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Cybersecurity module

System ilities

Security design becomes brittle when it ignores the other properties a live system needs in order to keep serving people well.

  • Practice & Strategy
  • 17 min
  • 2 outcomes

Optional progress

Record completion if you need it

What changes after this module

Balance security with reliability, maintainability, resilience, performance, and recoverability so the system stays usable under stress.

Outcome promise

  • Explain why security has to be balanced with other system qualities.
  • Identify one trade-off between security and another quality attribute.

Core model

Use the diagram and terms below as the minimum model you should be able to explain after this module. If you cannot explain the model in plain language, pause here before you move on.

System ilities
A single visual model so the concept stays connected to a real decision.
Service andobligationControls andtrade-offsEvidence andaudit trailReview andresilienceprotectshowgovernadapt and recover

Key terms

Resilience
The ability to absorb disruption and continue or recover service.
Maintainability
How easily a system can be updated, repaired, and understood over time.

Check yourself

Answer the prompt before you reveal the check. If you cannot answer it in your own words, revisit the model and the terms once more.

Quick check

Why can an apparently strong security control still weaken the overall system?

Reveal the answer check

Because it may reduce operability, recoverability, visibility, or maintainability so much that the service becomes harder to keep safe in reality.

Reflection and evidence

Keep the evidence small. One honest reflection and one small artefact is enough to show that the learning changed how you describe, check, or design something.

Reflection prompt

Think of one control you know. Which other system quality does it strain, and how would you balance that better?

Artefact

A trade-off note that names one control, one affected quality, and the balance you would choose.

Optional deeper practice

Use the workspace to compare two design options and decide which one gives the best balance of security and operational quality.

Move through the course

Keep the flow predictable. Stay with the stage sequence unless you have a clear reason to jump around.