Subject: [idn] Forbidden characters

From: Dan Oscarsson <[email-masked]>
Date: Wed, 25 Jul 2001 10:45:59 +0200 (MEST)

If we define that nameprep must be done before names are sent over the
DNS protocol we get a lot of characters that are forbidden in host names.

For example: all upper case letters, double width and circled letters.

This is quite a change from current usage where both upper and lower case
is allowed in host names.

   Dan

---

From: Yves Arrouye <[email-masked]>
Date: Wed, 25 Jul 2001 10:34:27 -0700

> If we define that nameprep must be done before names are sent 
> over the DNS protocol we get a lot of characters that are 
> forbidden in host names.
> 
> This is quite a change from current usage where both upper 
> and lower case is allowed in host names.

They are not forbidden: they will get folded to something else. So you can
still write and register your names with, say, U+00DC LATIN CAPITAL LETTER U
WITH DIAERESIS and U+2462 CIRCLED DIGIT THREE. They can be used in your
applications and by your users. They are just strictly euqivalent to U+00FC
LATIN SAMLL LETTER U WITH DIAERESIS and U+0031 DIGIT ONE. Just like 'A' and
'a' are strictly equivalent today in DNS.

YA