Start by clarifying requirements: scale, security, and operational constraints. Then propose a two-tier CA hierarchy (offline root, online issuing CAs) with automated certificate lifecycle management. Finally, discuss extensions for user/device certificates and code signing, emphasizing trade-offs and integration with existing systems.
Pro tip: Emphasize automation and short-lived certificates to reduce operational burden and improve security; mention tools like cert-manager, Vault, or step-ca as practical solutions.
Ask about scale (number of services, certificates), security requirements (key protection, revocation), and operational constraints (existing tools, cloud provider).
Propose a two-tier PKI: offline root CA and online issuing CAs (possibly per environment or region). Discuss key ceremonies and HSM usage.
Outline automated issuance, renewal, and revocation using protocols like ACME or EST. Highlight short-lived certificates and monitoring.
Explain how to extend the PKI for user/device certificates (e.g., via SCEP or MDM) and code signing (separate CA, timestamping).
Compare build vs. buy, cloud vs. on-prem, and integration with service mesh, Kubernetes, or CI/CD pipelines.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.