Form Spam Bot Blocker generates hidden inputs for forms that have special values that are verified on the server after the form is submitted to eventually detect whether the form was sent by a spam robot. A hidden input, containing an encoded value of the user browser, IP address and current time, is generated.

Form Spam Bot Blocker verifies whether these browser name and IP address are still the same, and also whether the form is being submitted by a normal time interval after it was create, like when it is submitted by a real human user. It also generates a text input that are invisible for the user. A human user would not fill this input. If the input is submitted with a value, it was certainly a robot.

When Form Spam Bot Blocker detects a situation that demonstrates the form was submitted by a robot, the application should not accept the form submission.

Requirements:
PHP 4.0 or higher