D-Link DIR-825 - Manual (Page 81)

 D-Lnk DIR-825 User Manual
Secton  - Securty
8. Next to RADIUS Server Port, enter the port you are using with
your RADIUS server. 1812 is the default port.
9. Next to RADIUS Server Shared Secret, enter the security
key.
10. If the MAC Address Authentication box is selected then the
user will need to connect from the same computer whenever
logging into the wireless network.
11. Click Advanced to enter settings for a secondary RADIUS
Server.
12. Click Apply.Settings to save your settings.