Re: [ietf-smtp] Quoted-Printable-8bit

Sam Varshavchik <mrsam@courier-mta.com> Tue, 30 March 2021 12:22 UTC

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From: Sam Varshavchik <mrsam@courier-mta.com>
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Date: Tue, 30 Mar 2021 08:22:15 -0400
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Subject: Re: [ietf-smtp] Quoted-Printable-8bit
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Jeremy Harris writes:

> On 30/03/2021 09:52, Paul Smith wrote:
>> On 30/03/2021 02:12, Gene Hightower wrote:
>>> I think the practical answer is that most email is transferred over
>>> TCP these days which is a stream of 8-bit bytes. You sort of get
>>> 8-bits for free without doing anything special. You have to work at
>>> *not* supporting 8BITMIME. So the bar for this feature was very low.
>>
>> So, what do you do if you have an 8-bit message and try to send it to a  
>> server which doesn't support 8BITMIME?
>
> https://cr.yp.to/smtp/8bitmime.html
>
> Summary: 8BITMIME has been irrelevant for years.
> You send it.

Dan Bernstein wrote that as an explanation of why he didn't implement  
8BITMIME in Qmail. But I don't think this was the real reason. It was really  
the same reason as to why Qmail also didn't implement TLS (OpenSSL was  
already in use back then), and also why Qmail used one connection per Email  
when sending mail, look up the MX, connect, send email, disconnect; and  
reconnect again, for another email to the same domain; even when the same  
message had multiple recipients in the same domain, Qmail would still use  
connection per recipient, per email, to the same domain.

It's really the same reason for all of this, as well as 8BITMIME, and that  
documentation was merely his explanation for the 8BITMIME part of that.