Top Deliverability’s Blog
Spam Resource: Challenge/Response still exists, and it’s still a problem
- November 17, 2022
- Posted by: Top Deliverability
- Category: Industry News Spam Resource
Al Iverson just shared a new insightful story on Spam Resource:
Challenge/Response is a specific type of email filter. If you use a Challenge/Response (C/R) spam filter to protect yourself from spam, here’s what happens:Your email server or service receives a new inbound email message.The system checks to see if this is a person that you’ve talked to before.If yes, the mail is forwarded to you, skipping the challenge step.If no, the mail is NOT forwarded to you, and the sender receives a notification back — a “challenge.”The notification encourages the sender to “respond” to the “challenge” by clicking a link, solving a puzzle (think CAPTCHA) or (this is a new one I’ve seen recently) paying a designated charity.The charity angle might be new; but C/R has been around forever. I know well how it works, having built my own implementation of it back in the late 1990s. And I’ve been pointing out the imperfections behind the concept since all the
Read the original here: Challenge/Response still exists, and it’s still a problem
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