Draytek Vigor2760 User Manual page 270

There are several options offered in default. If you click the "-"
button to remove one of them, a "+" button will appear to let
you add another one option instead.
Phase2 –It is available if Custom for IKE Proposals is
selected above. Use the drop down list to choose values for
Cipher and Hash.
Phase1 DH Group / Phase2 DH Group –It is available if
Custom for IKE Proposals is selected above. Both parameters
are used to choose the length of the session key. The more the
length is, the safer the data transmission will be. However, the
time to generate the security key will be long.
Phase1 Key Lifetime (min) –For security reason, the lifetime
of key should be defined. The default value is 28800 seconds.
You may specify a value in between 900 and 86400 seconds.
Phase2 Key Lifetime (min) –For security reason, the lifetime
of key should be defined. The default value is 3600 seconds.
You may specify a value in between 600 and 86400 seconds.
Perfect Forward Secrecy (PFS) –The IKE Phase 1 key will
be reused to avoid the computation complexity in phase 2. The
default value is inactive this function.
Dead Peer Detection –Action – This function will detect if
any response received from the peer. If no response, the chosen
action will be performed. Hold means such VPN connection is
still active; Clear means such VPN connection will be down.
Vigor2760 Series User's Guide
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