Re: [ietf-smtp] New Version Notification for draft-crocker-email-deliveredto-00.txt

[Dave Crocker <[e-mail]>]

On 2/14/2021 3:37 PM, Pete Resnick wrote:
> I generally agree with the above stated principle. The thing that seems 
> different here is that 822, 2822, and 5322 all (for better or worse) 
> treated "trace" as a block containing a Return-Path: field followed by 
> one or more Received: fields, and recommended (to only slightly varying 
> degrees) keeping them in that order. This document (among others) 
> changes that.

This prompted my looking over the relevant portion of RFC 5321.

> 4.4.  Trace Information
> 
>    When an SMTP server receives a message for delivery or further
>    processing, it MUST insert trace ("time stamp" or "Received")
>    information at the beginning of the message content, as discussed in
>    Section 4.1.1.4.


I think that calling Delivered-To: a 'trace' header field ties it to 
this model in ways that aren't appropriate. And it isn't the above model 
that should change.

So while Delivered-to: is similar to an SMTP trace field, it isn't 
actually an example of one.  The fact that it is an MDA-generated field 
rather than an MTA-generated one further justifies breaking this linkage.

d/


-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net