USB ADSL Modems

        Often parts of ADSL USB modem drivers are proprietary, closed source software and so cannot be supplied with Ubuntu. To get a modem to work with these drivers, you will need to download files from Internet with a computer having a working connection, then transfer the downloaded files to you Ubuntu installation.
If you have a modem that can connect both via USB and ethernet, or an ethernet router, you should use the ethernet connection.
USB modem installation will require Internet access to download the necessary proprietary drivers. Configuration is beyond the scope of this guide; please see the links to the relevant installation instructions on the Ubuntu community help site, below.
To identify model of your modem, note the name and number on the front. You may have to look for a label to discover the exact model. Consult the list below to see which driver your modem requires, and note the link.
When you go online to download the necessary drivers, you can download the relevant drivers using the links provided.

1. Speedtouch modems:
   https://help.ubuntu.com/community/UsbAdslModem/SpeedTouch
   
2. Modems using the Analog Devices Inc. eagle-usb I, II or III chipset (such as Sagem Fast 800, Comtrend ct 350 etc.):
   https://help.ubuntu.com/community/UsbAdslModem/ueagle-atm
   https://help.ubuntu.com/community/UsbAdslModem/EagleUsb
   
3. Connexant AccessRunner based modems:
   https://help.ubuntu.com/community/UsbAdslModem/EciAdsl
   https://help.ubuntu.com/community/UsbAdslModem/AccessRunner
   https://help.ubuntu.com/community/UsbAdslModem/e-techV2
   

 https://help.ubuntu.com/8.04/internet/C/modems-adsl-usb.html