D-Link NetDefendOS User Manual page 565

Chapter 6: Security Mechanisms
The IDP signature database can be updated automatically and certain signatures can be dropped
or updated and new signatures introduced. In some cases, it can be preferable to force the
database update manually so that the effect of any changes can be observed following the
update.
Automatic updates might take place without the necessary checking in place to make sure there
are no disruptions to live traffic.
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