Mod_Protection is an apache module that integrate basic function of an IDS (intrusion detection system) and of a firewall (not yet). Your apache administrator have only to install mod_protection and define rules. When a malicious client sends a request that matches on your rules the administrator will be warned and the client gets a user defined page or a error or something that notifies that now he will be persecuted or ... The warning system just write on a socket, so you can put on the other side of the socket an application that send you a mail, an SMS, a message in your favorite IM or a notify in your IRC client.
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