IP Addresses are NOT Unique

Developers are always looking for better ways to uniquely identify clients, and many try to use the remote IP address (which you can get from a CGI variable) for this purpose. Unfortunately, this does not work safely, IP addresses can never be assumed to be unique. Why? Different users of some online services often share the same IP address (or appear to do so). Similarly, users behind a proxy server or firewall might appear to you as the same IP address. As such, assuming IP addresses are unique is asking for trouble. (Applies to: ColdFusion All)

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