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Figure 6-3: IPSec Policy Options
Settings
– IPSec Policy Options
Dead Peer Detection
Feature
Dead Peer Detection (DPD)
–
If
set to
Enable
,
a device will
periodically send HELLO/ACK messages to check if the tunnel is
alive when both peers of a VPN tunnel provide DPD mechanism.
Once a dead peer is detected, a device will end the connection so it
can be re-established. This is the primary method of VPN failover or
backup.
Detection
–
If set to
Enable
,
this will enable the following Check
Method which you have selected to work:
Check Method
:
1.
Heartbeat
–
Sends
a unidirectional („
HELLO’
only) message to
determine connection aliveness.
2.
ICMP Host
–
It uses
ICMP
packets to determine connection
