I came across Meshtastic while looking into LoRa hardware for off-grid communication — the use case I had in mind was emergency messaging without cellular, which APRS has done since the 1980s but with significant constraints around authentication and privacy. I ended up running both: a T-Beam on Meshtastic for encrypted local mesh and an APRS setup on 144.390 MHz for position beaconing and digipeater integration. The two protocols solve different problems and the security models are almost opposite, which makes them worth understanding side by side.
Overview
Two decentralized communication protocols for emergency and off-grid messaging: APRS (amateur radio, 1980s) and Meshtastic (LoRa, 2020s). Both operate without cellular infrastructure.
APRS (Automatic Packet Reporting System)
- Frequency: 144.390 MHz (North America)
- Modulation: 1200 baud AFSK on AX.25
- Network: digipeaters relay packets, APRS-IS bridges to internet
- Uses: position tracking, weather stations, messaging, telemetry
APRS services (bots)
- SMSGTE — send SMS via APRS message
- WXBOT — weather reports
- WLNK-1 — Winlink email gateway
- EMAIL — direct email gateway
Security gaps
- No authentication — open network, anyone can inject packets
- No encryption — all traffic is plaintext (FCC requirement for amateur radio)
- Position tracking — beaconing reveals location by design
Meshtastic
- Protocol: LoRa on 906.875 MHz (US) ISM band
- Encryption: AES-256 with pre-shared keys, channel-based key exchange
- Range: 1-10+ km depending on terrain and antenna
- Mesh routing: automatic multi-hop, no infrastructure needed
Hardware platforms
| Chipset | Features | Devices |
|---|---|---|
| nRF52840 | Low power, BLE only | Techo, WisBlock, T1000E |
| ESP32 | WiFi + BLE, more storage | T-Beam, T-Deck, Heltec V3 |
| RP2040 | Flexible, USB host | Custom builds |
Vendors
LilyGo (T-Beam, T-Deck), RAK Wireless (WisBlock), Heltec, Seeed Studio
Security comparison
| Property | APRS | Meshtastic |
|---|---|---|
| Encryption | None (illegal on ham) | AES-256 PSK |
| Authentication | None | Channel key |
| Privacy | No (position broadcast) | Optional (encrypted) |
| DoS resistance | Low (open network) | Medium (rate limiting) |
| Infrastructure | Digipeaters + APRS-IS | Zero (peer mesh) |
Bridging
- APRS-IS — internet gateway for APRS
- Meshtastic MQTT — bridge Meshtastic mesh to internet
- APRS over LoRa — experimental bridge at 433 MHz
Community
- Maps: aprs.fi, meshmap.net
- Nets: #APRSThursday, WinlinkWednesday
The T-Beam running Meshtastic is currently the primary off-grid messaging node, paired with APRS for situations where internet-bridged position visibility matters — search and rescue coordination, for instance, where APRS-IS integration means others can track position without being on the local mesh. Note that the two systems do not interoperate natively; the APRS-over-LoRa bridge is experimental and not reliable enough for anything that needs to actually work.
See also
- Amateur Radio — RF fundamentals and digital modes
- IoT and Hardware — LoRa hardware hacking