Buffalo WLI-UC-AG300N on Ubuntu 12.04.1 LTS

TIPs for configuring Wi-Fi USB adapter "Buffalo WLI-UC-AG300N" on Ubuntu 12.04.1 LTS.  Note that we manually do it without using NetworkManager.

WLI-UC-AG300N uses Ralink "rt28xx" chip [1].  After inserting the adapter then rt2800usb driver is loaded.  According to [2] it seems that we don't blacklist the driver.

$ lsusb |grep BUFFALO
Bus 002 Device 005: ID 0411:012e BUFFALO INC. (formerly MelCo., Inc.) WLI-UC-AG300N Wireless LAN Adapter

$ lsmod |grep rt28
rt2800usb              22773  0
rt2800lib              58967  1 rt2800usb
crc_ccitt              12707  1 rt2800lib
rt2x00usb              20808  1 rt2800usb
rt2x00lib              55326  3 rt2800usb,rt2800lib,rt2x00usb
mac80211              506862  3 rt2800lib,rt2x00usb,rt2x00lib

Expecting that the adapter will be configured as wlan0, add the following lines in /etc/network/interfaces.

auto wlan0
iface wlan0 inet dhcp 
wpa-conf /etc/wpa_supplicant/wli-uc-ag300n.conf

Now generate the file "wli-uc-ag300n.conf", which was referred in the previous step, using the following command.

$ wpa_passphrase [MY_SSID] [MY_PASSWORD] > wli-uc-ag-300n.conf

The conf file will contain the following lines like:

network={
        ssid="MY_SSID"
        #psk="MY_PASSWORD"
        psk=ENCRYPTED_PASSWORD
}

To use WPA2 and WPA-PSK for encryption protocol and key management respectively, add 2 lines to specify them in the conf file and put in /etc/wpa_supplicant.


network={
        ssid="MY_SSID"
        #psk="MY_PASSWORD"
        psk=ENCRYPTED_PASSWORD
        proto=WPA2
        key_mgmt=WPA-PSK
}

Now configure the Wi-Fi adapter and the PC is connected to the wireless network.  The IPv4 address is also obtained using DHCP.

# service networking restart

The iperf result between 2 Wi-Fi nodes connecting to the same AP is as following.  This is not a very good result but acceptable somehow.  The signal quality is not very good, so it reasonable.
 

$ iperf -c 192.168.0.6 -i 1
------------------------------------------------------------
Client connecting to 192.168.0.6, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[  3] local 192.168.0.9 port 43217 connected with 192.168.0.6 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0- 1.0 sec  2.00 MBytes  16.8 Mbits/sec
[  3]  1.0- 2.0 sec  2.25 MBytes  18.9 Mbits/sec
[  3]  2.0- 3.0 sec  2.50 MBytes  21.0 Mbits/sec
[  3]  3.0- 4.0 sec  2.38 MBytes  19.9 Mbits/sec
[  3]  4.0- 5.0 sec  2.12 MBytes  17.8 Mbits/sec
[  3]  5.0- 6.0 sec  2.50 MBytes  21.0 Mbits/sec
[  3]  6.0- 7.0 sec  1.88 MBytes  15.7 Mbits/sec
[  3]  7.0- 8.0 sec  2.62 MBytes  22.0 Mbits/sec
[  3]  8.0- 9.0 sec  2.75 MBytes  23.1 Mbits/sec
[  3]  9.0-10.0 sec  2.00 MBytes  16.8 Mbits/sec
[  3]  0.0-10.1 sec  23.1 MBytes  19.2 Mbits/sec


$ iwconfig wlan0
wlan0     IEEE 802.11abgn  ESSID:"MY_SSID" 
          Mode:Managed  Frequency:2.442 GHz  Access Point: 00:1B:8B:0A:FA:82  
          Bit Rate=180 Mb/s   Tx-Power=20 dBm  
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=38/70  Signal level=-72 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:77  Invalid misc:216   Missed beacon:0

By the way, who else uses Buffalo WLI-UC-AG300N?:p

[1] http://www.wikidevi.com/wiki/Buffalo_WLI-UC-AG300N
[2] http://d.hatena.ne.jp/ohguma/20120222