Steve, you're authorized if you say you are and agree to accept responsibility. Most corporations would readily provide the addresses of their mail servers; anyone on DSL or cable connection could do the same. But by changing the default behavior to block port 25 until requested, you could readily address the spam problem. It would take some work on the part of operator community (hence the subject), and doesn't fit in the world wide commune perspective of networking, but it would make the Internet far more useful for everyone.
(I realize I'm a few days late on this, been travelling all week) What about that small business with a remote site on a cable modem? All they want is their local server to talk to the one upstream, and they'd rather pay, say, Time Warner $50 a month on a dynamic instead of $200 for a single static IP. Can't really blame them, can you? Is this authorization-filter-scheme going to account for servers on dynamic IP? Rob Nelson ronelson@vt.edu