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Learn through experiments

Contain a fictional incident

How does a delay change affected devices and interrupted service?

Entering midway? Revisit Secure a tiny inventory handler for the preceding worked example, or start here and use the explanation below.

1 · Try

Start with a concrete question

Seven-device tabletop scenario with explicit spread timing and isolation options.

Try the initial inputs, then write a prediction before changing one setting. All calculations run locally on your CPU.

Go directly to the experiment · Review basic mathematics

2 · Predict

What do you expect?

Before changing a setting: How does a delay change affected devices and interrupted service? Write what you expect and why.

3 · Experiment

Change one thing. Inspect what happens.

  1. Predict affected devices at minute 4.
  2. Compare targeted and whole-network isolation at the same delay.
  3. Move the delay to a spread boundary and inspect event order.
  4. Write an incident timeline, owner and restoration check.
Experiment inputs
Inputs
Your settingsMechanism
Calculation belowEvidence
Compare outcomes
Affected devices7 devices
Devices disconnected0 devices
Device-hours unavailable0 device-hours

Compare the current results

Every bar starts at zero and uses the same numeric scale in this chart. The upper bound automatically adjusts to the largest current value (at least 1), so compare the numbers when changing inputs. Units and quantities come from each label; different kinds of quantity are not interchangeable. Displayed values are rounded to at most six significant digits.
07
  • Affected devices (devices)7
    Affected devices (devices): 7Horizontal bar from zero to 7, on the shared zero to 7 numeric axis.
  • Devices disconnected (devices)0
    Devices disconnected (devices): 0Horizontal bar from zero to 0, on the shared zero to 7 numeric axis.

Follow the calculation

  1. At minute 0, one infected device is discovered. Every two minutes it compromises one more device, up to seven.
  2. Action at minute 4; a spread event at that minute happens before isolation.
  3. Policy: observe only until minute 12.
  4. Spread stops at minute 12. Secondary devices do not spread in this fixture. Restoration takes three hours per disconnected device in parallel.

Containment trades interrupted service against additional exposure; document timing and the assumptions about spread.

Captures keep your inputs, prediction and observation. Results are recalculated from those inputs. Resetting inputs keeps your captures and challenge history.

4 · Understand

Explain the mechanism

Contain a fictional incident

Seven-device tabletop scenario with explicit spread timing and isolation options.

Follow the mechanism

At minutes 2 and 4 another device is affected, so action at minute 4 follows three infections.

Parallel restoration means three elapsed hours but more device-hours when more devices are disconnected.

Containment assumes secondary devices cannot spread; revise the plan if that assumption fails.

Worked example

At minute 0, one infected device is discovered. Every two minutes it compromises one more device, up to seven.

Action at minute 4; a spread event at that minute happens before isolation.

Policy: observe only until minute 12.

Spread stops at minute 12. Secondary devices do not spread in this fixture. Restoration takes three hours per disconnected device in parallel.

Calculation

Affected = min(7, 1 + floor(spread minutes/2)); unavailable device-hours = disconnected devices × 3.

Try a controlled comparison

  1. Predict affected devices at minute 4.

  2. Compare targeted and whole-network isolation at the same delay.

  3. Move the delay to a spread boundary and inspect event order.

  4. Write an incident timeline, owner and restoration check.

What this does not establish

  • All messages, people, documents and outcomes here are original fictional teaching fixtures; results are not measurements of real organizations.
5 · Apply

Try a fresh case

Four isolated devices each remain unavailable for two hours in parallel. How many device-hours are lost?

This is a public practice check. Retries support learning; matching a number does not certify independent proficiency.

Take the investigation further

Choose any extension. These are project prompts for you to carry out; they are not automatically assessed.

School investigation

Create a new case with different numbers and explain your decision to a classmate.

College investigation

Implement or analyze a fresh case, document assumptions and compare at least two alternatives.

Workplace investigation

Prepare a decision artifact with evidence, operating constraints, an owner and a follow-up measurement.

6 · Continue

Keep the evidence, choose your next step

Completion records your own decision that you have worked through this investigation. Practice checks and independent project evidence are separate.