Q:

How to make sure PHP Scripts are only used on one machine by a client?

I have a set of PHP scripts sitting on several clients servers and I want to get the mac address for that server so that I can store it and determine that the PHP scripts are not being used on another server.
How can I get the Mac address of a computer using PHP somehow?
Is there a better way to determine if the PHP scripts are being used on a different machine?
Thanks all

A:

I don't think there is an easy way to get a MAC address from a visiting PC, but I'm not sure about that.
How about a simpler way: use a session? 
Just assign a session if there is none, you'll end up with one per machine (unless they use different browsers). You could lock the execution to that.
It's not as "perfectly secure" as locking on MAC, but still goes a long way...

