D-Link DFL-1660 User Manual page 372

9.4.6. IPsec Advanced Settings
Chapter 9. VPN
Tunnels if the latter is changed. This linkage is broken once IPsec Max Rules is altered manually
so that subsequent changes to IPsec Max Tunnels will not cause an automatic change in IPsec Max
Rules.
Default: 4 times the license limit of IPsec Max Tunnels
IPsec Max Tunnels
Specifies the total number of tunnels allowed by NetDefendOS. This value is usually taken from the
license but in situations where it is desirable to have less than the license value it can be reduced.
System memory for the tunnels is allocated at startup and reducing this value can therefore reduce
memory requirements.
A warning log message is generated automatically when 90% of this value is reached.
Default: According to the licensed limit
IKE Send Initial Contact
Determines whether or not IKE should send the "Initial Contact" notification message. This message
is sent to each remote endpoint when a connection is opened to it and there are no previous IPsec
SA using that gateway.
Default: Enabled
IKE Send CRLs
Dictates whether or not CRLs (Certificate Revocation Lists) should be sent as part of the IKE
exchange. Should typically be set to ENABLE except where the remote peer does not understand
CRL payloads.
Note that this setting requires a restart to take effect.
Default: Enabled
IPsec Before Rules
Pass IKE and IPsec (ESP/AH) traffic sent to NetDefendOS directly to the IPsec engine without
consulting the rule set.
Default: Enabled
IKE CRL Validity Time
A CRL contains a "next update" field that dictates the time and date when a new CRL will be
available for download from the CA. The time between CRL updates can be anything from a few
hours and upwards, depending on how the CA is configured. Most CA software allow the CA
administrator to issue new CRLs at any time, so even if the "next update" field says that a new CRL
is available in 12 hours, there may already be a new CRL for download.
This setting limits the time a CRL is considered valid. A new CRL is downloaded when
IKECRLVailityTime expires or when the "next update" time occurs. Whichever happens first.
Default: 86400 seconds
IKE Max CA Path
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