What is the most common way to classify IDSs?

A.
Group them by information source.
B.
Group them by network packets.
C.
Group them by attackers.
D.
Group them by signs of intrusion.
Explanation:
The most common way to classify IDSs is to group them by information source. Some IDSs analyze
network packets, captured from network backbones or LAN segments, to find attackers. Other IDSs
analyze information sources generated by the operating system or application software for signs of
intrusion.