The title may be a bit misleading, but essentially what I have is a custom CMS I built in PHP. What I want to do next is to build some sort of authentication to ensure my code was not copied and reused on another server.
I need some way to communicate between my CMS and an external script to ensure that it is valid.
I was thinking of putting a file on a domain. A simple function that accepts an url this function takes the url, searches the db, if it finds it, send back an result.
My CMS obviously queries this function with the current url of the domain and if the url is in my db, the software works, otherwise it displays a message saying it was illegally copied.
How do I build this interaction between the two? I could use AJAX, but i need something a bit more robust so that your average developer doesn't figure it out too easily.