Creating Private Channels
To communicate privately with a group, create a channel with a unique PSK known only to group members. Anyone without the PSK cannot decrypt messages on that channel.channel - unless a gateway on that channel uplinks to MQTT without encryption_enabled, which republishes the traffic in cleartext to the broker. Channels are encrypted with AES-256-CTR when you use a full 32-byte (256-bit) PSK (a 16-byte key gives AES-128).
Via the App
- Open the Meshtastic app and go to Radio Config → Channels
- Select an unused channel slot (index 1 - 7; leave index 0 as the public primary unless you have a specific reason to change it)
- Set a channel name (e.g.,
TeamAlpha) - Tap Generate to create a random PSK, or enter a known PSK manually
- Save the channel
- Share the channel URL or QR code with group members out-of-band (signal, in person, etc.)
Via the CLI
Add a new channel (this creates an empty channel at indexthe 1:next free index; do not pass the name to --ch-add):
meshtastic --ch-add TeamAlpha
SetName the channel'schannel and set its PSK (replaceon withthat index. Use random to have the firmware generate a strong key, or supply your actualown key)base64 key string directly (there is no base64: prefix):
meshtastic --ch-index 1 --ch-set name TeamAlpha
meshtastic --ch-index 1 --ch-set psk base64:YOUR_BASE64_KEY_HERErandom
Export the channel URL for sharing:
meshtastic --export-config
The config export includes channel URLs that can be shared with other users.
Security Considerations
- PSK distribution security: The security of a private channel is entirely dependent on how the PSK is distributed. Share it via an end-to-end encrypted channel (Signal, in person) - not via SMS or unencrypted email.
- The default LongFast channel is not private. All Meshtastic users can read it. Never send sensitive information on LongFast.
- MQTT uplink can leak even a private channel. If any gateway node on your private channel uplinks to an MQTT broker without
mqtt.encryption_enabledset, your channel's traffic is republished to the broker in cleartext - so "no PSK = can't read it" only holds for the RF mesh, not for an MQTT-connected mesh.
Position and Telemetry Privacy
By default, position and telemetry are broadcast on channel 0 (the public primary channel). If you want location data to remain within your private group:
MoveThethesimplest,primarylowest-riskchanneloption is toyour private channel (swap index 0)