AOFS systems rely on robust, flexible communication protocols to connect Field, Farm, and HQ controllers, as well as sensors and actuators.
Protocols are selected based on range, power requirements, reliability, and operational constraints
1. Overview
Communication is layered:
Field Controller Layer: short-range, low-power, real-time sensor and actuator connectivity
Farm Controller Layer: aggregation, supervisory control, and moderate-range communication
HQ / Federated Layer: long-range, optional cloud or networked data aggregation and research integration
Protocols are optional, configurable, and modular
All protocols must respect AOFS principles:
Offline-first operation
Safety-critical logic cannot be overridden remotely
Actions are auditable and logged
2. Recommended Protocols
MQTT – lightweight publish/subscribe messaging for telemetry and asynchronous updates
AMQP – robust messaging with guaranteed delivery, suitable for HQ/Farm Controller links
Zigbee – low-power mesh networks for local sensors and actuators
LoRa / LoRaWAN – long-range, low-power communication suitable for large farms and sparse sensor deployments
Z-Wave – low-power mesh for home/farm automation devices and actuators
EnOcean – energy-harvesting wireless sensors and switches
3. Layer Mapping Guidance
Field Controller Layer
Zigbee, Z-Wave, EnOcean for sensor/actuator connectivity
MQTT for telemetry aggregation to Farm Controller
Farm Controller Layer
MQTT or AMQP for Field→Farm aggregation
Optional Zigbee/Z-Wave for direct sensor integration
HQ / Federated Layer
MQTT or AMQP for data sync
Optional internet-based services for forecasting, optimization, and research integration
4. Notes & Best Practices
AOFS does not mandate a specific protocol; multiple protocols may coexist
Protocol selection should consider latency, reliability, power, and range
Offline-first principle: all safety-critical functions must function without network connectivity
Optional online connections (e.g., for forecasts, research data) must never override safety-critical rules
Protocols should be auditable and loggable to maintain operational traceability