The Washington Post's Security Fix blog is reporting that Verizon, long identified as the largest ISP source of spam, is moving to require use of the submission port
, 587, in outbound mail — and thus to require authentication. While spammers may still be able to relay spam through zombies in Verizon's network, if the victims let their mail clients remember their authentication credentials, at least the zombies will be easily identifiable. Verizon pledges to clean up their zombie problem quickly. We'll see.