Subject: Re: [idn] Let's go forward with IDNA and UTF-8

From: Dan Oscarsson <[email-masked]>
Date: Mon, 28 May 2001 08:06:04 +0200 (MEST)

Mats wrote:
>
>> But ACE+nameprep IS destroying information.
>>
>> Also ACE can only be used for host names, if may not fit all types of
>> DNS names and it cannot be used for other textual data in DNS.
>
>Well, nameprep+UTF-8 will cause the same problem when it comes to the name
>part. There is no difference in what codepoints that ACE can handle
>compared to UTF-8. Nameprep is there to eliminate ambiguity, and will be
>needed for any solution (ACE, UTF-8) to avoide chaos in DNS.

Not if you compare UDNS with IDNA.
In IDNA you do nameprep (and destroy information) in the client.
In UDNS, all UTF-8 encoded data is using normalised UCS form C.
The "nameprep" equivalent is only used in matching of names.
So name can retain all information.

   Dan

---

From: Mats Dufberg <[email-masked]>
Date: Mon, 28 May 2001 09:54:32 +0200 (CEST)

> So name can retain all information.

Still, it has nothing to do with the choice between ACE and UTF-8. The
decision to have nameprep is based on reasoning in a different dimension.
You could have ACE without nameprep.

Mats

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Mats Dufberg                                     +46-8-545 857 06
[email-masked]                           fax: +46-8-545 857 29