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This isn’t a CAPTCHA. A CAPTCHA should be something that can tell a human user apart from a non-human user with a high degree of accuracy, such that it should b
by nneonneo 4y ago
This isn’t a CAPTCHA. A CAPTCHA should be something that can tell a human user apart from a non-human user with a high degree of accuracy, such that it should be hard for a bot to pass even a single instance.
As noted elsewhere in the thread, this is a rate-limiting system. It cannot protect low-rate critical resources like registrations, but would be useful in mitigating large-scale spam attacks.
- csense 4y agoAccording to Wikipedia, CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart. This code shouldn't be called CAPTCHA as it makes no attempt to tell humans from machines. (If anything, SHA256 proof-of-work is a problem that's easy for a computer but hard for a human, the opposite of a Turing test.) I'd call it "Proof-Of-Work Client-side RAte Protection" -- it's a POWCRAP, not a CAPTCHA. (I invented the acronym just now in this post; it could perhaps use some work.)
- waynesonfire 4y agoCRAP is sufficient