Today I got a chance to test whether we could authenticate PPPoE via Ubuntu. I found that PPPoE configuration to be quite simple via frontend tool pppoeconf. I used to use wvdial command for dial-up configuration.
Provide the information required by the program, it will ask for your username and passsword. So type in your BSNL username, password and click OK. Accept the default values suggested by the program for rest of the settings. You will also be asked to start PPPoeConf connection during the system boot up or you can also do it manually by using pon
command. To connect to internet type the command pon dsl-provider
and to disconnect type in poff
.