Re: [idn] length restrictions on IDN label

[Soobok Lee <lsb@postel.co.kr>]

I  read your previous long answer. Thanks, Adams.
My comments begins...

Adam M. Costello wrote:

> Soobok Lee <lsb@postel.co.kr> wrote:
>
>  
> > If UTF8-encoded, that valid 8bit label will exceed 63 octets limits
> > (up to 168 octets or more)
> >    
> True.
>
>  
> > which is imposed by RFC1035 even upon non-ASCII 8bit labels .
> >    
> Yes, but labels in DNS containing octets >= 128 are not
> internationalized labels, because internationalized labels use only
> octets <= 127 in DNS. 
Really ?   then, please goto to the next comment below and compare your  
claim with IDNA's utf8 position.

Length restriction itself in RFC1035 seems to have nothing to do with
ASCII and non-ASCII distinctions, from the contexts. UDP packets
length limit or practical label needs  consideration seem to be behind that.

> Labels in DNS containing octets >= 128 are
> mysterious creatures that have no standard interpretation as text
> (because ASCII is the only text encoding used by the DNS standard).
>
>  
> > IDNA section 6.3 does not rule out that utf8 encoded labels may be
> > used in DNS wire protocols in the future.
> >    
> In which case the specification of those future wire protocols will need
> to deal with the fact that UTF-8 forms of internationalized labels can
> have more than 63 octets.  (255 is an upper bound, though not the least
> upper bound.)
"UTF-8 forms of internationalized labels"  are not "internationalized 
labels"  ?
if not, we should call them just " strings" as someone said ?  
I can't understand why utf8-form of a label is not a label.

Soobok Lee