On Sat, 9 Oct 2004, Gadi Evron wrote:
Blocking port 25 for dynamic ranges means they can't send email, so that drone are pretty useless for spammers on that account. Trojan horses would have to use local information for the user's own account (from Outlook or such).
my users like being able to send email. i dont think this can work! (and there are many legit reasons for not using our own smtp servers.. indeed we have custs on other ISPs network who use our smtp server)
ISP's could then, I suppose, limit every user to 5 emails a minute (or any other number).
5 emails or 5 recipients? i can send one email with hundreds/thousands of rcpts.. and again, there are lots of legit reasons for sending a batch of emails
That combined with domain-keys and sender-ID could make for a much prettier Internet, don't you think?
you mean SPF? i agree, use as many tools as are available in conjunction with something like spamassassin to score mails as likely spam
Abuse using port 25 is a major issue today, why not solve it? If a user wants it open, they could always ask for it or even pay more money. Perhaps move to a static IP?
there are many ways of sending spam that dont use port 25.. individual rules are costly to implement and users wont use a service where you have to pay more for basic services Steve