Re: [ietf-smtp] broken signatures, was Curious

Hector Santos <> Wed, 22 July 2020 01:55 UTC

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Date: Tue, 21 Jul 2020 21:55:08 -0400
From: Hector Santos <>
Organization: Santronics Software, Inc.
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To: Michael Richardson <>, Paul Smith <>
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Subject: Re: [ietf-smtp] broken signatures, was Curious
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On 7/21/2020 6:25 PM, Michael Richardson wrote:

> I suspect that this would at least make a lot of us less grumpy about excess headers.
> I don't subscribe to the idea that the target MTA should rip everything other
> than From/To/Subject/Date out.  That would limit our ability to innovate, and
> there sure has been a lot of that!  But, surely, any system that knows what
> some header is, (such as X-BeenThere or X-GRID-REF) *is* ought to rip that
> out as it knows whether or not its useful.

A MUA does not display all headers. It only extract and displays what 
it needs. For anymore starting to write an MUA from scratch, the 
fields you will need to first deal with for display are 

The OffLine MUA will need all the headers because it handles the 
rendering. The Online MUA will not need all the headers because the 
centralized backend handles the rendering.

Hector Santos,