Protect access without losing recovery
Which policy rejects a stolen password while supporting a legitimate recovery?
Entering midway? Revisit Inspect before you follow for the preceding worked example, or start here and use the explanation below.
Start with a concrete question
Fictional sign-in and offline-code scenarios. No real credentials are collected.
Try the initial inputs, then write a prediction before changing one setting. All calculations run locally on your CPU.
What do you expect?
Before changing a setting: Which policy rejects a stolen password while supporting a legitimate recovery? Write what you expect and why.
Change one thing. Inspect what happens.
- Test an attacker with only a password.
- Test the owner who lost a device.
- Explain the separate-storage assumption for recovery codes.
- Write a recovery checklist that includes identity verification.
Your settingsMechanism
Calculation belowEvidence
Compare outcomes
Follow the calculation
- Policy: password alone.
- Event: attacker has only password.
- The fixture assumes the attacker cannot access the second factor or recovery code, and the owner keeps the recovery code separately.
Account protection must consider recovery as well as normal sign-in. A recovery route can preserve access, but its own protection matters.
Captures keep your inputs, prediction and observation. Results are recalculated from those inputs. Resetting inputs keeps your captures and challenge history.
Explain the mechanism
Protect access without losing recovery
Fictional sign-in and offline-code scenarios. No real credentials are collected.
Follow the mechanism
A second factor adds a requirement that possession of a password alone does not satisfy.
Recovery restores legitimate access but introduces another sensitive route.
The fixture assumes independent protection; compromise of both factors is outside it.
Worked example
Policy: password alone.
Event: attacker has only password.
The fixture assumes the attacker cannot access the second factor or recovery code, and the owner keeps the recovery code separately.
Calculation
Access depends on policy and available factors; authorized success and unauthorized success are counted separately.
Try a controlled comparison
Test an attacker with only a password.
Test the owner who lost a device.
Explain the separate-storage assumption for recovery codes.
Write a recovery checklist that includes identity verification.
What this does not establish
- All messages, people, documents and outcomes here are original fictional teaching fixtures; results are not measurements of real organizations.
Try a fresh case
A review finds 18 users have a protected recovery method and 7 do not. How many of the 25 users need a recovery plan?
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.
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.