# Manage connections (/en/realtime-media/iot/build/manage-connections-and-quality/connection-management)

> For AI agents: see the complete documentation index at [llms.txt](/llms.txt).

IoT SDK identifies each RTC connection with a connection ID (`connection_id_t`). You create a connection before joining a channel, use the connection ID to scope every subsequent call (join, send data, mute, leave) to that connection, and destroy the connection when you are done with it. This mechanism lets a single device manage multiple independent connections at once, for example to [stream to multiple channels or push multiple streams to a single channel](multi-channel-streaming.mdx).

This page shows you how to create, inspect, and destroy connections in your IoT SDK app.

## Prerequisites

In order to follow this procedure you must have:

* Implemented the basic IoT SDK functionality. See [Build from scratch](../../build-from-scratch.mdx).

## Create a connection

Call `agora_rtc_create_connection` after you initialize the engine and before you join a channel:

```c
// Create a connection
rval = agora_rtc_create_connection(&g_conn_id);
if (rval < 0) {
    printf("Failed to create connection, reason: %s\n", agora_rtc_err_2_str(rval));
    return -1;
}
```

Use `g_conn_id` in every subsequent call that is scoped to this connection, such as `agora_rtc_join_channel`, `agora_rtc_send_audio_data`, `agora_rtc_send_video_data`, `agora_rtc_mute_local_audio`, and `agora_rtc_leave_channel`.

## Inspect connection info

Call `agora_rtc_get_connection_info` to retrieve details about an active connection, such as the channel it is joined to. This example logs the channel name when the connection successfully joins a channel:

```c
static void __on_join_channel_success(connection_id_t conn_id, uint32_t uid, int elapsed) {
    g_connected_flag = true;
    connection_info_t conn_info = {0};
    agora_rtc_get_connection_info(g_conn_id, &conn_info);
    printf("[conn-%u] Join the channel %s successfully, uid %u elapsed %d ms\n", conn_id, conn_info.channel_name, uid, elapsed);
}
```

## Destroy a connection

When you are done with a connection, typically when the app shuts down or leaves a channel for good, leave the channel and then destroy the connection to release its resources:

```c
agora_rtc_leave_channel(g_conn_id);
agora_rtc_destroy_connection(g_conn_id);
agora_rtc_fini();
```

## Reference

### API reference

* [agora\_rtc\_create\_connection](https://api-ref.agora.io/en/iot-sdk/linux/1.x/agora__rtc__api_8h.html)
* [agora\_rtc\_get\_connection\_info](https://api-ref.agora.io/en/iot-sdk/linux/1.x/agora__rtc__api_8h.html)
* [agora\_rtc\_destroy\_connection](https://api-ref.agora.io/en/iot-sdk/linux/1.x/agora__rtc__api_8h.html)