After the latest round of spam in my mail box from throwaway accounts
plus
a spate of damn junk faxes.....
Anyone implemented per message limits on SMTP mail?
1) a billing structure that allows say 1000 outgoing mail messages
and either charges or shuts off the account beyond that.
I wrote a series of scripts that injected each syslog mail entry
into a Sybase database in real time at a previous job.
2) filters on dialup accounts that prevent SMTP connections to anything
but the local SMTP server (much as there are spoofing filters
on most dialup routers nowadays)
3) you'd have to authenticate your SMTP connections, which if they're
from your
local dialup pool, should be nothing more than checking your real
time accounting database. (most ISPs aren't running real time
accounting, but probably should be just to prevent multiple account
abuse).
A feature rich Radius server seems to be sorely lacking. This seems to
be one piece of software that many large ISPs are writing on their own.
4) you could always allow "good" customers access through if they really
needed
SMTP access for some reason or another.
The basic idea would be to get rid of the damn $20 dialup accounts
most of the spam that is hitting my mailbox seems to be coming from.
Anyone see any gaping flaws in this logic?
BTW, there is a nanog digest going out twice daily.
I'm willing to add any procmail filters for anything that will increase
signal
to noise.