Re: [idn] WG last call documents

["Adam M. Costello" <idn.amc+0@nicemice.net.RemoveThisWord>]

"Eric A. Hall" <ehall@ehsco.com> wrote:

> The problem with the current spec is that case-folding and
> normalization will impose restrictions on these assignments.  This
> is inappropriate for a generic i18n domain name label syntax.  On a
> secondary note, normalization and lowercasing are problems having to
> do with hostnames

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.

> > The prohibited list in nameprep is pretty small, and they're all
> > characters that you'd have to be somewhat crazy to want to use in
> > domain names.
> 
> I think you meant hostname here.  Remember that hostname rules apply to
> delegations.  Domain name rules are a broader category which also include
> things like SRV, email addresses, and so forth.

I understand that not all domain names are host names.  I meant domain
names.  Have you actually looked at the prohibited list in Nameprep?  I
think it will be extremely rare that someone wishes they could use one
of those characters in a domain name (of any type).

> The email people will come up with their own character restrictions,
> which is exactly the point.  The namespace should ALLOW them to come
> up with mapping rules, case-folding, normalization and whatever other
> rules they wish.  I mean, if they want to have a perverse mailbox
> sequence, why shouldn't they?  The codecs should only deal with inputs
> and outputs.  I'm pretty certain that's what you were told.

I was basically told not to discuss email local-parts on this mailing
list.

AMC