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I need a process to allow only certain computer systems access to the website irrespective of the network they are using.
Much like a Licensing system, I can provide a private key or something similar to the user, which the host server should identify that key by matching from a list of private key. Alternatively could the website hosting server can use the MAC address of system?
Client Machine can have any OS installed. I am familiar with PHP but open to using any programming language
Any ideas are welcome