What is LDNS?

[freebsd at fongaboo.com]

Is LDNS an alternative *authoritative* name server? If so, any good 
tutorials out there?


  -------------------------------------------------------------------------
  shot through the heart              ooh baby do you know what that's worth
  and you're to blame                         ooh heaven is a place on earth
  darling you give love                  they say in heaven love comes first
  a bad name                              we'll make heaven a place on earth
  ORBITAL                                                     "Halcyon Live"