Concept renderThe Matter protocol is an open smart home standard from the Connectivity Standards Alliance. It is an application layer that runs over IP on Wi-Fi, Thread and Ethernet, with Bluetooth LE used for setup. One certified device can work with several ecosystems at once, and each unit proves its origin with a certificate installed at the factory.
Matter promises that one device works with every major smart home controller. For a product team, it adds work in three places: the radio and SDK, the certification path, and a new step on the production line. This guide explains what the Matter protocol is, how a Matter smart home is put together, and what a device maker has to plan for.
This is an engineering summary. Fees, versions and SDK details change, so check the linked pages before you decide. All sources were read on November 12, 2026.
What is the Matter protocol?
The Connectivity Standards Alliance (CSA) describes Matter as an open smart home protocol that uses existing, familiar technologies. It natively supports Wi-Fi, Ethernet and Thread. Bluetooth LE is used for commissioning only, meaning secure onboarding and initial setup (CSA Matter FAQ, as of November 2026).
Matter sits at the top of the stack. The open source SDK splits it into seven layers: application, data model, interaction model, action framing, security, message framing and routing, and IP framing and transport. The lowest layer hands the payload to the IP network (connectedhomeip README, as of November 2026). So Matter does not care which radio carries a packet, as long as it carries IP.
The CSA says Matter supports more than 30 device types across lighting and electrical, climate, cameras and doorbells, and other groups (CSA Matter page, as of November 2026). A device type defines the clusters a product must expose, such as on/off for a plug or temperature for a sensor. Those clusters are the shared data model that lets any controller read and command the device.
Matter over Thread, Wi-Fi or Ethernet: which transport fits?
The CSA FAQ says Thread suits low-power, battery-operated devices and Wi-Fi suits high-bandwidth devices (as of November 2026). The table adds what each one needs in the home. The last two columns are engineering reasoning.
| Transport | Fits | Needs in the home | Radios on the device |
|---|---|---|---|
| Thread | Low-power, battery-operated devices such as sensors, locks and buttons | A Thread border router in the home to reach the Wi-Fi or Ethernet network | 802.15.4 radio, usually with Bluetooth LE for setup |
| Wi-Fi | Mains-powered or high-bandwidth devices such as plugs, cameras and appliances | Only the home router | Wi-Fi radio; Bluetooth LE for setup unless Wi-Fi-only commissioning is used |
| Ethernet | Fixed devices such as hubs, bridges and controllers | A wired port | Ethernet PHY; setup over the IP network |
Matter over Thread needs a Thread border router. Silicon Labs describes it as a device that connects a Thread network to other IP networks such as Wi-Fi or Ethernet. It is transparent to the protocols above the network layer, so no application-layer translation is needed (Silicon Labs Thread fundamentals, as of November 2026). Your product cannot assume the user already owns one, so say on the box that it needs one.
Bluetooth LE setup is changing. Matter 1.4.2 added Wi-Fi-only commissioning through Wi-Fi Unsynchronized Service Discovery, so a Wi-Fi device can be onboarded without a Bluetooth LE radio (CSA Matter 1.4.2 announcement, as of November 2026). Check that the controllers your users own support it before you drop Bluetooth from the BOM. For how Thread compares with Zigbee on the same radio, see Zigbee vs Thread vs Matter. For the Bluetooth side, see what Bluetooth Low Energy is.
How does a Matter smart home work with several controllers?
A controller is the app or hub that adds and runs devices. The CSA says users can choose which platforms access their Matter devices with the multi-admin feature (CSA Matter FAQ, as of November 2026). Each platform is its own fabric, and one device can belong to several fabrics.
Commissioning and security
Silicon Labs' Matter security guide explains the steps (Silicon Labs Matter security, as of November 2026):
- Setup starts with PASE, Password Authenticated Session Establishment, using the passcode from the device's QR code.
- The controller checks the device's attestation certificate before the device joins the Thread or Wi-Fi network.
- The device then gets a Node Operational Certificate (NOC), which identifies it within a fabric.
- Normal operation uses CASE, Certificate Authenticated Session Establishment, between controller and device.
Matter also includes specifications for bridges, which expose non-Matter devices to Matter controllers (CSA Matter FAQ, as of November 2026). A bridge is one way for an existing Zigbee product to reach a Matter controller.
Recent versions
The CSA announced Matter 1.5 on November 20, 2025. It added cameras that stream live video and audio over WebRTC, closures such as shades and garage doors, soil sensors, energy management features, and full support for operation over TCP for large transfers such as firmware updates. The CSA said the 1.5 specification, SDK and test tools were available to Alliance members (CSA Matter 1.5 announcement, as of November 2026). Pick the version your product certifies against early, since device types and clusters differ between releases.
What does Matter certification require?
The CSA certification page lists three phases: product development, testing at an Authorized Test Provider, and an application to the Alliance. Certification is available to CSA members only, and every new product certification needs testing at an authorized provider. The primary costs are the testing fee and the application fee. A certified Matter product receives a Certification Declaration (CD) file and a record in the Distributed Compliance Ledger (DCL) (CSA certification page, as of November 2026).
The CSA membership page lists these fees. Testing fees are quoted separately by each test provider.
| Membership level | Annual fee | Develop, test and certify | Certify own derivative product |
|---|---|---|---|
| Adopter | $7,500 per year | $3,000 per product | $2,500 per product |
| Participant | $21,500 per year | $2,000 per product | $1,500 per product |
| Promoter | $112,500 per year | $2,000 per product | $1,500 per product |
Source: CSA membership page, as of November 2026. The Promoter level also has a one-time initiation fee. An Associate level with no membership fee lets a company rebrand a product certified by a Participant or Promoter partner through the Certification Transfer Program, for a per-product fee plus a yearly per-product fee.
The CSA FAQ adds that Matter certification requires devices to be certified for the underlying technologies they use, and that manufacturers must put product data into the DCL (as of November 2026). FCC authorization for the radios is a separate process again.
Device attestation: the factory step
Every Matter device carries a chain of certificates. Silicon Labs explains the pieces (Silicon Labs Matter device attestation, as of November 2026):
- The Product Attestation Authority (PAA) is a root certificate. PAAs are kept in the DCL and are not stored on devices.
- The Product Attestation Intermediate (PAI) is signed by the PAA and stored on the device.
- The Device Attestation Certificate (DAC) uniquely identifies one device and is signed by the PAI.
- The CD is a file issued by the CSA.
- DACs are immutable, so they must be installed in the factory.
So the production line gains a provisioning station that gives each unit a unique DAC. Silicon Labs describes two ways. In the preferred one, the device generates its own key pair and requests the DAC. In the other, the key and DAC are generated off the device and written to it, and the key must stay secret on the way in (Silicon Labs, as of November 2026). Plan the certificate source, the key handling and the station before the pilot build. For how the device, app and cloud split the rest of the system, see IoT architecture for a connected device.
Which SDKs and chips can you build a Matter device on?
The reference is the open source Matter SDK, connectedhomeip, released under Apache 2.0 (connectedhomeip, as of November 2026). Chip vendors wrap it with their own tools:
- Espressif's SDK for Matter is built on the open source SDK. Espressif lists its ESP32, ESP32-C and ESP32-S series for Matter Wi-Fi devices and the ESP32-H series, ESP32-C5 and ESP32-C6 for Matter Thread devices. It also describes a Thread border router built from an ESP32-H and a Wi-Fi SoC (ESP Matter programming guide, as of November 2026).
- Silicon Labs publishes its own Matter documentation and tools, at version 2.9.2 on the attestation page read for this guide (Silicon Labs, as of November 2026). Its documentation also covers a provisioning tool and test certificates for development (Silicon Labs Matter provisioning, as of November 2026).
Each vendor SDK pins a Matter release. Ask which one, and how fast the vendor moves to the next. For the chips and radios we design with, see platforms we design with.
What should you ask your hardware team?
Bring this list to the platform review, before the radio and SDK are fixed.
- Which transport does each product use (Thread, Wi-Fi or Ethernet), and why?
- Which Matter version and which SDK release is the firmware built on, and who tracks new releases?
- Which device type does the product claim, and does every cluster it needs exist in that version?
- Who holds the CSA membership, the vendor ID and the product IDs?
- Where do the DACs come from, and how are they written to each unit on the production line?
- How is the DAC private key protected on the device and during factory provisioning?
- Which controllers will we test with before the lab, and on which phones?
- How do OTA updates reach the device, and who signs the images?
Questions about the Matter protocol
Is Matter a radio like Wi-Fi or Zigbee?
No. Matter is an application layer. The CSA says it natively supports Wi-Fi, Ethernet and Thread, and uses Bluetooth LE only for commissioning (Matter FAQ, as of November 2026). The radio choice is a separate decision. See Zigbee vs Thread vs Matter.
Can an existing smart home device be updated to Matter?
Sometimes. The CSA says many existing products can be updated through software, and that it depends on the device's technical capabilities (Matter FAQ, as of November 2026). The radio, flash size and the ability to store a unique attestation certificate usually decide it.
Is the Matter SDK free to use?
The open source Matter SDK on GitHub is released under the Apache 2.0 license (connectedhomeip, as of November 2026). Selling a certified product is a separate step that needs CSA membership and certification fees.
How much does Matter certification cost?
The CSA lists an annual membership fee plus a per-product certification fee. At the Adopter level, the CSA lists $7,500 per year and $3,000 per product. Testing fees are quoted by each authorized test provider (CSA membership page, CSA certification page, as of November 2026). Radio and FCC testing are separate costs.
How can Duobay help with a Matter device?
Duobay develops custom devices with a Shenzhen engineering team: electronics, firmware, enclosure and, as an option, the phone app, plus samples and small batches. The transport choice, SDK setup and factory provisioning plan are part of that work. Firmware source and the SBOM are delivered to you, and source files are assigned to you at every paid gate. We do not publish prices, and initial calls are free. Tell us about your device.
If you want a transport choice, an SDK plan and a factory provisioning plan for a Matter product, tell us about your device.
Sources. All pages accessed November 12, 2026. Fees, versions and SDKs change, so confirm current values before you decide.
- Connectivity Standards Alliance, Matter (link)
- Connectivity Standards Alliance, Matter FAQs (link)
- Connectivity Standards Alliance, Certification process (link)
- Connectivity Standards Alliance, Become a member (link)
- Connectivity Standards Alliance, Matter 1.4.2 announcement (link)
- Connectivity Standards Alliance, Matter 1.5 announcement, November 20, 2025 (link)
- Project CHIP, connectedhomeip repository README (link)
- Silicon Labs, Matter Device Attestation, Matter 2.9.2 (link)
- Silicon Labs, Matter Provisioning, Matter 2.9.2 (link)
- Silicon Labs, Matter Security (link)
- Silicon Labs, Thread Fundamentals, Border Router (link)
- Espressif, ESP Matter programming guide, Introduction (link)
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