The Matter Smart Home Standard

The smart home community was stirred into a frenzy during January of 2020 when it was announced that all the big names in the industry had joined forces under a new initiate to ‘solve’ smart home fragmentation, called the Connected Home over IP initiative.

This initiative was formed under the umbrella of the ZigBee Alliance, probably because most of the players involved were already members. But that has now changed, with the group moving to a new phase as we get closer to what is hoped to be the holy grail of smart home integration, a unifying standard for all devices to communicate.

As a reflection of how significant this is, the ZigBee Alliance is no more, having rebranded to the Connectivity Standards Alliance in 2021. Along with that rebranding came the announcement of Matter, the name chosen for this new connectivity standard. After some delays due to ongoing negotiations on the technical details between members, the Matter Specification 1.0 was finally released in September of 2022 along with a raft of device announcements from dozens of brands.

Personally, I can see that name being a bit of an issue as it’s a common word that has nothing to do with the tech industry, so it’s not easy to find info on it. Nonetheless it shows a lot of promise in delivering on the stated goals.

What is Matter?

Matter is a new integration standard being built by a consortium of major tech brands, including Google, Amazon, Apple, Signify (Philips Hue), Tuya, LeGrand, SmartThings, Huawei, and many more. Importantly, it’s being developed as open source, and we can already dig into the code that has been submitted on GitHub.

The Project’s design and technical processes are intended to be open and transparent to the general public, including to Work Group non-members wherever possible. The availability of this GitHub repository and its source code under an Apache v2 license is an important and demonstrable step to achieving this commitment.
— Connectivity Standards Alliance

Matter provides for the creation of ‘Fabrics’ which are collections of devices that share a common trusted security root. You can have multiple fabrics on the same physical networks, including the same devices, but with difference administrators - administrator is the highest access level in a fabric. This allows for using multiple smart home platforms or apps to control the same set of devices without them needing to share security information.

The Matter specification is available for free download and provides all the required information to implement the standard and is intended for those creating devices or applications that use it. It’s pretty deep, so it won’t be for everyone, and it’s certainly a lot more than you need to understand as a smart home enthusiast.

I’ve distilled the important stuff that you need to understand in this article, and we’ll get into that in a moment.

Why Is Matter important?

Smart Home products need to communicate with each other in order to provide the benefits of automation in the home. Not that long ago every device had its own app, and nothing worked together very well. The big tech players have tried to improve this with their respective platforms by providing a consistent standard that device makers can use to integrate with them, but these are all different, and use different approaches.

Additionally, there are different communication protocols being used, also in an attempt to improve interoperability. These mean that some devices simply aren’t even on the same wavelength (so to speak) as others, so they can’t talk to each other at all.

Sticking to one platform can help to solve the mess of apps and provide a common integration experience, but that doesn’t solve the need for various hubs to enable communication in the first place, nor does it prevent you being shut out of certain products because they don’t support your platform of choice.

Matter aims to solve all these problems by defining a standard communication technology, and a standard application layer that all devices can use and understand consistently. This would eliminate the need for hubs or controllers and allow for devices to be controlled locally, improving reliability and security by negating the need for cloud servers.

Having this standard be based on open-source code, and supported by such a huge swath of the industry is a very good start. That ensures no one needs to be locked out by licensing fees, while still allowing for a widely accepted certification process to ensure standards compliance.

The state of play

Integration Types

Integration Types

Smart device makers and the platforms the integrate with take different approaches to how they, and we, control their devices. Many opt for maximum compatibility and go with the ubiquitous Wi-Fi protocol for communications. That’s fine, but it’s not suitable for smaller battery powered devices like sensors, it can be clunky to set up new devices, and there is no standard for how those devices should communicate with one another.

To solve this last problem, these devices tend to use cloud-based services to control them and provide an application layer interface (API) for others to use. These Web-based APIs are all different and require custom code to interface with them. Platforms like Amazon and Google have adopted this as the primary method of integrating with their platforms. Using a special software plugin built to their own standard, the platform can be told what functions it can use and how to connect to the API.

Of course, this requires every device brand to have a user account, which means more passwords and more risk of leaks and hacks by connecting to a plethora of cloud services with unknown security controls. Oh, and if your internet, or their servers, go down, you can’t use your device at all.

Other makers go with local control provided by specialist smart device protocols like ZigBee and Z-Wave. But these devices need a compatible hub to connect to, and even though these protocols are intended to provide interoperability, variations in implementation means bespoke handlers are still often required to make a device work correctly. This adds complexity and roadblocks for end users.

How Does Matter Work?

The Technology Stack

All modern data networks comprise a ‘stack’ of technologies, each adding functionality on top of one another in layers. Each layer abstracts the ones below and focuses on specific functionality that allows different aspect of the network to function without having to worry about the others. Matter is a stack as well that handles the definition of devices types, data structures, interactions between devices, encryption and authentication of messages, and the packaging of those messages for sending out on the network.

Matter Network Stack

Matter Network Stack

Matter itself sits at the top of the network stack, forming the Application layer. This is where the user-facing logic takes place, in this case controlling our smart devices and getting data back from them. A unified application layer ensure that all devices can understand each other, can read the data they need (say a fan getting data from a temperature sensor), can send commands (a motion sensor telling a light to turn on), and can be accessed by any compatible app (Google Home for example).

This application layer is useless without consistent communication between devices, though. So the standard will specify the communication technologies to be used. Initially this will be Wi-Fi (for high bandwidth) and Thread (for low bandwidth/low power) for operational use, and Bluetooth for initial discovery and provisioning. This is a common use of Bluetooth in the smart device market now, and many device makers use this to simplify locating and pairing with a new device already.

All Matter devices will leverage IP addressing, specifically IPv6. IP is ubiquitous on the internet and throughout the world’s local networks and has proven itself scalable and versatile for all use cases. IPv6 in particular allows for a wide range of addressing and routing schemes that can be universally handled across different network types and has been specifically adopted in the Thread protocol for these reasons. By using IPv6 connected device networks will be able to scale freely and communicate without the risk of being segregated by different intermediate technologies.

As with other standards in the market, device makers will need to seek certification in order to be able to label their products as Matter compatible. We don’t know if any stricter enforcement will be applied yet at the network level. Certification will be performed by the Connectivity Standards Alliance in the same way that ZigBee implementation is certified today.

In Summary

The Matter standard holds the promise is unifying the smart home space and enabling faster, more reliable, and more secure device integration that many devices offer today. More importantly, it will open up the market by enabling the use of any device with any app or platform.

Being open source will greatly help adoption and industry confidence as it ensures many eyes will be on the code base to drive improvements. Having a more open standard will also allow for greater expert knowledge to grow in the community as the technical details won’t be walled off by expensive fees or “black box” implementations.

I’ll be updating this article as we learn more about the standard and the implementation details.