Responding appropriately to an incident requires understanding
how incidents occur and what symptoms may indicate that an
event has occurred. To do that, you also need the right tools and
techniques. In this chapter, you will learn about three major
categories of symptoms. First, you will learn about network
events, including malware beaconing, unexpected traffic, and
link failures, as well as network attacks. Next, you will explore
host issues, ranging from system resource consumption issues to
malware defense and unauthorized changes. Finally, you will
learn about service- and application-related problems.