meshtastic/docs/software/settings/channel.md

---
id: channel
title: Channel Settings
sidebar_label: Channel
---
import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';

## Overview

Channel settings are an integral part of the way your devices communicate across the mesh. If you have mismatched channel settings, your radios will be unable to communicate with one another.

## Settings

<!--- TODO add other channel settings --->

| Setting | Acceptable Values | Default |
| :-----: | :---------------: | :-----: |
| id | `integer` | `0` |
| modem_config | `Bw125Cr45Sf128`, `Bw500Cr45Sf128`, `Bw31_25Cr48Sf512`, `Bw125Cr48Sf4096` | `Bw125Cr45Sf128` |
| name | `string` | `""` |
| psk | `0`, `1`, `2`, `3`, `4`, `5`, `6`, `7`, `8`, `9`, `none`, `default`, `random` | `1` |
| region | `Unset`, `US`, `EU433`, `EU865`, `CN`, `JP`, `ANZ`, `KR`, `TW`, `RU` | `Unset` |

### id

<!--- Used to construct a globally unique channel ID. The full globally unique ID will be: "name.id" where ID is shown as base36. Assuming that the number of meshtastic users is below 20K (true for a long time) the chance of this 64 bit random number colliding with anyone else is super low. And the penalty for collision is low as well, it just means that anyone trying to decrypt channel messages might need to try multiple candidate channels. Any time a non wire compatible change is made to a channel, this field should be regenerated. There are a small number of 'special' globally known (and fairly) insecure standard channels. Those channels do not have a numeric id included in the settings, but instead it is pulled from a table of well known IDs. (see Well Known Channels FIXME) --->

#### Set Channel ID
<Tabs
  groupId="settings"
  defaultValue="cli"
  values={[
    {label: 'CLI', value: 'cli'},
    {label: 'Android', value: 'android'},
    {label: 'iOS', value: 'iOS'},
    {label: 'Web', value: 'web'},
  ]}>
  <TabItem value="cli">

  ```bash title="Set the PRIMARY channel ID"
  meshtastic --ch-set id 1234 --ch-index 0
  ```

  </TabItem>
  <TabItem value="android">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="iOS">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="web">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
</Tabs>

:::note
The channel `id` must be an integer.
:::


### modem_config

| Setting | Name (Range/Speed) | Bandwidth | Coding Rate | Spread Factor | Speed |
| :-----: | :--: | :-------: | :---------: | :-----------: | :-----: |
| `Bw500Cr45Sf128` | Short/Fast | 500 kHz | 4/5 | 7 = 128chips/symbol | 18.89 kbps |
| `Bw125Cr45Sf128` | Short/Slow | 125 kHz | 4/5 | 7 = 128chips/symbol | 4.69 kbps |
| `Bw250Cr47Sf1024` | Medium/Fast | 250 kHz | 4/7 | 10 = 1024chips/symbol | 1.2 kbps |
| `Bw250Cr46Sf2048` | Medium/Slow | 250 kHz | 4/6 | 11 = 2048chips/symbol | 0.75 kbps |
| `Bw31_25Cr48Sf512` | Long/Fast | 31.25 kHz | 4/8 | 9 = 512chips/symbol | 0.19 kbps |
| `Bw125Cr48Sf4096` | Long/Slow | 125 kHz | 4/8 | 12 = 4096chips/symbol | 0.13 kbps |

#### Set Modem
<Tabs
  groupId="settings"
  defaultValue="cli"
  values={[
    {label: 'CLI', value: 'cli'},
    {label: 'Android', value: 'android'},
    {label: 'iOS', value: 'iOS'},
    {label: 'Web', value: 'web'},
  ]}>
  <TabItem value="cli">

  ```bash title="Set Modem - LongSlow"
  meshtastic --ch-set modem_config Bw125Cr48Sf4096 --ch-index 0
  ```
  </TabItem>
  <TabItem value="android">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="iOS">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="web">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
</Tabs>

:::tip
For advanced modem configuration, see [Channel Settings - Advanced](channel-advanced).
:::

### name

The name of the channel. If this is left an empty string it is assumed that this channel is the special (minimally secure) "Default" channel. Channel Names should be short (less than 12 bytes).

#### Set Channel Name
<Tabs
  groupId="settings"
  defaultValue="cli"
  values={[
    {label: 'CLI', value: 'cli'},
    {label: 'Android', value: 'android'},
    {label: 'iOS', value: 'iOS'},
    {label: 'Web', value: 'web'},
  ]}>
  <TabItem value="cli">

  ```bash title="Set channel name for the PRIMARY channel"
  meshtastic --ch-set name MyChannel --ch-index 0
  ```

  ```bash title="Set channel name for the PRIMARY channel with spaces"
  meshtastic --ch-set name "My Channel" --ch-index 0
  ```
  </TabItem>
  <TabItem value="android">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="iOS">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="web">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
</Tabs>

:::note
A channel `id` must be set in order to name a channel.
:::

### psk

:::note
Selecting a `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 |

:::tip
If you use Meshtastic for exchanging messages you don't want other people to see, `random` is the setting you should use.
:::

#### Set/Disable Encryption
<Tabs
  groupId="settings"
  defaultValue="cli"
  values={[
    {label: 'CLI', value: 'cli'},
    {label: 'Android', value: 'android'},
    {label: 'iOS', value: 'iOS'},
    {label: 'Web', value: 'web'},
  ]}>
  <TabItem value="cli">

  ```bash title="Set encryption to default on PRIMARY channel"
  meshtastic --ch-set psk default --ch-index 0
  ```
  ```bash title="Set encryption to random on PRIMARY channel"
  meshtastic --ch-set psk random --ch-index 0
  ```
  ```bash title="Set encryption to single byte  on PRIMARY channel"
  meshtastic --ch-set psk simple15 --ch-index 0
  ```
  ```bash title="Set encryption to your own key on PRIMARY channel"
  meshtastic --ch-set psk 0x1a1a1a1a2b2b2b2b1a1a1a1a2b2b2b2b1a1a1a1a2b2b2b2b1a1a1a1a2b2b2b2b --ch-index 0
  ```
  ```bash title="Disable encryption on PRIMARY channel"
  meshtastic --ch-set psk none --ch-index 0
  ```
  </TabItem>
  <TabItem value="android">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="iOS">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="web">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
</Tabs>

### region

The `region` variable sets which region your radio is configured to work in. It is important to ensure that you've set it to the correct region. If left `Unset`, it will default to `US` settings.

| Name | Center Frequency | Spacing | Number of Channels | Power Limit |
| :--: | :-------: | :-----: | :----------------: | :---------: |
| US | 903.08 | 2.16 | 13 | 0 |
| EU433 | 433.175 | 0.2 | 8 | 0 |
| EU865 | 865.2 | 0.3 | 10 | 0 |
| CN | 470.0 | 2.0 | 20 | 0 |
| JP | 920.0 | 0.5 | 10 | 13 |
| ANZ | 916.0 | 0.5 | 20 | 0 |
| KR | 921.9 | 0.2 | 8 | 0 |
| TW | 923.0 | 0.2 | 10 | 0 |
| RU | 868.9 | 0.2 | 2 | 20 |
| Unset | 903.08 | 2.16 | 13 | 0 |
:::note
For more details about `region` settings, you can see the source code [here](https://github.com/meshtastic/Meshtastic-device/blob/master/src/mesh/RadioInterface.cpp)
:::

#### Set Region
<Tabs
  groupId="settings"
  defaultValue="cli"
  values={[
    {label: 'CLI', value: 'cli'},
    {label: 'Android', value: 'android'},
    {label: 'iOS', value: 'iOS'},
    {label: 'Web', value: 'web'},
  ]}>
  <TabItem value="cli">

  ```bash title="Unset Region"
  meshtastic --set region Unset
  ```
  ```bash title="Set Region"
  meshtastic --set region US
  ```

  </TabItem>
  <TabItem value="android">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="iOS">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
  <TabItem value="web">

:::info
Configuring this setting is not yet available for the selected platform. If this is incorrect please update the documentation for this page.
:::

  </TabItem>
</Tabs>