Re: [idn] length restrictions on IDN label

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

Soobok Lee <lsb@postel.co.kr> wrote:

> > Yes, but labels in DNS containing octets >= 128 are not
> > internationalized labels, because internationalized labels use only
> > octets <= 127 in DNS.
>
> Really ?

Really.

> "UTF-8 forms of internationalized labels" are not "internationalized
> labels" ?

The UTF-8 form of an internationalized label is an internationalized
label.  But that's irrelevant, because labels in DNS containing octets
>= 128 are not UTF-8.  The only text encoding used by DNS is ASCII
(according to the current DNS standard).  The octets >= 128 in DNS are
non-ASCII, but that doesn't mean they are UTF-8.  We don't know what
they are, except octets.

The UTF-8 form of an internationalized label is an internationalized
label, but a sequence of octets with no charset tag is not an
internationalized label (it's not even text).

So I stand by my position quoted at the top of this message.

AMC