Facilitator Notes & Model Answers — Lesson 10
For instructors and self-study · Model review and rationale
Model foundations review — Meridian
| Pillar | Gap | Improvement |
|---|---|---|
| Zero trust | Flat network; one breach spreads freely | Segment the network; verify identity per request; strip over-broad access |
| Cloud | No owner for configuration; unknown exposure | Assign a configuration owner; check against a hardened baseline; gain visibility of what's running |
| Cryptography | Key management never reviewed; long-lived secrets unprotected against future decryption | Review key handling; inventory long-lived secrets; begin crypto-agility toward post-quantum |
| Supply chain | Two small suppliers with deep access; no SBOM or audit | Map supplier access; set minimum security requirements; obtain software provenance/SBOM |
Why the poll answer is C (inventory + begin migration)
- A — do nothing: ignores that data stolen now can be decrypted later; long-lived secrets are exposed today.
- B — wait for standards: post-quantum standards already exist, and migration is multi-year — waiting extends the exposure window.
- C — inventory long-lived secrets and start planning: you cannot migrate what you have not identified; crypto-agility first, then algorithm change. The correct sequencing.
- D — stop encrypting: reckless; encryption still protects against every non-quantum adversary today.
Teaching point: "not urgent" is the trap. For anything with a long confidentiality lifetime, the harvest-now threat makes it urgent now.
Homework — what good looks like
Task 1
Strong answers name a specific flat-network or over-broad-access reality and a cloud-configuration ownership gap, not generic "improve security."
Task 2
The best answers pair a concrete long-lived-secret category (e.g., legal, strategic, personal-safety data) with a per-supplier access statement.
Task 3
Good questions force evidence: "Show me our cloud baseline and the last exposure check," not "Are we secure in the cloud?"