TP-Link TD-8840T User Manual page 28

Primary DNS Server/ Secondary DNS Server: Choose "Set DNS Server manually", you can
set DNS Server (at least one) manually here. The Route will use this DNS Server for priority.
Click the Save button to save the settings.
4.4.1.3 PPPoE
If your ISP provides a PPPoE connection and you need to use an ATM Interface, choose PPPoE
in the drop-down list, and then the screen will be displayed as below.
PPP Username/Password/Confirm Password: Enter the User Name, Password and
Confirm Password provided by your ISP. These fields are case-sensitive.
Authentication Method: Select the Authentication Method from the drop-down list, the
default method is AUTO_AUTH, and you can leave it as a default setting.
TD-8840T ADSL2+ Modem Router User Guide
Figure 4-6
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