Nokia IP60 User Manual page 94

Using Internet Setup
In this field... Do this...
Dead Connection
Detection
Probe Next Hop Select this option to automatically detect loss of connectivity to the default
gateway. If you selected LAN, this is done by sending ARP requests to the
default gateway. If you selected PPTP, PPPoE, or Dialup, this is done by
sending PPP echo reply (LCP) messages to the PPP peer.
By default, if the default gateway does not respond, the Internet
connection is considered to be down.
If it is determined that the Internet connection is down, and two Internet
connections are defined, a failover will be performed to the second
Internet connection, ensuring continuous Internet connectivity.
This option is selected by default.
94 Nokia IP60 Security Appliance User Guide