|
Source: https://blog.csdn.net/espressif/article/details/122691556
Currently, many large IoT ecosystem suppliers such as Amazon, Apple, Google and Samsung have announced their support for Matter. It is foreseeable that in the gradually expanding Matter ecosystem, more manufacturers will launch more and more Matter devices in the future. This will not only accelerate the growth of smart device categories, but also further enable the interconnection between devices and contribute to the joint construction of a richer Matter ecosystem.
At this point, you may have a question: We already have many IoT devices based on Zigbee, Z-Wave, Bluetooth LE Mesh and other protocols at home. Can these non-Matter devices work with Matter devices? The answer is yes.
In this post, we'll talk about the bridging functionality of Matter.
What is the Matter Bridge Device?
Matter bridge devices allow non-Matter devices to join the Matter ecosystem (i.e., Matter Fabric in the figure below), allowing users to control their Matter and non-Matter devices without distinction.
Matter Bridge Device
In the Matter ecosystem, non-Matter devices can act as "bridged device" nodes and complete the mapping between other protocols (such as Zigbee) and the Matter protocol through the bridge device, so as to communicate with the Matter devices in the system.
The Matter-Zigbee bridge device shown below allows two Zigbee bulbs to join the Matter ecosystem:
Matter-Zigbee bridge device
Data Model of Matter Bridge Device
We introduced the data model of Matter in a previous article. Below is an example of the data model of a Matter bridge device.
Matter Bridge Data Model
-
The device type in Endpoint 0 is Bridge. The PartsList field lists all the endpoints of the bridge device, each of which represents a non-Matter device.
-
The Descriptor Cluster on each endpoint provides information about the specific bridged device.
In addition to acting as a protocol "translator", Matter bridge devices can also have Matter native functions: for example, a smart thermostat device can be used as a bridge device to complete the communication between Zigbee and other protocols and the Matter ecosystem, and can also be used as a standard Matter smart thermostat device to send control instructions to the HVAC system through the Matter protocol. Endpoint 1 in the figure below is the smart thermostat, and the other endpoints represent "bridged devices".
Matter bridge device with Matter native functionality
Now, let's go back to the Matter-Zigbee bridge device example mentioned above.
Matter-Zigbee bridge device workflow
The following is the workflow for controlling Zigbee devices on a mobile phone using the Matter protocol:
Step 1: Matter bridge device, as a device type defined in the Matter protocol, needs to first follow the standard Matter network configuration process to join the Matter network (i.e. Matter fabric).
Step 2: This Matter-Zigbee bridge device needs to join the Zigbee network at the same time. Unlike the Matter protocol, the Zigbee protocol does not define a standard network configuration process, but each manufacturer decides how to distribute network keys. (Since Zigbee 3.0, the most common way to join the network is to complete device authentication and join the network through Install Code.)
Step 3: Once the bridge device joins the Zigbee network, it will discover the devices in the Zigbee network by broadcasting the Match Descriptor Request command. The command includes the required profile, In-Clusters (equivalent to the server) and Out-Clusters (equivalent to the client). In this example, after the bridge device joins the Zigbee network, it will broadcast a question like "Who is the light bulb that supports OnOff Cluster?" Accordingly, the Zigbee device that meets the conditions will reply with a Match Descriptor Response and attach its own network address. After that, the bridge device will add a dynamic endpoint for each matching Zigbee device, so that it can join the Matter network as a bridged device.
Step 4: The Matter system will discover these bridge devices through the Operational Discovery mechanism defined in the Matter specification. (For more information about device discovery in the Matter specification, please stay tuned for our upcoming follow-up article.)
Step 5: In this way, the controller in the Matter system can control the light bulbs in the Zigbee network with the help of the bridge device.
Notes:
Note 1: The interaction mode in the second and third steps is mainly determined by the device vendor and the specific protocol, and is not within the scope of the Matter protocol.
Note 2: The bridge device can dynamically add or delete bridged endpoints based on mechanisms such as heartbeats in non-Matter networks.
The above is a typical workflow for a bridge device to connect a Matter network to a Zigbee network. We can also use a similar workflow to add devices from other ecosystems to the Matter network.
| 
提升卡
变色卡
千斤顶
