API Key and Token Service · View 06 of 22 · Act 3 · Structure
The load-bearing layer
- Propagation is the layer a first draft omits. Without it the choice is between a network call on every request and a credential that cannot be revoked; with it, neither.
- The staleness heartbeat is in this layer rather than in observability, because its absence changes behaviour rather than raising a ticket.
Reading the direction
- Control plane writes downward into state; propagation carries state sideways into the data plane; the data plane reads and emits telemetry. No verification ever calls upward.
- The cryptographic base is drawn beneath state deliberately: the pepper is not in the store it protects.
