Subject: RE: [idn] some comments about draft-ietf-idn-idna-08.txt

From: "Codogno Maurizio (Rozzano)" <[email-masked]>
Date: Tue, 11 Jun 2002 15:51:16 +0200

Adam:
Well, I hope I did not cause too much of a feud!

Actually I followed closely the first year of activity in the 
group, so at least I had a starting point. Some of the comments
I made tried to be from the side of the casual implementor.

[Sect. 4.1., para 4.]  

IMHO, adding the sentence "ToASCII fails if any step of it fails" 
is enough to clarify the algorithm.

> > Sect 3, req. 2). "An equivalent domain name".  It is a *unique*
> > equivalent domain name, right?
> 
> Not necessarily.  Punycode and ToASCII don't say whether uppercase
> or lowercase ASCII letters will be used in ACE labels. 

oops... I forgot that mixed case may happen. You are quite right,
of course. I only wanted to point out (again, since the concept is
stated elsewhere) that up to upper/lowercase the conversion is unique.

> By the way, an editing error in this paragraph was fixed 
> between idna-08
> and idna-09.

I just found it in the site for the group. Was it already officially
issued?

[ACE labels]
> We make one general recommendation regarding user interfaces: 
> try not to
> show ACE to users unless they ask for it.  I don't think it's 
> our place
> to get into the specifics of how the user asks or how the ACE 
> is shown.

Ok, I think I understand it. My concerns were on the line of 
"if a Unicode character may not be displayed, it could be useful
to show the original string so that the user could notice the 
difference", but you are right: it is an application issue and it
does not belong here.

> > Sect. 8. Why EDNS has not been included in the specifications?
> 
> The whole point of IDNA is that it doesn't depend on any changes to
> the infrastructure, neither the DNS infrastructure nor any other
> infrastructure (like mail relays and web caches).  The STD-13 DNS
> service is entirely sufficient for IDNA; EDNS is not needed.

Of course it is not *needed*, but I was thinking at something a bit
different. EDNS could have been shown as an *example* of a possible
solution to the lengthening of labels, without any endorsing. 

> > As a side issue, I'd like to be pointed at some heuristic 
> data about 
> > Punycode.
> 
> I compared Punycode (back when it was called AMC-ACE-Z) against some
> other algorithms:
> 
> http://www.cs.berkeley.edu/~amc/idn/ace-eval.gz

got it, thanks.

Thank you again, .mau.

---

From: "Adam M. Costello" <[email-masked]>
Date: Tue, 11 Jun 2002 20:13:23 +0000

"Codogno Maurizio (Rozzano)" <[email-masked]> wrote:

> > By the way, an editing error in this paragraph was fixed between
> > idna-08 and idna-09.
>

I think so.

> EDNS could have been shown as an *example* of a possible solution to
> the lengthening of labels, without any endorsing.

If EDNS is used to create labels that are too long for IDNA, then there
will be incompatibility between the old infrastructure and the new
applications.  The issue of how or whether to use EDNS for IDNs is still
too controversial.

AMC