# Announce Sender

# Announce Sender

This module includes configuration variables for the Announce Sender.

## Summary

| ### Macros ||
|---|---|
| `https://openthread.io/reference/config/group/config-announce-sender#group__config-announce-sender_1ga1752a0547a1415da32028a4df034325b 1` | Define as 1 to enable `AnnounceSender` which will periodically send MLE Announce message on all channels. |
| `https://openthread.io/reference/config/group/config-announce-sender#group__config-announce-sender_1gac7e73ea2ae1a6fb6ab39471e0e75710a 688000` | Specifies the time interval (in milliseconds) between `AnnounceSender` transmit cycles. |
| `https://openthread.io/reference/config/group/config-announce-sender#group__config-announce-sender_1ga99d6efe52b02de04313d7e72b84d2195 500` | Specifies the jitter interval (in milliseconds) used by `AnnounceSender`. |
| `https://openthread.io/reference/config/group/config-announce-sender#group__config-announce-sender_1gadb859c679621ba3a1626f49a9d013ebf 8` | Specifies the number of MLE Announcement messages that the device must receive within a cycle interval to skip sending the Announcement itself. |

## Macros

### OPENTHREAD_CONFIG_ANNOUNCE_SENDER_ENABLE

```
 OPENTHREAD_CONFIG_ANNOUNCE_SENDER_ENABLE 1
```
Define as 1 to enable `AnnounceSender` which will periodically send MLE Announce message on all channels.

The list of channels is determined from the Operational Dataset's ChannelMask.

### OPENTHREAD_CONFIG_ANNOUNCE_SENDER_INTERVAL

```
 OPENTHREAD_CONFIG_ANNOUNCE_SENDER_INTERVAL 688000
```
Specifies the time interval (in milliseconds) between `AnnounceSender` transmit cycles.

In a cycle, the `AnnounceSender` sends MLE Announcement on all channels in Active Operational Dataset's ChannelMask. The transmissions on different channels happen uniformly over the given interval (i.e., if there are 16 channels, there will be 16 MLE Announcement messages each on one channel with `interval / 16` between two consecutive MLE Announcement transmissions).

Applicable only if `AnnounceSender` feature is enabled (see `OPENTHREAD_CONFIG_ANNOUNCE_SENDER_ENABLE`).

### OPENTHREAD_CONFIG_ANNOUNCE_SENDER_JITTER_INTERVAL

```
 OPENTHREAD_CONFIG_ANNOUNCE_SENDER_JITTER_INTERVAL 500
```
Specifies the jitter interval (in milliseconds) used by `AnnounceSender`.

A random jitter interval is applied to the period between any two successive MLE Announcement transmissions (possibly) on different channels.

### OPENTHREAD_CONFIG_ANNOUNCE_SENDER_REDUNDANCY_CONSTANT

```
 OPENTHREAD_CONFIG_ANNOUNCE_SENDER_REDUNDANCY_CONSTANT 8
```
Specifies the number of MLE Announcement messages that the device must receive within a cycle interval to skip sending the Announcement itself.

This is used as the trickle timer redundancy constant in `AnnounceSender`.

Applicable only if `AnnounceSender` feature is enabled (see `OPENTHREAD_CONFIG_ANNOUNCE_SENDER_ENABLE`).

## Resources

OpenThread API Reference topics originate from the source code, available
on [GitHub](https://github.com/openthread/openthread/tree/main/include/openthread).
For more information, or to contribute to our documentation, refer to
[Resources](https://openthread.io/resources).