP)     │ │   

  │ │    < > Broadcom 43xx wireless support (mac80211 stack)              │ │   

  │ │    < > Broadcom 43xx-legacy wireless support (mac80211 stack)       │ │   

  │ │    < > ZyDAS ZD1211/ZD1211B USB-wireless support                    │ │   

  │ │    < > Ralink driver support                                        │ │   

  │ │                                                                     │ │   

  │ │                                                                     │ │   

  │ │                                                                     │ │   

  │ │                                                                     │ │   

  │ └─────────────────────────────────────────────────────────────────────┘ │   

  ├─────────────────────────────────────────────────────────────────────────┤   

  │                    <Select>    < Exit >    < Help >                     │   

  └─────────────────────────────────────────────────────────────────────────┘   

```

Last edited by Tazmanian on Sat Mar 21, 2009 7:19 pm; edited 1 time in total

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## mamac

Hi,

Are the others also on 11 Mb/s ?

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## d2_racing

In fact, your AP seems to be stuck at 11 MB.

Also, what happen when you download something and you run this :

```

# dmesg | grep -i iwl

```

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## Tazmanian

Hi, thanks for your responses.

The AP is running 802.11b, so 11 Mb/s is the most anyone will ever get on this network.  For sanity, here's what I have on the other laptop, which has an "Atheros Communications Inc. AR5212 802.11abg NIC (rev 01)":

```
# iwconfig ath0

ath0      IEEE 802.11b  ESSID:"..."  Nickname:""

          Mode:Managed  Frequency:2.462 GHz  Access Point: ...

          Bit Rate:11 Mb/s   Tx-Power:17 dBm   Sensitivity=1/1

          Retry:off   RTS thr:off   Fragment thr:off

          Encryption key:...   Security mode:restricted

          Power Management:off

          Link Quality=26/70  Signal level=-71 dBm  Noise level=-97 dBm

          Rx invalid nwid:1503741  Rx invalid crypt:0  Rx invalid frag:0

          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
```

Going back to the laptop with the Intel card, here is what I get in dmesg before downloading a 2 MB file.  No new related messages appear during the download.

```
$ dmesg|egrep '(iwl|wlan)'

iwlagn: Intel(R) Wireless WiFi Link AGN driver for Linux, 1.3.27ks

iwlagn: Copyright(c) 2003-2008 Intel Corporation

iwlagn 0000:03:00.0: PCI INT A -> GSI 17 (level, low) -> IRQ 17

iwlagn 0000:03:00.0: setting latency timer to 64

iwlagn: Detected Intel Wireless WiFi Link 4965AGN REV=0x4

iwlagn: Tunable channels: 11 802.11bg, 13 802.11a channels

iwlagn 0000:03:00.0: PCI INT A disabled

phy0: Selected rate control algorithm 'iwl-agn-rs'

iwlagn 0000:03:00.0: PCI INT A -> GSI 17 (level, low) -> IRQ 17

iwlagn 0000:03:00.0: restoring config space at offset 0x1 (was 0x40100102, writing 0x40100106)

firmware: requesting iwlwifi-4965-2.ucode

Registered led device: iwl-phy0:radio

Registered led device: iwl-phy0:assoc

Registered led device: iwl-phy0:RX

Registered led device: iwl-phy0:TX

wlan0: authenticate with AP [mac]

wlan0: authenticated

wlan0: associate with AP [mac]

wlan0: RX AssocResp from [mac] (capab=0x15 status=0 aid=14)

wlan0: associated
```

----------

## Tazmanian

I've solved the problem.  It looks like people on other distros have also been experiencing problems with network throughput on 802.11b networks with the iwlagn driver.  Downloading and installing the latest iwlagn drivers from http://linuxwireless.org/en/users/Download fixes the problem.

Thanks!

----------

## d2_racing

Nice  :Razz: 

----------

