Channel Configuration

The Channels config options are: Index, Roles, and Settings. Channel config uses an admin message sending a Channel protobuf which also consists of a ChannelSettings or ModuleSettings protobuf.

info

Channel Settings (as described on this page) should not be confused with Modem Preset Settings

Modem Preset Settings contain the modem configuration (frequency settings, spreading factor, bandwidth, etc.) used for the LoRa radio. These settings are identical for all channels and can not be unique per channel.

Channel Settings contain information for segregating message groups, configuring optional encryption, and enabling or disabling messaging over internet gateways. These settings are unique and configurable per channel.

Channel Config Values

Index

The channel index begins at 0 and ends at 7.

Indexing can not be modified.

Index	Channel	Default Role	Purpose
0	1	PRIMARY	Used as default channel
1	2	DISABLED	User defined
2	3	DISABLED	User defined
3	4	DISABLED	User defined
4	5	DISABLED	User defined
5	6	DISABLED	User defined
6	7	DISABLED	User defined
7	8	DISABLED	User defined

note

You can not have DISABLED channels in-between active channels such as PRIMARY and SECONDARY. Active channels must be consecutive.

Role

Each channel is assigned one of 3 roles:

1. PRIMARY or 1
   • This is the first channel that is created for you on initial setup.
   • Only one primary channel can exist and can not be disabled.
   • Periodic broadcasts like position and telemetry are only sent over this channel.
2. SECONDARY or 2
   • Can modify the encryption key (PSK).
3. DISABLED or 0
   • The channel is no longer available for use.
   • The channel settings are set to default.

note

While you can have a different PRIMARY channel and communicate over SECONDARY channels with the same Name & PSK, a hash of the PRIMARY channel's name sets the LoRa frequency slot, which determines the actual frequency you are transmitting on in the band. To ensure devices with different PRIMARY channel name transmit on the same frequency, you must explicitly set the LoRa frequency slot.

Channel Settings Values

The Channel Settings options are: Name, PSK, Downlink Enabled, and Uplink Enabled. Channel settings are embedded in the Channel protobuf as a ChannelSettings protobuf and sent as an admin message.

Name

A short identifier for the channel. (< 12 bytes)

Reserved Name	Purpose
"" (default)	If left empty on the Primary channel, this designates the default channel.
admin	On Secondary channels, the name admin (case sensitive) designates the admin channel used to administer nodes over the mesh

note

Matching channel names are required in order to communicate on the same channel with other devices. Example: If your device is using the channel name LongFast the device you are attempting to communicate with must also have a channel named LongFast.

PSK

The encryption key used for private channels.

Hex byte 0x01 for the Primary default channel.

Must be either 0 bytes (no crypto), 16 bytes (AES128), or 32 bytes (AES256).

note

Matching PSKs are required in order to communicate on the same channel with other devices. Example: If your device is using a channel with the default PSK of AQ== the device you are attempting to communicate with must also have a matching channel with the same PSK.

Downlink Enabled

If enabled, messages captured from a public internet gateway will be forwarded to the local mesh.

Set to false by default for all channels.

Uplink Enabled

If enabled, messages from the mesh will be sent to the public internet through any node's configured gateway.

Set to false by default for all channels.

Channel Module Settings

The channel module settings options are: position precision. Channel module settings are embedded in the Channel protobuf as a ModuleSettings protobuf and sent as an admin message.

Position Precision

The position_precision setting allows control of the level of precision for location data that is sent over a particular channel. This can be useful for privacy reasons, where obfuscating the exact location may be desired when sending position data over certain channels.

The position_precision value is an integer between 0 and 32:

• A value of 0 means that location data is never sent over the given channel.
• A value of 32 means that location data is sent with full precision.
• Values in between indicate the number of bits of precision to be sent.

Some useful values and their approximate precisions:

• 11: Large region, around ±11 kilometers
• 13: City-sized region, around ±3 kilometers
• 16: Neighborhood-level precision, around ±350 meters

The client applications have implemented different levels of precision giving the user a practical range to choose from. Setting across the full range of integers can be done via the Python CLI. See Setting Position Precision for examples on setting different levels of precision using CLI.

Channel Config Client Availability

Android

Android

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Channel Config options are available on Android.

The Radio Configuration tab can be used for common tasks:

1. View your current channel configuration QR code and URL.
2. Quickly create or modify your primary channel.
3. Select a modem preset for all your channels i.e. Long Range / Fast.

See Android App Usage for more further instruction on setting up your primary channel.

Tap the Channel Name (or the pen icon) to access the Channel Menu:

1. Add, remove, or modify secondary channels
2. Create or modify encryption keys
3. Enable uplink and downlink for individual channels
4. Set the position precision value

Apple

Apple

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A channel editor is available on the iOS, iPadOS and macOS applications at Settings > Radio Configuration > Channels.

CLI

CLI

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All Channel config options are available in the python CLI. Example commands are below:

tip

Because the device will reboot after each command is sent via CLI, it is recommended when setting multiple values in a config section that commands be chained together as one.

Example:

meshtastic --ch-set name "My Channel" --ch-set psk random --ch-set uplink_enabled true --ch-index 4

Name

Set channel name for the PRIMARY channel

# without spaces
meshtastic --ch-set name MyChannel --ch-index 0
# with spaces
meshtastic --ch-set name "My Channel" --ch-index 0

PSK

If you use Meshtastic for exchanging messages you don't want other people to see, random is the setting you should use. Selecting default or any of the simple values from the following table will use publicly known encryption keys. They're shipped with Meshtastic source code and thus, anyone can listen to messages encrypted by them. They're great for testing and public channels.

Setting	Behavior
none	Disable Encryption
default	Default Encryption (use the weak encryption key)
random	Generate a secure 256-bit encryption key. Use this setting for private communication.
simple0- simple254	Uses a single byte encoding for encryption

Set encryption to default on PRIMARY channel

meshtastic --ch-set psk default --ch-index 0

Set encryption to random on PRIMARY channel

meshtastic --ch-set psk random --ch-index 0

Set encryption to single byte on PRIMARY channel

meshtastic --ch-set psk simple15 --ch-index 0

Set encryption to your own key on PRIMARY channel

meshtastic --ch-set psk 0x1a1a1a1a2b2b2b2b1a1a1a1a2b2b2b2b1a1a1a1a2b2b2b2b1a1a1a1a2b2b2b2b --ch-index 0

Set encryption to your own key on PRIMARY channel (Base64 encoded)

meshtastic --ch-set psk base64:puavdd7vtYJh8NUVWgxbsoG2u9Sdqc54YvMLs+KNcMA= --ch-index 0

tip

Use this to copy and paste the base64 encoded (single channel) key from the meshtastic --info command. Please don't use the omnibus (all channels) code here, it is not a valid key.

Disable encryption on PRIMARY channel

meshtastic --ch-set psk none --ch-index 0

Uplink / Downlink

For configuring gateways, please see MQTT

Enable/Disable Uplink on PRIMARY channel

meshtastic --ch-set uplink_enabled true --ch-index 0
meshtastic --ch-set uplink_enabled false --ch-index 0

Enable/Disable Downlink on SECONDARY channel

meshtastic --ch-set downlink_enabled true --ch-index 1
meshtastic --ch-set downlink_enabled false --ch-index 5

Setting Position Precision

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This is a per-channel setting. The --ch-index parameter must be specified to set the position precision for a specific channel, e.g., --ch-index 0 for the primary channel or --ch-index 1 for the secondary channel 1.

Set position precision to 13 bits (approx ±3 km)

meshtastic --ch-set module_settings.position_precision 13 --ch-index 0

Set position precision to full precision (32 bits)

meshtastic --ch-set module_settings.position_precision 32 --ch-index 1

Web

Web

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All Channel config options are available in the Web UI.