title: How to generate unique licence key for particular IP address in PHP script?
body: <p>I made a PHP script. Now I want to generate unique random licence key for a particular client for a particular IP address.
  I want strong security for licence key like ie.If client install script in particular IP address or particular domain then he can't instal the same script on another machine or another domain with same licence key.<strong>what is the logic or coding</strong> when client install script only one domain or only one ipaddress..client cant install script on another machine or anther ipaddress or another domain. </p>
  
  <p>Please give me some ideas or code for generating such a licence key in PHP. </p>