Challenge / Response Spam Filtering

[EQ Admin]

Hello,

What do you think about challenge / response anti-spam systems? I am talking about services such as SpamArrest that send verification links back to the senders of e-mail. There are several pros and cons of such systems. For example, it may work well for the user of the service to help keep spam out of their inbox since a link click is required to have the e-mail delivered, but one of the major cons is that spammers rarely use a valid From: address so that link can end up going to an innocent person (you get spammed!) or they use the address of a commonly whitelisted e-mail address received by the masses. What are your opinions on this topic?

 

[Big Dan]

As a webmaster and someone who depends on email for a good majority of my work. I don't care for it.. How many times is someone going to trash that verification message and then I miss a clients call for help or potential new client. That who is to say some clunky mail service like AOL (which is famous for black holing messages) doesn't just blackhole it with out a notice to their customer.

 

[yukon]

personally I don't like it. I think its far more user friendly to blow out the bad (err spamassassin) from a mailbox, and let a user deal with the few that squeaked by than to use a challenge response system. Its basically an automated white list, and I think for many common users too complicated. Furthermore the peeps you really want to stop are just going to get their junk through another way (see "spammers rarely use a valid From:" in Ray's first post).