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

[Paul Hoffman / IMC <phoffman@xxxxxxx>]

At 7:53 PM +0100 2/24/03, Simon Josefsson wrote:
>  > What is the actual deployment advantage of a ESMTP extension over just
> >  plain IMAA-ACE?
>
> It makes SMTP support non-ASCII for email addresses.  Compared to
> using IMAA-ACE, the advantage is that an ESMTP extension doesn't
> require the use of a punycode encoder/decoder.

Are you saying that using a punycode decoder when writing to a 
message store is *harder* than doing an ESMTP extension that might 
involve bouncing or dropping mail? That seems kind of extreme, given 
that the punycode decoding is completely optional. And I don't 
understand why you talk about a punycode encoder; that is never 
needed by the SMTP server in IMAA-ACE.

>   What would the actual
> deployment advantage of using IMAA-ACE over an ESMTP extension with an
> ACE fallback be?

That there would be no required change to the deployed base of SMTP 
servers out there, some of which are in hardware and cannot be 
upgraded. Internet mail is already deployed; forcing a change when it 
isn't needed is just plain bad design. Localizing the protocol change 
to one place makes it easier to deploy and makes it more predicable 
for end users.

Do I need to go on?

> If you want to deploy as fast as possible and only require changes in
> transport end points, yes.  If you want to upgrade to a clean and
> easily maintined design in the long-term, no.

In what way is using a new ESMTP extension more "easily maintained"? 
That certainly is not the experience in the SMTP world so far.

Clean is in the eye of the beholder. You and I like UTF-8, but many 
people don't. Forcing them to use our preferred charset isn't a good 
practice if it can be avoided.

--Paul Hoffman, Director
--Internet Mail Consortium