Control Distributed Smart Devices and Display Live Power Usage

Design a system that receives instructions to reduce electricity usage and sends them to smart devices across different locations. Handle devices that are offline. Add a feature that displays their real-time electricity consumption. ### Clarifying Questions Define the command's target scope, requested reduction semantics, validity window, device capabilities, and acknowledgment requirements. Clarify whether telemetry represents instantaneous power or accumulated energy, and what freshness qualifies as real time. No numeric scale, control deadline, or exact reduction policy is supplied; state any chosen assumptions. ### What a Strong Answer Covers Command ingestion and distribution, device identity, offline recovery, ordering and idempotency, acknowledgment versus actual effect, telemetry ingestion, freshness-aware dashboards, and operational visibility. ### Follow-up Questions - Should a device execute an old reduction command immediately after reconnecting? - How do you distinguish command delivery from a measured reduction in consumption? - What should the dashboard display when telemetry stops arriving?