The Defense-in-depth Model

In this chapter we will we discuss the methodology behind securing an ICS with a layered defense approach, the defense-in-depth model. You will learn the concepts creating a holistic ICS security posture by stacking our defenses, or in other words, by creating multiple backup security controls that cover and overlap each other. The following topics will be discussed in this chapter:

• Defense-in-depth
• ICS physical/network/computer/application/device security
• Layered defense