Subject: [dane] Speaking of mailbox names in the DNS

From: "John R Levine" <[email-masked]>
Date: 14 Nov 2015 16:49:08 -0500

Take a look at RFC 6763 on DNS-SD.  Section 4.1.1 says you put the name of 
the service instance directly in the DNS as Net-Unicode which is basically 
UTF-8 minus control characters:

    ...  Because Service Instance
    Names are not host names, they are not constrained by the usual rules
    for host names [RFC1033] [RFC1034] [RFC1035], and rich-text service
    subdomains are allowed and encouraged, for example:

      Building 2, 1st Floor  .  example  .  com  .
      Building 2, 2nd Floor  .  example  .  com  .
      Building 2, 3rd Floor  .  example  .  com  .
      Building 2, 4th Floor  .  example  .  com  .

    In addition, because Service Instance Names are not constrained by
    the limitations of host names, this document recommends that they be
    stored in the DNS, and communicated over the wire, encoded as
    straightforward canonical precomposed UTF-8 [RFC3629] "Net-Unicode"
    (Unicode Normalization Form C) [RFC5198] text.

Since DNS-SD is widely deployed and the world hasn't come to an end, I 
don't see why mailbox names need anything else.  This has the side effect 
of case folding ASCII characters, which some people appear to think is 
important.

R's,
John