(Optional) Configuring the Heartbeat Detection Function for the Built-in Portal Server

When a user closes the browser or an exception occurs, the device can detect the user's online state to determine whether to make the user go offline. The administrator can configure the heartbeat detection function of the built-in Portal server. If the device does not receive a heartbeat packet from the client within a specified period, the user is specified to go offline. The heartbeat detection mode of the built-in Portal server can be either of the following modes:

• Forcible detection mode: This mode is valid for all users. If the device does not receive a heartbeat packet from a user within a specified period, the device specifies the user to go offline.
• Automatic detection mode: The device checks whether the client browser supports the heartbeat program. If yes, the forcible detection mode is used for the user; if no, the device does not detect the user. You are advised to configure this mode to prevent users from going offline because the browser does not support the heartbeat program.
  

  Currently, the heartbeat program is supported by Internet Explorer 8, FireFox 3.5.2, Chrome 28.0.1500.72, and Opera 12.00 on Windows 7. A Java program must be installed and configured on the operating system.

  Browsers using Java1.7 and later versions do not support the heartbeat program.