Draytek Vigor2830 Series User Manual page 240

The window of advance setup is shown as below:
IKE phase 1 mode -Select from Main mode and Aggressive
mode. The ultimate outcome is to exchange security proposals
to create a protected secure channel. Main mode is more secure
than Aggressive mode since more exchanges are done in a
secure channel to set up the IPSec session. However, the
Aggressive mode is faster. The default value in Vigor router is
Main mode.
IKE phase 1 proposal-To propose the local available
authentication schemes and encryption algorithms to the VPN
peers, and get its feedback to find a match. Two combinations
are available for Aggressive mode and nine for Main mode. We
suggest you select the combination that covers the most
schemes.
IKE phase 2 proposal-To propose the local available
algorithms to the VPN peers, and get its feedback to find a
match. Three combinations are available for both modes. We
suggest you select the combination that covers the most
algorithms.
IKE phase 1 key lifetime-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.
IKE phase 2 key lifetime-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 Secret (PFS)-The IKE Phase 1 key will be
reused to avoid the computation complexity in phase 2. The
default value is inactive this function.
Local ID-In Aggressive mode, Local ID is on behalf of the IP
address while identity authenticating with remote VPN server.
The length of the ID is limited to 47 characters.
Vigor2830 Series User's Guide
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