# How Site Authorization Works The diagram below demonstrates calls sequence made during user's authentication: 1. Once loaded Chat sends a request over TCP to chat server. The request contains UID parameter to be used for further authentication. 2. Java Server makes HTTP call to handler located on web server (your website). 3. Handler generates XML formatted response containing all user's profile data and returns output xml back to java server. 4. Chat receives full information about the user. In case authentication fails for the user and step #3 returns corresponding error, a warning window appears with notification for the user. In the following sections we will cover each step in more detail.