On Sat, Sep 12, 2015 at 08:18:49AM +1000, Mark Andrews wrote:
And the DNS is supposed to preserve the case of entered labels.
Later versions of BIND 9 do that to the RRset level and it would
be possible to do it to the RR level if needed.
I am not confident that doing it to the RR level would be a good idea
in the DNS, and I'm not sure that the DNS protocol is sufficiently
carefully described that making the distinction between RRs and the
RRset in this way would be successfully interoperable. Certainly,
this is an area that's underspecified, so there's no way anyone should
be building hopes (never mind a protocol) on top of distinctions
between the RRset's and constituent RR's owner names.
possible to distingish between JoeSmith and joesmith if preservation
to the RR level is done for arbitary DNS data.
But we know perfectly well that the "case preserving but
case-independent matching" has been interpreted in all sorts of
different ways (some obviously wrong, but others different yet
consistent with the RFCs). So let's again please not depend on
anything like this as part of any specification.