title: Java EE Security Realms
body: <p>Reading the Java EE security docs, where they define a <strong>security realm</strong> to be:</p>
  
  <blockquote>
    <p>An access channel for the application server to storage containing user's authentication and grouping information.</p>
  </blockquote>
  
  <p>What do they mean by "access channel"? Is this a port number, or some sort of networking term? And what do they mean by "authentication/grouping information"? Permissions?</p>
  
  <p>I'm just looking for some concrete (non-vague) examples here! Thanks in advance!</p>