php set time delays after input attempts -

php set time delays after input attempts -

question related brute forcefulness attacks. if user enters wrong password, php records in mysql datetime of attempt. , in case of wrong password need user can create next effort after time (1-2 seconds). understand php sleep not good, because not prevent bots create requests?

what solution (to set time delay without php sleep)?

you add together sleep @ origin of file if number of requests high user. maybe add together 1 sec every failed request in past 24 hours or exit if number reaches threshold.

<? //script find when lastly requests made if($failed>2) { sleep($failed+1); }elseif($failed>10) { exit;//or redirect } //the rest of file ?>

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