One consideration is that spam getting through is never more than an
annoyance. Ham getting caught can be a big problem. So any kind of "deny
by default" system has to deal with how to respond to people sending you
mail that gets trapped and provide a way for the sender to "get
approval". How does one join the "global whitelist" and how does one
prevent spammers from joining it?
I dont think spam will ever go away until sending email costs money, via
some kind of global digital stamp system. Which, frankly, i would
welcome with open arms, but will probably never happen.
Dan has a good point; on the surface at least. spam now accounts for
80%+ of all mail, so why are we concentrating on that?
At least the point is worth debate (IMHO).
Can it be done? Even I can see that it can, given the right impetus.
Though perhaps too many companies are making a good $/£/Y off
anti-spam systems based on, around or directly using SA.
Be interesting to see where this thread goes.
Kind regards
Nigel
