How to restrict the response of a jQuery.getJSON() only to certain domains?

Question

I have a jQuery script in a clientDomain.com/show.php page that shows some data loaded from a serverDomain.com/echo.php page using jQuery.getJSON(). I want that only allowed domains can show the data because I don't want that unauthorized people install the script in their own website without my permission. Is there any way to restrict the response of a jQuery.getJSON() only to certain domains? The solution should prevent also the use of iframe by the client. In conclusion, the data should be seen only if someone visit directly serverDomain.com/echo.php page or one of the allowed client domains. Thanks in advance for the support!

My request/response script works like the first example in jQuery.getJSON() | jQuery API Documentation

I can only code the client jQuery script (that will be ditribuited to the allowed domains) and the serverDomain.com/echo.php page (that is my property).

Answer 1

Don't do that. Use auth tokens instead that are updated regularly. Anybody can fake an HTTP referrer.

Here's a good answer on SO which covers resful api authentication: REST API Token-based Authentication