# allowed\_connection\_types

Hot Reloadable

If specified, the user is constrained to the specified connection types.

* `STANDARD` indicates a standard client TCP connection using the NATS protocol.
* `WEBSOCKET` indicates a WebSocket-based connection to NATS if the `websockets` configuration is enabled.
* `LEAFNODE` indicates a connection established by configured leafnode `remote` on a server.
* `MQTT` indicates a connection established by an MQTT client to NATS if the `mqtt` configuration is enabled.

## Types

| Type         | Description | Choices                                     |
| ------------ | ----------- | ------------------------------------------- |
| `[ string ]` | -           | `STANDARD`, `WEBSOCKET`, `LEAFNODE`, `MQTT` |