Create multicast groups to send a downlink payload to multiple devices
To send a downlink payload to multiple devices, create a multicast group. Using multicast, a source can send data to a single multicast address, which is then distributed to an entire group of recipient devices.
Devices in a multicast group share the same multicast address, session keys, and frame counter. By using the same session keys, devices in a multicast group can decrypt the message when a downlink transmission is initiated. A multicast group only supports downlink. It doesn't confirm whether the downlink payload has been received by the devices.
With AWS IoT Core for LoRaWAN's multicast groups, you can:
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Filter your list of devices by using the device profile, RFRegion, or device class, and then add these devices to a multicast group.
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Schedule and send one or more downlink payload messages to devices in a multicast group, within a 48-hour distribution window.
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Have devices temporarily switch to Class B or class C mode at the start of your multicast session for receiving the downlink message.
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Monitor your multicast group setup and the state of its devices, and also troubleshoot any issues.
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Use Firmware Updates-Over-The-Air (FUOTA) to securely deploy firmware updates to devices in a multicast group.
The following video describes how AWS IoT Core for LoRaWAN multicast groups can be created and walks you through the process of adding a device to the group and schedule a downlink message to the group.
The following shows how to create your multicast group and schedule a downlink message.