Overview of OTA

Each Matter integration in the Google Home Developer Console has its own over-the-air (OTA) configuration.

The Matter specification describes how OTA updates are handled by the global Matter network.

A Matter device must be Connectivity Standards Alliance (Alliance)-certified to receive OTA updates, although it is possible to test OTA for an uncertified device.

A Matter device (the OTA Requestor), periodically polls an OTA Provider to find out whether there are any available software updates.

When an OTA software update is available, the Requestor obtains the update from a Provider and installs it.

Google Matter hubs, such as the Google Nest Mini, function as OTA Providers. To assist potential Requesters in service discovery, they announce their presence by sending the AnnounceOTAProvider command.

Importantly, a Requester may only upgrade to an update whose version number is numerically greater than that of the firmware it is currently running. And if multiple OTA updates with larger version numbers exist, the device receives the OTA image with the highest version number. In other words, updates are not applied sequentially.

OTA Functionality

OTA in the Google Home ecosystem currently supports:

  • Uploading firmware for OTA distribution
  • Distribution of firmware images to all devices (no subsets) of a particular Matter integration

The Google Home ecosystem OTA process is independent from the information stored on the Alliance Distributed Compliance Ledger (DCL), whose purpose is to ensure device authenticity and protocol compliance.

Can I roll back an OTA update?

Per the Matter specification, OTA images cannot be rolled back. If you have released an OTA image that has an issue, and you want to revert your customer's devices to the previous revision of the firmware, you should prepare an OTA update using the previous revision of the firmware, giving it a higher version number.

Can I delete or replace an OTA update?

There is no way to delete or replace an OTA update. You must prepare and upload an OTA image with a higher version number in order to overwrite the firmware that's out in the field.

Prerequisites

To implement OTA for your Matter integration, you need:

  • An existing Developer Console project
  • An existing Matter integration on the Developer Console
  • A valid Alliance-assigned Vendor ID

Note that Matter certification is not a prerequisite for testing Matter OTA on Developer Console—you should test OTA for your device before applying for Matter certification.

Known issues

Inconsistent test-VID OTA controls

When using a test VID, some integrations within the same project may appear in the Developer Console Matter OTA screen, while others don't.

For integrations with a test VID that do appear in the OTA screen, you can upload an OTA image, but the OTA mechanism doesn't function.

OTA is not currently supported for test VIDs.