Only because I was up checking on a remote problem...
This is the future of e-mail, if something better at spam suppression doesn't come along.
Like the Delete function? what's NOT better than easily duped validation mechanisms? Perhaps the only reason spammers haven't bothered is because adoption rates are so low. Consider: 1) in order to reduce annoyance, systems validate essentially ONCE. At best, they're going to validate once a month or so. 2) it's trivial these days to register a fresh domain and enter auth servers. Fraudulent registrations are already common. 3) DHCP assignments on broadband are *just* stable enough that someone can setup some verifiable servers and send some mostly mundane messages 4) it's technically trivial to collect verify responses and direct things into a bot that senses a validation system and replies(via email or web, either is a well-known pattern that MUST remain valid once deployed to customer sites, to be useful to the customers) as needed. 5) it'll take longer to clean these out of your validation system than it will for them to move onto another domain that's newly in(hours). All you've really down is open up your whitelisting policy to the outside world. Well, that and tie up more system resources to manage the database. Now ask yourself how you're going to track down a validated server that went away, to be replaced by more spam from 0wned systems. Your own protection system has opened the door. You think getting help stopping a DDOS in progress is bad? And of course, the folks you're asking for help are the ones getting spammed by your validation email to begin with. Congratulations. If these annoying systems become widespread, very smart people with more time than us to work on it will have no trouble defeating them.
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-- Ray Wong rayw@rayw.net