Re: [idn] Alternative Solutions

["Edmon" <edmon@neteka.com>]

Extending your idea back to an algorithmic approach, we could set it so that
the LDH names be created using ACE and that nameservers during loading would
check that they are consistent with the unicode name.  When the LDH response
is received by the DNS, it will be utilized for other protocols such as
mail.
Edmon

> Edmon <edmon@neteka.com> wrote:
>
> > Server-side ACE - ACE transformation takes place at server end
>
> If it's on the server, it doesn't have to be an algorithmic
> transformation; it can just be a distributed lookup table (which is what
> DNS is anyway).
>
> Two new resource record types could be created, one that gives the
> Unicode domain name associated with an LDH (letter/digit/hyphen) name,
> and one that gives the LDH name associated with a Unicode name.  This
> is analogous to the A and PTR records that map between LDH names and IP
> addresses in both directions.
>
> Example scenario:  I type a Cyrillic email address into my IDN-aware
> email program.  It performs nameprep and sends the result in a DNS
> query using a canonical encoding (UTF-16 say).  It gets back both an IP
> address (which it uses to connect to the remote SMTP server if there is
> no MX record) and an LDH domain name.  It puts the LDH name in the To:
> field of the message header, in order to conform to RFC 822.
>
> Suppose the message is sent to multiple recipients.  They can all reply
> to everyone in the To: field, because the domain names there are LDH
> names.  Additionally, IDN-aware mail programs can do a DNS lookup on the
> LDH domain names to discover the corresponding Unicode domain names, and
> show the latter to the user.
>
> I don't think this requires any changes to the DNS protocol, only the
> addition of two new resource record types.
>
> I don't like this idea as much as ACE, for two reasons:  First, the
> mapping between LDH names and Unicode names cannot be done offline.
> Second, there is no guarantee that the mapping is consistent in the
> two directions (just as there is currently no guarantee of consistency
> between A and PTR records).  It has one advantage over ACE, though:  The
> LDH names can be chosen arbitrarily, and need not look like gibberish.
>
> AMC