nIf you query for data does not exist in a zone,
the NXT RR provides
proof of non-existence
nIf after a query the response is:
uNXDOMAIN: One, and maybe many more, NXT RRs indicate that
the name or a wildcard expansion does not
exist
uNOERROR and empty answer section: The NXT TYPE array proves
that the QTYPE did not exist
nNXT records are generated by tools
uYou do not have to generate NXT RRs by hand