youtube link for dns tut
http://www.youtube.com/watch?v=r8d-Sv20WCQ
http://www.youtube.com/watch?v=CBJaIahhH20 
http://www.youtube.com/watch?v=wwS6Jufjqds
http://www.youtube.com/watch?v=CBJaIahhH20
http://www.youtube.com/watch?v=wwS6Jufjqds