MOSH (Modern Offline Smart Home) is a lightweight, transport-agnostic messaging protocol designed for embedded systems and distributed smart-home environments.

The protocol is optimized for:

• Small microcontrollers (e.g., ATmega128)
• Deterministic parsing
• Minimal memory usage
• Transport independence (nRF24, ESP-NOW, UART, etc.)
• Decentralized operation (no required central coordinator)

MOSH separates responsibilities into:

• Core System
  • Element Manager
  • Message Router
  • Node Manager
  • State Manager
  • System Services
  • Transport Manager
  • Trust Manager
  • Virtual Wire Manager

• Transport Layer
  • Addressing
  • Duplicate Detection
  • Framing
  • Fragmentation
  • Medium Adapter
  • Reliability
  • TTL/Hop Handling

• Platform Hardware Abstraction Layer (HAL)
  • Logging
  • Random/Entropy
  • Time
  • Transport Drivers