4. Methodology for developing a functional defense plan

4.1 General

Designing a defense plan is no easy matter: as we have seen, major incidents involve a multitude of events, complex phenomena and high stakes. In this context, the methodology used to develop a defense plan is a key factor in its effectiveness.

• Two approaches are used to develop functional defense plans.

  • Phenomena-based approach: we know the general characteristics of the phenomena we wish to defend against. We define a general defense barrier adapted to the entire network.

  • The incident-based approach: we want to defend against a specific incident. A specific defense barrier is developed to protect only against this particular...