Re: Can we back up a bit and ask some basic questions?An alternate model

----- Original Message -----
From: "Paul Hoffman / IMC" <[email protected]>
To: <[email protected]>
Sent: Thursday, February 20, 2003 6:40 AM
Subject: Re: Can we back up a bit and ask some basicquestions?Analternate
model


>
> At 8:03 PM +0000 2/19/03, Roy Badami wrote:
> >I think the only way this would be viable is if it was mandatory to
> >convert to IMAA-ACE rather than bounce.
>
> So we need two mechanisms instead of one? And the advantage of that is...?
>
> For those of you who didn't follow the IDN WG for the past few years,
> this is highly analogous to the debate that happened there. The whole
> idea of a "transition" sounds great until you realize that the second
> format is going to be with us forever. Given that the transition
> strategy is harder than simply going with IMAA-ACE, there has to be a
> good reason for it.
>
> I don't consider "UTF-8 is good" to be a good enough reason. (And
> before anyone here calls me "anti-UTF-8", please look at the top of
> the first page of the UTF-8 RFC.)
>
> >The point is that it *is* viable to regard IMAA-ACE as a transition
> >strategy to a native UTF-8 format (at least as far as SMTP based mail
> >goes) because we have a robust negotiation mechanism.  In this way,
> >IMAs are different from IDNs.
>
> Right: we were smart enough not to do that in the IDN WG.
>

The process of query and reply of domain names differ from the mechanism
provided by 2821 in that there is an opportunity for the sending MTA to
negotiate the encoding of destination mailbox names with the receiving MTA.
In that sense, 2821 UTF8ADDRESS can exist as a separate proposal to IMAA.

Here is how both can exist: because IMAA-ACE approach implicitly assumes
2821 IMAA-ACE, a sender/receiver MTA can, using smtp extensions, specify
UTF8ADDRESS or IMAAADDRESS, leaving it up to the intermediate MTA to do the
appropriate conversions if necessary. It is assumed that servers advertising
UTF8ADDRESS have the wherewithal to IDNA the RHS for dns resolution.

jeffrey j zahari