On Friday 06 September 2002 20:48, Skip Montanaro wrote:
>     Greg> In case it wasn't obvious, I'm a strong proponent of
> filtering Greg> junk mail as early as possible, ie. right after the
> SMTP DATA Greg> command has been completed.  Filtering spam at the
> MUA just seems Greg> stupid to me -- by the time it gets to me MUA,
> the spammer has Greg> already stolen my bandwidth.
>
> The two problems I see with filtering that early are:
>
>     1. Everyone receiving email via that server will contribute ham
> to the stew, making the Bayesian classification less effective.
>
>     2. Given that there will be some false positives, you absolutely
> have to put the mail somewhere.  You can't simply delete it.  (I also
> don't like the TMDA-ish business of replying with a msg that says,
> "here's what you do to really get your message to me."  That puts an
> extra burden on my correspondents.)  As an individual, I would prefer
> you put spammish messages somewhere where I can review them, not an
> anonymous sysadmin who I might not trust with my personal email
> (nothing against you Greg ;-).
>
> I personally prefer to manage this stuff at the user agent level.
> Bandwidth is a heck of a lot cheaper than my time.
>
I see no reason why both approaches could and should not be used.
MTA level filtering would just need to use a different corpus, one that
would contain illegal or otherwise commonly unapproved material for the
group of people using that MTA.   I'm sure that such an approach would
significantly reduce the mail traffic as a first step, without  giving
false positives.
MUA corpus would then be personally trained -- although I'd like the
option of 'down-loadable' corpuses and merge functionality.
Harri
PS.  Just joined the list, so pardon if my thoughts have been hashed
through before.

[Guido]
> ...
> - A program that acts both as a pop client and a pop server.  You
>   configure it by telling it about your real pop servers.  You then
>   point your mail reader to the pop server at localhost.  When it
>   receives a connection, it connects to the remote pop servers, reads
>   your mail, and gives you only the non-spam.
FYI, I'll never trust such a scheme:  I have no tolerance for false
positives, and indeed do nothing to try to block spam on any of my email
accounts now for that reason.  Deliver all suspected spam to a Spam folder
instead and I'd love it.