LevelOne Broadband VPN Gateway User Guide
IKE Exchange
Mode
Select the desired option, and ensure the remote VPN endpoint uses
the same mode. Main Mode provides identity protection for the hosts
initiating the IPSec session, but takes slightly longer to complete.
Aggressive Mode provides no identity protection, but is quicker.
IKE SA Life Time This setting does not have to match the remote VPN endpoint; the
shorter time will be used. Although measured in seconds, it is com-
mon to use time periods of several hours, such 28,800 seconds.
DH Group Select the desired method, and ensure the remote VPN endpoint uses
the same method. The smaller bit size is slightly faster.
IKE PFS If enabled, PFS (Perfect Forward Security) enhances security by
changing the IPsec key at regular intervals, and ensuring that each
key has no relationship to the previous key. Thus, breaking 1 key
will not assist in breaking the next key.
This setting should match the remote endpoint.
Click Next to see the following IKE Phase 2 screen.
Figure 53: VPN Wizard - IKE Phase 2
IKE Phase 2 (IPsec SA)
IPsec SA Life Time This setting does not have to match the remote VPN endpoint; the
shorter time will be used. Although measured in seconds, it is
common to use time periods of several hours, such 28,800 seconds.
IPSec PFS If enabled, PFS (Perfect Forward Security) enhances security by
changing the IPsec key at regular intervals, and ensuring that each
key has no relationship to the previous key. Thus, breaking 1 key
will not assist in breaking the next key.
AH Authentication
AH (Authentication Header) specifies the authentication protocol
for the VPN header, if used.
AH is often NOT used. If you do enable it, ensure the algorithm
selected matches the other VPN endpoint.
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