D-Link DIR-822 User Manual page 56

Section 4 - Configuration
PPP
Enable this setting to connect without a username and password.
Without
This configuration is uncommon and is disabled by default.
authorization:
If Without authorization is disabled, specify the PPP username
Username:
provided by your ISP.
If Without authorization is disabled, specify the PPP password
Password:
provided by your ISP.
Specify the VPN server address provided by your ISP.
VPN Server
address:
D-Link DIR-822 User Manual 52