[dns-operations] NXDOMAIN vs NOERROR/no answers for non-existant records

[Dave Lawrence]

Matthew Richardson writes:
> However, is this going to cause any practical problems?

Even outside DNSSEC, where it absolutely would be a problem, there are
some context for specialty applications where the difference between
the two types of negative answers is meaningful.  The examples I can
think of off the top of my head are proprietary, but the general idea
should hold: if two things have semantically different meanings,
people somewhere are making use of the distinction.