Interoperability is a well-known issue for IoT players. It is made worse by the growing number of connected devices that do not communicate with each other and of gateways that cannot interpret the data from every sensor. The different protocols (EnOcean, Zigbee, Z-Wave, Bluetooth, Wi-Fi…) do not talk to each other, which can create installation and operating difficulties within the same home or building.
What is interoperability?
In practical terms, interoperability refers to systems that are able to adapt and work together with other independent systems, in order to create a network and make data transfer easier.
The concept of interoperability is divided into 3 layers:
The physical layer represents the frequency band (433 MHz, 868 MHz, 2.4 GHz), the type of modulation and the type of encoding.
→ To draw an analogy with the human body, this would be the vocal cords
The transport layer defines packet sizes, error-handling mechanisms and the routing of messages across the network.
→ Speech
The application layer / data model represents the content of the messages and their meaning.
→ The language (French, English, etc.)
In practice:
For full interoperability, it has to be achieved on all 3 layers.
With a common data model, the data format can be kept throughout the whole journey (the message between product A and product B).
However, if the physical layers are different, gateways will have to be added to move from one world to the other.
At NodOn, the goal is full interoperability on all 3 layers so that one product can act on another: using the same frequency band, the same transport layer and the same data model.
With interoperability on all 3 layers, the need for gateways is kept to a minimum.
What about existing protocols?
Today, 3 protocols guarantee full interoperability: Zigbee, Z-Wave and EnOcean.
Each of these 3 protocols offers a standardised physical layer, transport layer and data model.
Take Zigbee 3.0: when a switch tells a light bulb to turn on, it always says it in the same way, so that it is understood in the same way whatever the brand or manufacturer. Zigbee notably uses an 802.15.4 transport layer, which is highly standardised.
Thread is a protocol that is interoperable on layers 1 and 2. Its transport layer is standardised (802.15.4) and IP-based. This makes its transport interoperability attractive, as IP infrastructure is very widely deployed on the market. Thread has no data model.
Bluetooth offers a standard physical layer (2.4 GHz) and a transport layer standardised by the Bluetooth SIG. There is no data model for Bluetooth yet, but one is being developed: Bluetooth Mesh.
Wi-Fi is highly standardised on the physical and transport layers. However, it has no defined data model.
Matter to solve the interoperability problem?
The new Matter protocol aims for full interoperability. Its data model will be fairly similar to Zigbee's. The transport layers will be IP-based.
Its clever twist is to use Bluetooth for all provisioning and commissioning (pairing, onboarding devices onto a network…).
Matter's promise is to simplify the user experience.
Leave a comment
This site is protected by hCaptcha and the hCaptcha Privacy Policy and Terms of Service apply.