What is the status of OS Identification?

A.
It is only enabled to identify “Cisco IOS” OS using statically mapped OS fingerprinting

B.
OS mapping information will not be used for Risk Rating calculations.

C.
It is configured to enable OS mapping and ARR only for the 10.0.0.0/24 network.

D.
It is enabled for passive OS fingerprinting for all networks.

Explanation:
Understanding Passive OS Fingerprinting Passive OS fingerprinting lets the sensor determine the
OS that hosts are running. The sensor analyzes network traffic between hosts and stores the OS
of these hosts with their IP addresses. The sensor inspects TCP SYN and SYNACK packets
exchanged on the network to determine the OS type. The sensor then uses the OS of the target
host OS to determine the relevance of the attack to the victim by computing the attack relevance
rating component of the risk rating. Based on the relevance of the attack, the sensor may alter the
risk rating of the alert for the attack and/or the sensor may filter the alert for the attack. You can
then use the risk rating to reduce the number of false positive alerts (a benefit in IDS mode) or
definitively drop suspicious packets (a benefit in IPS mode). Passive OS fingerprinting also
enhances the alert output by reporting the victim OS, the source of the OS identification, and the
relevance to the victim OS in the alert. Passive OS fingerprinting consists of three components:
•Passive OS learning Passive OS learning occurs as the sensor observes traffic on the network.

Based on the characteristics of TCP SYN and SYNACK packets, the sensor makes a
determination of the OS running on the host of the source IP address. •User-configurable OS
identification You can configure OS host mappings, which take precedence over learned OS
mappings. •Computation of attack relevance rating and risk rating