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quiz vs the machine

Gold1360

Security

Defense In Depth

Layering independent controls so one failure does not cause a breach.

4 min read · core · beat Gold to climb

The Strategy

Defense in depth layers multiple independent security controls so that if one fails, others still protect the system. No single barrier is assumed perfect, so an attacker must defeat several to succeed.

Layers To Combine

  • Network controls like firewalls and segmentation limit reach.
  • Application controls like input validation and output encoding stop injection.
  • Identity controls like strong authentication and least privilege limit access.
  • Monitoring detects and responds when prevention fails.

Why It Works

  • Independent layers mean a single bug or misconfiguration is not fatal.
  • It buys time to detect and respond before an attacker reaches critical assets.
  • It reduces reliance on any one control being flawless.

Key idea

Defense in depth layers independent controls so a single failure is contained, combining network, application, identity, and monitoring safeguards.

Check yourself

Answer to earn rating on the learn ladder.

1. What is the core idea of defense in depth?

2. Why include monitoring as a layer?