D-Link DFL-2500 - Manual (Page 228)

d. Port: 1812 (RADIUS service uses UDP port 1812 by default)
e. Retry Timeout: 2 (NetDefendOS will resend the authentication request to the sever if there is no
response after the timeout, for example every 2 seconds. This will be retried a maximum of 3 times)
f. Shared Secret: Enter a text string here for basic encryption of the RADIUS messages.
g. Confirm Secret: Retype the string to confirm the one typed above
3. Click OK
8.2.6. HTTP Authentication Chapter 8. User Authentication
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