What is MeshCore?
MeshCore is an open-source, decentralized communications platform that uses LoRa (Long Range) radio technology to create resilient, off-grid messaging networks without relying on cellular service, Wi-Fi, or the Internet.
How it works
Each device on the network — called a node — contains a low-power LoRa radio transceiver that broadcasts and receives messages over license-free sub-GHz frequencies (typically 915 MHz in North America and 868 MHz in Europe). Because LoRa uses a spread-spectrum chirp modulation technique, signals can travel several kilometres in open terrain and penetrate obstacles that defeat conventional Wi-Fi or cellular signals, all while drawing only a few milliamps of current.
Messages are routed using a store-and-forward mesh approach: when a packet cannot reach its destination directly, intermediate nodes receive it, hold it briefly, and rebroadcast it toward the intended recipient. This means coverage expands organically as more nodes are added — there is no central server that can fail or be shut down.
All messages are end-to-end encrypted using public-key cryptography. Private messages are readable only by the intended recipient; channel (broadcast) messages are encrypted with a shared channel key. Node identities are derived from cryptographic key pairs rather than assigned by any authority, so the network has no single point of trust.
Key features
- No grid infrastructure required — works entirely over radio; no Internet connection needed
- Long range — typical node-to-node links of 3–15 km; repeaters on high ground can cover 30 km or more
- Low power — portable nodes run for days on a small battery; solar-powered repeaters can operate indefinitely
- Encrypted by default — all traffic is encrypted; private messages use per-contact keys
- Open hardware and firmware — runs on widely available ESP32 + LoRa development boards costing as little as $20
- Cross-platform companion apps — iOS, Android, and desktop clients connect to a node over Bluetooth or USB serial
Common uses
MeshCore is used for emergency and disaster communications, community off-grid networking, outdoor recreation and hiking groups, remote site monitoring, and anywhere that existing communications infrastructure is unavailable, unreliable, or untrusted.
How to get on the mesh
To join the HRMesh network, all you need is a MeshCore-compatible device with MeshCore-compatible firmware. Once you have a node, you can connect to the network and start sending messages to other users in the area.
For detailed instructions on building or purchasing a node, see the Companion Nodes and Repeater Nodes pages.