Asus 4G-AC68U User Manual page 17

for PPPoE, PPTP, and L2TP
for Static IP
6. If a 3G/4G network is connected, the wireless router's Quick
Internet Setup (QIS) feature automatically detects and applies
the APN setting to connect to the wireless base station. If the
QIS wizard failed to automatically apply the APN setting or
the SIM card prompts for a PIN code, set up the APN setting
manually.
NOTE: The PIN code may vary from different providers.
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