About this article

• Audience: Integrators and operators deploying Shadow networking and M8 accessories
• Goal: Choose the right uplink and attach Wi‑Fi, CANbus, and I/O relay accessories correctly
• Type: Reference / product

Summary

Shadow edge cameras support two uplinks and a family of M8 accessories.

Priority	Path	Use when
Preferred	LAN over PoE+ (IEEE 802.3at) on the industrial Ethernet port	Production fleets — power + data on one cable
Supported	WLAN via M8 connector + Wi‑Fi adapter	Sites without hardline, or failover when Ethernet drops

M8 also carries I/O relay control and CANbus vehicle telemetry — independent of which uplink you use.

Ports (do not confuse)

Port	Role
Industrial Ethernet (M12-class)	LAN + PoE+ — preferred production path
M8 accessory port	Wi‑Fi adapter, I/O relay controller, CANbus adapter

Ethernet/PoE+ is not the same connector as M8 accessories. Plan cable plant and power budget separately.

Preferred:   PoE+ switch/injector ──Ethernet──► Shadow (power + LAN)
Secondary:   M8 Wi‑Fi adapter ──WLAN──► Shadow (data; power still needs PoE+ or local supply)
Accessories: M8 ──► relay controller · CANbus adapter · Wi‑Fi adapter
                 │
                 └──► Phantom Vision VMS (MQTT / proxy)

Doctrine: LAN preferred, WLAN secondary

1. Deploy with PoE+ LAN whenever possible — stable bandwidth for 4K encode, MQTT, and justified pulls.
2. Add M8 Wi‑Fi for failover or temporary sites — Ethernet remains primary when both are up.
3. Size PoE+ for peak encode + inference; under-powered PoE forces degraded AI and throttled video.
4. Do not starve PoE+ budget when stacking M8 accessories and high-draw peripherals.

Product brief: Shadow Edge Devices.

WLAN via M8 + Wi‑Fi adapter

Item	Detail
Hardware	M8 Wi‑Fi adapter on the Shadow M8 port
Plugin	m8_wifi
Telemetry	{namespace}/{device_id}/telemetry/wifi (RSSI, SSID, failover state)
Intent	Monitor link quality; fail over toward WLAN when Ethernet is unavailable

Use WLAN as secondary or temporary — not as a substitute for PoE+ power delivery. Shadows still need adequate power (PoE+ or approved local supply) for full AI + encode.

I/O relay controller (M8)

Resource	Typical use
Power relays	Door locks, strobes, contact closures
GPIO	Door sensors, triggers, dry contacts
Status LEDs	Local health / mode

Item	Detail
Plugin	m8_controller
Commands	casper/{id}/cmd/relay (live plugin contract)
Events	devices/{id}/events (e.g. door open/close)
Responses	devices/{id}/responses

On stop(), relays return to a safe state. Validate command ingress through the same MQTT ACL / proxy paths as other fleet commands.

CANbus (M8)

Item	Detail
Hardware	M8 CAN adapter
Plugin	m8_can_bus
Host interface	Linux SocketCAN (can0), J1939-class heavy-vehicle telemetry
Telemetry	{namespace}/{device_id}/telemetry/can

Use CANbus for vehicle / fleet context that correlates with vision events — not as a substitute for the uplink doctrine above.

Deploy plugins (high level)

Plugins live under plugins/ and load as sidecars — they must not claim the main camera encode / RF-DETR pipeline.

Plugin	Role
m8_wifi	WLAN link stats + failover signaling
m8_controller	Relays, GPIO, door events
m8_can_bus	CAN / J1939 telemetry

See M8 accessories and Plugin system.

Safety

• Relays can switch significant loads — isolate low-voltage lab loops from production circuits.
• Keep GPIO current within adapter limits; shared ground on test rigs.
• Prefer PoE+ budgets that cover encode + inference + accessories with margin.

Next steps

• Shadow Edge Devices
• M8 accessories (relay · Wi‑Fi · CAN)
• MQTT topics
• Requirements (edge hardware)
• Products overview

Operator depth

Site wiring photos, SSIDs, and live CAN PGN maps stay in private operator handoff (not published).