What is the default action of a NetScreen firewall when a configured screening function threshold limit has been reached?
A.
Log the packet but not drop it
B.
Drop the packet and all further packets matching the attack for up to 1 minute
C.
Drop the packet and all further packets matching the attack for up to a configurable maximum of 10 seconds
D.
Drop the packet and all further packets matching the attack for the remainder of the current second plus the next second
Explanation:
The SCREEN options on a NetScreen firewall are perhaps the oldest form of protection found on these firewalls. New options and features were added over time to address new threats present on the Internet.
In the newer versions of ScreenOS (starting with ScreenOS 3.1, which was a limited-platform release-all
devices supported this new feature in ScreenOS 4.0), these options are securityzone specific-each zone may have unique settings applied to it. For all options, these settings are applied as the inspected traffic externally enters the zone-that is, when the stream is read from the interface off the wire, not as it passes through the NetScreen and out another interface.
While NetScreen organizes these attacks by layers and protocols, it’s easier to talk about them more generically by their purpose.The two major functions of the SCREEN features are reconnaissance detection and Denial of Service protection. The default threshold action for these features are : Drop the packet and all further packets matching the attack for the remainder of the current second plus the next second.