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

John Levine <johnl@taugh.com> Tue, 30 March 2021 22:09 UTC

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From: John Levine <johnl@taugh.com>
To: ietf-smtp@ietf.org
Cc: paul@pscs.co.uk
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Subject: Re: [ietf-smtp] Quoted-Printable-8bit
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It appears that Paul Smith  <paul@pscs.co.uk> said:
>We dont either, but RFC 6152 (written in 2011) has the text that [if the 
>server does not advertise 8BITMIME support]:
>
>    "then the client SMTP must not, under any circumstances, attempt to
>    transfer a content that contains characters outside of the US-ASCII
>    octet range (hex 00-7F)."
>
>This seemed quite a strongly worded requirement, so we'd made the 
>decision that that requirement made it too complicated to handle 
>gracefully, and as it was so strongly worded, we'd better not ignore it.
>
>But, if people are ignoring that requirement, it's actually interesting. 
>Not because people aren't following the standards, but that suggests 
>that 8BITMIME isn't actually that widely used...

I think you're right.  If your user base speaks English, it is not
likely to be sending around a lot of text where 8BITMIME would help,
and binary data is all sent as base64 because as we have seen,
the 25% bloat hasn't been enough to invent something like quoted-unprintable.

For really large stuff, people use Dropbox and its competitors.

R's,
John

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