Re: List of ESMTP extensions

[Dan Wing <[e-mail]>]

>> We will likely drop the proposal anyways in favor of 
>> draft-ietf-fax-mdn-features-01.txt, anyways, but if you're honestly
>> interested in a justification for draft-ietf-fax-smtp-capabilities I 
>> can give you several.
>
>Yes, I have a morbid interest in the sources of engineering disasters.

The primary reason to do this is to send color faxes and superfine
faxes, without wasting network bandwidth and without requiring the fax
offramp to downgrade color/superfine faxes if that is necessary
because it connects to a recipient fax machine that doesn't support
color/superfine.

To do this we need to know the capabilities of the recipient.  We're 
already using SMTP, so using SMTP to determine the capabilities of
the recipient seemed like a good idea and avoids the problems of 
out-of-sync caches and the like.

Adding the SMTP extension to an offramp is trivial and solves the 
problem in a way that is analogous to how today's fax machines 
determine recipient capabilities exchange.

As I said, though, we're probably going to let this I-D expire so 
going into a lengthy debate isn't useful.

-Dan Wing