CAPTCHA

According to Wikipedia:

A CAPTCHA is a type of challenge-response test used in computing as an attempt to ensure that the response is generated by a person. The process usually involves a computer asking a user to complete a simple test which the computer is able to generate and grade. Because other computers are assumed to be unable to solve the CAPTCHA, any user entering a correct solution is presumed to be human. Thus, it is sometimes described as a reverse Turing test, because it is administered by a machine and targeted to a human, in contrast to the standard Turing test that is typically administered by a human and targeted to a machine.

A common type of CAPTCHA requires the user to type letters or digits from a distorted image that appears on the screen.

In PRPC, a CAPTCHA may appear on the login screen when the user first attempts to log into the system from a given computer or after an authentication failure, and on the password-change screen. This helps counter "brute-force" automated attacks on system security.

You can enable and customize CAPTCHA functions in the Security Policies landing page tab:

> System > Settings > Security Policies.

System category — System Settings landing page

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