FINESEC

SiteDefensor supports a cluster setup with nginx servers working as data nodes.
SiteDefensor provides password sharing detection (IP+geolocation) and anti-leeching protection.

PS. You might want to use apache 2.4 event MPM (it can handle like 20k static requests per second without a problem).

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http://SiteDefensor.com - secure authentication, password cracking and sharing prevention, site ripping protection
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