[ietf-dkim] 1193 considered harmful

[Hector Santos]

----- Original Message -----
From: "Arvel Hathcock" <arvel.hathcock at altn.com>


>> and the question is left at whether same-body/different-header
>> messages are actually sent.  I am saying that they are.
>
> Right, it's very common isn't it?  Doesn't this mailing list do it?

But the irony, DKIM is being supported by the DMA as their ticket to
legitimacy and their wishes can be very costly.  If it wasn't obvious, the
reference is when you have a message body template like so:

   Dear  %FIRST.NAME%

   Do you suffer from %PROBLEM%?   If so, then we have %SOLUTION%
   at a cost of %COST% designed just for you!

Template variables %PROBLEM%, %SOLUTION% and %COST% is common. But
%FIRST.NAME% is not requiring each message to be individualized.

This means if you have 1,000,000 target addresses, you need either:

    1) 1,000,000 individual storage files, or
    2) A smart MTA that performs template macro substitution dynamically
       at the SMTP session.

Most models exist,  DKIM caters to #1.  #2 will require DKIM hashing at the
SMTP stage.

--
Hector Santos, Santronics Software, Inc.
http://www.santronics.com