I have a small (two on realy) how-to to implement pppoe and radius, the content is in portuguese, you can use google to translate for you. http://www.pruonckk.org/wiki/index.php/PPPoE_Server_with_FreeeRadius http://www.pruonckk.org/wiki/index.php/Mikrotik_with_Radius_for_PPPoE_and_Hotspot