Answer:
layered defense / defense-in-depth
Step-by-step explanation:
Layered defence is majorly used to describe a security system that is build using multiple tools and policies to safeguard multiple areas of the network against multiple threats including worms, theft, unauthorized access, insider attacks and other security considerations.
A layered defense at the same time is meant to provide adequate security at the following levels: system level security, network level security, application level security, and transmission level security.
Also called a multi-layered defense.