On Tue, 8 Dec 2009, Suresh Ramasubramanian wrote: > > As for a university smarthost getting blocked you'd probably need to > look at one of two things -
Three :-) > 1. Forwarding users on your campus - with mailboxes that accept a lot > of spam and then forward it over to student / alumni AOL, Comcast, > Yahoo etc accounts > 2. Spam generated by infected PCs / laptops, hacked machines etc on > your campus LAN 3. Spammers abusing your webmail and/or remote message submission service using phished credentials. If your incoming spam blocks are effective then forwarding shouldn't be too much of a problem. For on-campus bots, block port 25 and ensure your MX servers can't be used as outgoing relays (i.e. put your outgoing relay service on a separate address). If you are lucky your colleagues chose a really obscure name (not mail.* or smtp.* etc.) for your outgoing relay service 20 years ago so spammers are less likely to guess it :-) To protect against phished accounts, apply rate-limits to outgoing email. If you have good on-campus security hygeine then you can be much less strict about the limits for on-campus connections. Tony. -- f.anthony.n.finch <[email protected]> http://dotat.at/ GERMAN BIGHT HUMBER: SOUTHWEST 5 TO 7. MODERATE OR ROUGH. SQUALLY SHOWERS. MODERATE OR GOOD.
