D-Link DAP-1665 User Manual page 47

Section 3 - Configuration
Advanced: Click on the Advanced button to display the setup options for
an optional backup RADIUS server configuration.
Second RADIUS
Enter the IP address for your network's backup RADIUS
Server IP
authentication server.
Address:
Second Pre-
Enter the port for the backup RADIUS authentication server.
Shared Key:
Second Radius
Enter the shared secret required by the backup RADIUS
Server Shared
authentication server.
Secret:
Click Save Settings at the top of the page to save the current
configuration.
D-Link DAP-1665 User Manual 47