The HTTP_FloodControl package can be used to detect and protect a
Web site from attempts to flood it with too many requests. It also allows to
protect the site from automatic downloading many pages or files from the same
IP address, session ID or other unique identifier.

The detection of flood is determine according to a set of parameters indicating
the maximal allowed number of requests for the certain time interval. It is
possible to set several parameters at once in order to perform more effective
protection.

The package uses various storage containers (regular files, DB, MDB, MDB2) to
handle counter logs.

WWW: https://pear.php.net/package/HTTP_FloodControl