Meshtastic Protocol Overview

Meshtastic is an open-source mesh networking project built on LoRa radio hardware. It has a large, active global community and is one of the most widely deployed LoRa mesh platforms available.

How Meshtastic routes messages

Meshtastic uses a flooding approach to message delivery. When a node sends a message, nearby nodes rebroadcast it, and those nodes rebroadcast to others, until the message has propagated through the reachable network. A hop limit controls how many times a message can be relayed.

This approach is simple and reliable for small networks. On larger, denser networks, the rebroadcast traffic can create congestion. Meshtastic has introduced optimizations over time (such as managed flooding) to reduce unnecessary retransmissions.

Node roles

Meshtastic devices can be assigned different roles that control how they participate in the network:

• Client —— standard personal device paired with a phone via Bluetooth
• Client Mute —— receives but does not retransmit (reduces traffic in dense areas)
• Router —— optimized for relaying; reduces sleep time, prioritizes forwarding
• Router Client —— acts as both a router and a personal device
• Repeater —— dedicated relay node, does not appear in node lists
• Tracker —— broadcasts GPS position frequently
• Sensor —— designed for environmental sensor data reporting

Channels and encryption

Meshtastic uses a channel-based system. Each channel has a name and a pre-shared key. Devices on the same channel with the same key can communicate. The default public channel uses a well-known key, making messages readable by any Meshtastic node —— it is not private. Private channels use custom keys shared only among trusted users.

Technical specifications

Parameter	Value
Frequency (US/Canada)	915 MHz ISM band (license-free)
Modulation	LoRa (Long Range)
Default channel encryption	AES-256 (with shared key)
Routing	Managed flooding with hop limit
GPS support	Optional (device-dependent)
Protocol	Open source, Protobuf-based