title: How the request.getRemoteUser() works and the remote username value is stored?
body: <p>I have Tomcat authentication (form authentication) in my application. After successful authentication, I am able to get the username from the <code>request.getRemoteUser()</code> method in my servlet.</p>
  <p>Where I can find <code>request.getRemoteUser()</code> code? How does this work? Where has the RemoteUser has been set and stored? Since HTTP requests are stateless and execute independently, how this giving the username in all subsequent requests?</p>