Blocking ports one by one and filling the Internet by application level proxies (SMTP gateways for port 25) is not a road worth travelling.
Pete
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).
ISP's could then, I suppose, limit every user to 5 emails a minute (or any other number).
That combined with domain-keys and sender-ID could make for a much prettier Internet, don't you think?
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?
Gadi.
