Re: [idn] Length limits on a domain name

[James Seng <jseng@pobox.org.sg>]

Dan wrote:
> But by only allowing an ACE we are stuck in the ASCII world forever.
> The ACE is for backward compatibility. It is a transition mechanism
> to support old software that cannot handle non-ASCII in domain names.

Agreed.
 
> Should not the requirement on length of IDNs be:
> An IDN may have a maximum of 63 CHARACTERS per label and a total
> length of 255 CHARACTERS?
> 
> A CHARACTER can be defined as the number of UCS-4 characters that is
> used when the name uses when it is in UCS normalised using Unicode
> normalisation form C. This would give the DNS implementors a maximum
> limit to adopt their data structures to. (adding that remaining combining
> characters should not be counted would make it possible to make names taking
> much more space).

I would not go as far as making this a requirement. It is definately nice to
have the ability to have longer domain names (incidently 63 CHAR per label may
not be long enough for some language either), it means a fumanental change in
DNS system, comfirm.

One would wonder with EDNS0 coming in, why not EDNS1 which gives the ability
to have longer domain names...:-) I am dreaming and talking abt things I dont
know.

-James Seng