When it comes to Linux, most of the software for the commonly used peripherals remain unsupported in Sri Lanka. Sometimes the software can be downloaded from the community forums, though the remaining stuff still, is on your hands. Recently when I switched to Ubuntu 9.04 (Jaunty), completely from Windows XP, I had to replace my Prolink H9601 ADSL USB Modem with a router since SLT(Sri Lanka Telecom) explicitly mentions that the above modem suits for Windows only. There was a program named UbuDSL which works for Prolink modems *sometimes*, on Ubuntu.
Configuring the CT-5624 4 port ADSL Router was a piece of cake though.
. Just open http://192.168.1.1 and enter both username - admin and password - admin.
 Quick Setup will take you to the web page where you will have to input the username and password given by SLT. After this click 'Save & Reboot'; wait for the router to reboot. After rebooting you will mostly be able to connect to the Internet.
The below describes the further configuration, if the above fails. Since the router comes preconfigured for SLT it should work without these though.
. Configuring Computer [From the SLT Router guide - for Windows Operating System]
TCP/IP Properties (You will not need to do this mostly.) .
Use IP address in the range of 192.168.1.2 - 192.168.1.254
Subnet mask 255.255.255.0
Default gateway 192.168.1.1
Preferred DNS Server 18.104.22.168
Alternate DNS Server 22.214.171.124
. Configuring CT-5624
After the initial configuration, as mentioned in , Select WAN under Advanced Setup tab, and Click Edit.
VPI = 8
VCI = 35
Connection Type - PPP over Ethernet (PPPoE)
Encapsulation Mode - LLC / SNAP-BRIDGING
Enter the username and password provided by SLT.
Enable WAN Service
Check the summary and Save if it is correct. Save/Reboot.
Wait for the router to reboot.
This should work by now.. :)
Click the DNS Server option under Advance Setup to set the DNS Server address.