D-Link DI-304 User Manual page 46

DI-304/DI-304M ISDN Remote Router
To start ISDN Dial Backup function, you must create a dial backup profile. Click
Internet Access Setup → Dialing to a Single ISP to setup the backup profile.
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Dial Backup Mode – There are three options:
◊ None - Disable the backup function.
◊ Packet Trigger - The backup line is disconnected until a packet
from a local host triggers the router to establish a connection.
◊ Always On - If the broadband connection is no longer available,
the backup line will automatically connect and stay Always On until
the broadband connection is recovered.
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