On 09/01/2019 06.35, John Levine wrote:
My mail server doesn't support or understand any media types at all.
MIME and media types are all handled in the MUA.
I agree, except for BINARYMIME: the one MIME type advertised in the
greeting stage of ESMTP.
Binary is a content transfer encoding, not a media type.
Does your MTA use a mail store based on mbox files? Many still do;
that means no BINARYMIME.
Not true - transcoding is always a possibility, and transcoding requires
no understanding of specific media types.
This was designed into MIME from the start.
Do you only support DATA for sending mail
bodies (no BDAT); that also means no BINARYMIME.
Again, transcoding address this.
Can you imagine the bandwidth saved (and carbon emissions, storage,
etc.) if we had universal support for BINARYMIME? No more encoding
photos and videos as base64 text.
Transcoding can also be used to upconvert to binary. These days you have to
stay away from transcoding after submission and before final delivery in order
not to break signatures, but nothing prevents it from being used on, say,
But the availability of the technology doesn't mean people will use it. The
asessment of most seems to be that the benefits don't outweigh the costs.
As for text/markdown as a MIME type: it would be nice to have
something lighter than HTML for simple formatted text. But we already
have text/enriched defined in RFC 1896 and that seems to have zero
HTML as a “standard” is a dog's dinner.
Even if it were true, it doesn't make it any less popular.
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