Ted Lemon <ted(_dot_)lemon(_at_)nominum(_dot_)com> wrote:
On external body parts:
Implementing this 20-year-old MIME mechanism would be very difficult,
would have limited potential payoff, and would be pretty obviously
privacy-violating. And in order for it to do any good, recipients would
have to refuse large attachments.
In practice message size limits are typically a few dozen MB, and people
hit this frequently enough for it to be annoying. They also have problems
with security restrictions on attachment file types.
So a number of sites have implemented systems which strip large
attachments, put them on a web server, and modify the message to include a
link to the detached file.
https://fileexchange.imperial.ac.uk/
http://fluff.bris.ac.uk/fluff/
https://webdropoff.auckland.ac.nz/
http://turin.nss.udel.edu/wiki/dropbox/doku.php
etc.
BUT! These systems do not use the MIME external body mechanism, because it
is common for mail servers to reject these messages on the grounds that
they are too difficult to properly scan for viruses.
The end result is something pretty simiilar to MIME external bodies, but
a complete mess from the protocol architecture point of view.
Tony.
--
f.anthony.n.finch <dot(_at_)dotat(_dot_)at> http://dotat.at/
Lundy, Fastnet: Variable, becoming north, 3 or 4. Slight or moderate. Fair.
Good, occasionally moderate.