Using the RASPPPOE driver, you can connect to the net like a dial-up connection. The RASPPPOE s/w installs a dialer, using which you can dial-in and hang-up the connection when you want, unlike the normal PPPOE connection, where you usually would plug-in the router to get connected.
To use RASPPOE, go to your router settings page (type 192.168.1.1 in your browser) and set the connection type to Bridged Mode (1483 IP LLC). Put the username and password in the dialer and dial-in.