Sub-GHz Wi‑Fi (802.11ah / HaLow) — farm sensors and IP backhaul (how-to outline)¶
Purpose¶
Structured how-to outline for using 802.11ah (Wi‑Fi HaLow) across a farm for sensor-grade IP links and local backhaul—with explicit assumptions and links to vault sources. This is not a substitute for site survey, regulatory, and vendor manuals.
Concept primer: Wi‑Fi HaLow.
1. Clarify the job¶
| Need | HaLow often fits when… | Often wrong tool when… |
|---|---|---|
| Sparse telemetry (kB/day) | You still want IP on device or MQTT without building many 2.4 GHz hops | Power budget is tiny and range is extreme—consider LoRa/Meshtastic (comparison) |
| IP cameras / moderate throughput | You can place AP + antennas with line of sight or good sub-GHz behavior | You need multi-acre mesh without careful RF design—validate with field test |
| Backhaul to barn | You have Ethernet at one end and HaLow bridge at the other | Starlink alone is easier but different failure mode (connectivity strategy) |
2. Architecture pattern (generic)¶
- Edge router / firewall remains the trust anchor—HaLow is LAN extension, not a bypass of segmentation (
network segmentation). - HaLow AP uplinks via Ethernet to PoE switch or gateway (capture shows AP + bridge pattern).
- Sensors / bridges attach as 802.11ah STAs or via Wi‑Fi → HaLow bridge for legacy 2.4 GHz devices (vendor PoC narrative).
Source (PoC narrative, not universal): how-to 10x reach HaLow Silex-style capture — SSID/PSK, Ethernet to network, WPA3 mentioned for HaLow link.
3. Field steps (operator checklist)¶
| Step | Action | Citation / note |
|---|---|---|
| A | Map power at AP and bridge sites (solar/battery headroom) | Off-grid power — Demory |
| B | Choose band / channel plan for your regulatory domain | Not in vault as legal advice—verify locally |
| C | Cable Ethernet with surge discipline at building entry | Wiring / electrical cluster |
| D | Configure SSIDs; isolate IoT VLAN if available on upstream router | Segmentation page |
| E | Measure RSSI/throughput seasonally (leaf-on, rain) | Same expectation as V10 WAN logging (validation plan) |
4. Sensor traffic profile¶
- Observation-only (temp, tank level via IP MCU): usually fits HaLow if duty cycle and firmware are sane.
- Safety interlocks: prefer wired or proven local link; do not rely on best-effort IP alone (
automation stop rules).