CISSP Practice Question – Domain 4 (Secure Network Design & Key Management)
A multinational enterprise operates a highly distributed microservices architecture across multiple cloud providers.All traffic between microservices must be encrypted and authenticated. To simplify governance, the company wants a single global certificate hierarchy for all workloads across all clouds and on-prem systems. However, several constraints apply: - Private keys must never leave the host or container where they are created. - Certificate issuance must support auto-scaling, ephemeral workloads, and identity rotation every few minutes. - The environment includes legacy systems that cannot use modern service mesh sidecars. - Security monitoring requires centralized revocation and trust-state visibility across all issuers. Which PKI architecture BEST satisfies these requirements? A. single monolithic root CA issuing certificates directly to all cloud and on-prem workloads. B. Multiple independent PKIs, each cloud provider managing its own root and workload certificates. C. A federated PKI with one offline enterprise root and cloud-specific subordinate CAs, each issuing short-lived, locally generated keypairs. D. Use self-signed certificates generated per workload and synchronize fingerprints centrally for trust verification.