Hardware Reference Designs

Mehr is designed to run on hardware ranging from $30 solar-powered relays to GPU workstations. Every device participates at whatever level its hardware allows.

Device Tiers Overview

Tier	Hardware	Cost	Power	Primary Role
Minimal	ESP32 + LoRa SX1276	~$30	0.5W (solar)	Relay only
Community	Pi Zero 2 W + LoRa HAT + WiFi	~$100	3W	LoRa/WiFi bridge, basic compute
Gateway	Pi 4/5 + LoRa + cellular modem + SSD	~$300	10W	Internet uplink, storage, compute
Backbone	Mini PC + directional WiFi + fiber	~$500+	25W+	High-bandwidth backbone
Inference	x86 + GPU + Ethernet	~$500+	100W+	Heavy compute, ML inference

Minimal Relay Node

Target: Lowest-cost, always-on mesh relay

Components:
  - ESP32-S3 microcontroller
  - LoRa SX1276/SX1262 radio module
  - Small solar panel (2W) + LiPo battery
  - Weatherproof enclosure

Capabilities:
  - Packet relay only
  - MHR-Byte interpreter (~50 KB)
  - No storage beyond routing tables
  - 24/7 operation on solar power

Software:
  - Mehr firmware (Rust, no_std)
  - Transport: LoRa only
  - Runs: routing, payment channels, gossip
  - Cannot run: WASM, storage, heavy compute

Earns from: Routing fees (1-5 μMHR per packet relayed)

Range: 2-15 km line-of-sight with LoRa

Community Bridge Node

Target: Bridge between LoRa mesh and local WiFi network

Components:
  - Raspberry Pi Zero 2 W
  - LoRa HAT (SX1262)
  - Built-in WiFi
  - SD card (32 GB)
  - USB power supply (5V/2A)

Capabilities:
  - LoRa ↔ WiFi bridging
  - Basic MHR-Compute (MHR-Byte + light WASM)
  - Local storage (~16 GB usable)
  - MHR-DHT participation
  - Message caching for offline nodes

Software:
  - Mehr daemon (Rust, Linux)
  - Dual transport: LoRa + WiFi
  - Full protocol stack

Earns from: Bridging fees, compute delegation, storage

Gateway Node

Target: Internet uplink for the mesh

Components:
  - Raspberry Pi 4/5 (4 GB+ RAM)
  - LoRa HAT
  - 4G/LTE cellular modem (or Ethernet)
  - SSD (256 GB+)
  - Powered supply (12V)

Capabilities:
  - Internet gateway (HTTP proxy, DNS relay)
  - Full MHR-Store storage node
  - MHR-DHT backbone participation
  - Full WASM compute
  - Epoch consensus participation

Software:
  - Full Mehr stack
  - Triple transport: LoRa + WiFi + Cellular/Ethernet
  - Gateway proxy services

Earns from: Internet gateway fees, storage fees, compute fees, routing

Backbone Node

Target: High-bandwidth infrastructure linking mesh segments

Components:
  - Mini PC (Intel NUC or equivalent)
  - Directional WiFi antenna (point-to-point)
  - Fiber connection (where available)
  - SSD (1 TB+)
  - UPS/battery backup

Capabilities:
  - High-throughput routing (100+ Mbps)
  - Large-scale storage
  - Full compute services
  - Neighborhood discovery services
  - Epoch consensus coordination

Software:
  - Full Mehr stack, optimized for throughput
  - Transport: Directional WiFi + Fiber + Ethernet

Earns from: Bulk routing fees, backbone transit, storage

Inference Node

Target: Heavy compute (ML inference, transcription, TTS)

Components:
  - x86 PC or server
  - GPU (NVIDIA RTX series or equivalent)
  - Ethernet connection
  - SSD (512 GB+)
  - Standard power supply

Capabilities:
  - ML model inference (Whisper, LLaMA, Stable Diffusion, etc.)
  - Speech-to-text, text-to-speech
  - Translation services
  - Any GPU-accelerated computation

Software:
  - Full Mehr stack
  - WASM runtime + native GPU compute
  - Model serving framework
  - Advertises offered_functions with pricing

Earns from: Compute fees for ML inference and heavy processing