[db-wg] Internationalized domain names in the data abase?

In message <DBB71EC8-7564-4AAB-B490-5A894B39AF72 at ripe.net>, 
Edward Shryane <eshryane at ripe.net> wrote:

>> What I found was *not* an internationalized domain name, per se.  Well,
>> maybe it was/is and maybe it wasn't/isn't.  I'll let you all decide,
>> and then you can tell me if I have used improper terminology to
>> descrtbe what I found.
>
>The email address you found, is the only IDN (i.e. non-ASCII) email
>address in the RIPE database (so far).

What I found is definitely *not* "US-ASCII" i.e. 7-but ASCII.  It is
a separate question as to whether or not what I found qualifies,
properly, under the relevant RFCs, as being a proper sort of a
representation of an "IDN".  (I suspect it does not.)

The relevant current RFCs appear to be RFC5890 and possibly RFC5891,
RFC5892, and RFC5894, but I'm sorry to say that each of these is rather
complex, and I do not have time available right now to dredge into
them and learn the real current rules.  All I can say is that a brief
glance at these RFCs seems to indicate that RFC5892 is the most
directly relevant, and that RFC5892 appears to say that Unicode
must be used for representation of IDNs.

The domain name I found *is* ISO-8859-1 (Latin-1) but does not appear
to me to be Unicode.

>It's currently considered a valid value in the RIPE database, as it's
>composed of Latin-1 characters, and the attribute syntax check passes.

Yes.

>There is also an MX record for the domain (although the host
>dc-eb0309b6496a.xn--zrich-kva.email is currently unreachable for me).
>
>However, it may cause inter-operability issues, as the sending mail
>server needs to handle IDN addresses correctly.

Yes.

>DB-WG: should we allow non-ASCII addresses in the RIPE database?

More precisely, the question should be, I think:  (a) Should charcters
that are non-US-ASCII be allowed in the data base generally, and
separately (b) how should IDNs be represented in the data base?

>DB-WG: is punycode for domain names a viable alternative for encoding
>non-ASCII email addresses?

I think that in order to be comprehensive, domain names appearing in the
data base *must* be encoded *either* as punycode *or* else as UTF-8.
I don't believe that ISO-8859-1 (Latin-1) will be able to do the job
entirely, but the other two options will.

>For example, the punycode equivalent abuse at xn--zrich-kva.email is
>already a valid value for the e-mail (or abuse-c) attribute.

Yes, and the same can be said generally. i.e. the (punycoded) domain name
xn--zrich-kva.email is in all respects a substitute for its Unicode
equivalent.  Thus, xn--zrich-kva.email may be used, for example, as
the argument to the "dig" command, and/or in all other contexts where
a fully qualified domain name may be used.

Regards,
rfg