# Channel Names

> Understand the naming criteria and format required for Vivox channels.

When you create a channel name, the following criteria apply:

* Maximum of 200 characters
* Use only the following characters:

| Alphanumerics     | 0-9, A-Z, a-z | 0x30-0x39, 0x41-0x5A, 0x61-0x7A |
| ----------------- | ------------- | ------------------------------- |
| Exclamation mark  | ' ! '         | 0x21                            |
| Open parenthesis  | ' ( '         | 0x28                            |
| Close parenthesis | ' ) '         | 0x29                            |
| Plus              | ' + '         | 0x2B                            |
| Minus             | ' - '         | 0x2D                            |
| Period            | ' . '         | 0x2E                            |
| Equals            | ' = '         | 0x3D                            |
| Underscore        | ' \_ '        | 0x5F                            |
| Tilde             | ' \~ '        | 0x7E                            |
| Percent           | ' % '         | 0x7F                            |

> **Note:**
>
> You can only use the percent sign for URL encoding. Follow the percent sign by two uppercase hex characters.

The recommended best practice is to URL-encode the channel name by using only uppercase hex digit characters. Lowercase characters are allowed in the channel name, but not when used as the hex digit characters.

Channel names must start with a confctl prefix and channel type, followed by your [issuer](./access-token-issuer-unity.md), followed by a period '.'.

For example, if your issuer name is "crux", then a valid channel name is `confctl-g-crux.0verl0rd-channel`

> **Note:**
>
> For the Vivox Unity SDK and the Vivox Unreal SDK, the naming displayed in this example only applies during access token generation. When you construct a ChannelId, you are expected to use only the `"0verl0rd-channel"` part of the channel name and not `"confctl-g-crux.0verl0rd-channel"` for the name argument. The ChannelId function `ToString()` returns a full channel URI that is suitable for token generation, which includes the channel type, issuer, dot, and other URI components.