[KLUG Members] junk mail filters

[Mike Williams]

Jason Edward Durrett wrote:
>
> On  my network I use a combination of grey-listing, dbls, rdns checks, 
> syntax checks, etc during smtp - this is extremely effective at 
> rejecting spam while still notifying a sender in case there is a false 
> positive.  I have been fooling with using spam assassin during smtp 
> but have not put it into production yet (sa-exim) - when I do that 
> should eliminate the small trickle of spam on my network now - about 
> 98% of the connections I get are dropped and an explicit reject is sent.
>
> Before I implemented this I was using filters, mainly on thunderbird 
> on windows machines and mail on os x machines - They became useless 
> because the sales people were getting orders, the orders were going to 
> junk,  the customers were calling weeks later and complaining that 
> they never got their shipment . . . . etc etc.  Everyone had to be 
> reminded to check their junk mail daily - so the spam was actually 
> getting through.
>
> My concern is that as more people use filters as a solution, the more 
> legitimate mail goes to them and the more the IT guys have to walk 
> around the office reminding people to check their junk mail . . .
>
I guess by filter I meant any spam solution, as their purpose is to 
filter out the spam and leave the legitimate email.  Grey-listing, 
blacklists, whatever.  It's a problem that so far seems to be solvable, 
but the way SMTP was designed the deck is heavily stacked in favor of 
spam.  Most spam campaigns only need a 1 in 1000 response rate to be 
economically viable, and unless that changes it's going to continue to 
be a problem.