After selecting the Radius authentication method, you will need to provide the following information:
Enter the Authentication Server address.
Enter the server Port (the default is 1812).
Select a number of Server Retries.
Enter the shared key. (The shared key is the key received from the server administrator.)
Enter the shared key again by entering it in the Verify Shared Key field.
Once changes have been made to the settings in the dialog box, select Apply to save and exit the menu. Select Cancel to exit without making any changes.