title: Licensing modules on a web-application
body: <p>Let's say that you have a Web Site that has a bunch of different modules to it such as:</p>
  
  <ul>
  <li>Accouting ( Handle customers, invoices, etc )</li>
  <li>Notes and Documents ( Create and Manage your documents )</li>
  <li>Many more..</li>
  </ul>
  
  <p>How would you restrict access one of the <em>"Modules"</em> if one customer does not have the appropriate license?</p>
  
  <p>I've often seen components that comes with a <code>.lic</code> file, how do you generate one of those?</p>
  
  <p>And if you use a method like that does it affect performance?</p>
  
  <p><strong>Edit</strong></p>
  
  <p>Another thing I was thinking about, if you ship all modules with your application and you only want to show the controls that you have licensed, do you need to check each control for validity or can you somehow extract that information?</p>