ietf-822
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Re: Lessons Learned from a Foreign Culture

1994-10-28 09:20:17
At 10:51 AM 10/28/94, Rick Troth wrote:
       Help me out,  Steve.   I've deleted a bunch of mail,
so I might have missed something.   To transfer agents now act upon the
Content-Type?   The whole reason why MIME was created was  (I thought)
to save ourselves from the evils that the transfer agents might do.

*Someone* must act on the content-type, be it MUA or MTA.

If you have an MTA that accepts RFC 1521 mail on one side and produces
something else on the other, then I think, to work properly, that MTA must
understand MIME content-types.

PMDF is an MTA.  PMDF understands content-types and does the appropriate
transformations (right, Ned?).

       The canonicalization of  CT text/plain  with  CTE Base64
must be handled by the user agent.   The transfer agent is oblivious.

That's one way to do it, yes, and probably the best.  But the MTA can also
unwrap the Base64 and decanonicalize before handing the mail on to the next
step.  Some systems *have* to work that way (eg, gateways into LAN
mailsystems).

CT text/plain  with an absent CTE leaves canonicalization
completely in the hands of the transport agents

Absent CTE == CTE: 7bit; see RFC 1521, page 14, just below the BNF.  Having
CTE missing is not magical.

--
Steve Dorner, Qualcomm Incorporated.  "Oog make mission statement."