Re: [idn] WG last call documents

["D. J. Bernstein" <djb@cr.yp.to>]

Adam M. Costello writes:
> The existing DNS requires *all* domain labels to be case-insensitive,
> not just host labels.  See RFC 1035.  So domain names are already
> inappropriate for any data types that are case-sensitive.

False. Let's look at what the specifications actually say:

   * RFC 1034 says that ``all present domain functions'' are
     case-insensitive ``assuming an ASCII character set.'' (For
     non-English speakers: ``present'' means ``now existing.'')

   * RFC 1035 says that case-insensitivity is used throughout the domain
     system ``at present.'' (``At present'' means ``at this time.'')

   * RFC 1035, section 2.3.3, quite explicitly allows administrators to
     store case-sensitive data in the domain name system, contrary to
     your claims. Have you ever read the RFC?

Both documents demand that case be preserved. Consequently, if you
destroy the case of (for example) a mailbox name inside an SOA record,
you are violating the DNS specifications.

---D. J. Bernstein, Associate Professor, Department of Mathematics,
Statistics, and Computer Science, University of Illinois at Chicago