Members of the Connectivity Standards Alliance (CSA), the organization behind Matter, have been working on a project to integrate Matter Network Infrastructure Manager (NIM) into OpenWrt. This is a critical move to populate a rare but vital Matter device category, routers and access points, which has seen few commercial products since its inclusion in the spec.
Recent activity in the official Matter (CHIP) GitHub repository shows more work (mainly from Apple) bringing Matter components to the popular open-source router operating system.
What is Matter NIM?
This (NIM) device type, also known as “Home Routers and Access Points” (HRAP), is one of the most important and complex additions to the Matter standard. It effectively turns a network device into the “password and network admin” for the entire smart home. An HRAP-enabled router becomes the single, authoritative source for a home’s network credentials. This new function is designed to solve two of Matter’s biggest challenges.
First, it simplifies setup. As enabled by the recent Matter 1.4.2 update, an HRAP router can securely hand out Wi-Fi credentials to new Matter-over-Wi-Fi devices, eliminating the clunky process where a user’s phone had to ask for the Wi-Fi password.
Also, it unifies Thread networks by acting as the one source of truth for the home’s Thread network. This stops the problem of new Thread border routers (like smart speakers) creating their own separate, competing networks. Instead, they will ask the HRAP router for the existing network credentials and join the single, unified mesh, making it stronger, which is the Matter-wise solution compared with the native Thread Credential Sharing in Thread 1.4. This means future Matter-certified TBRs will automatically create a robust Thread network, even if the owner doesn’t know what Thread is.
The CSA’s Matter 1.4.2 update sets new, separate performance requirements for these device types: certified Wi-Fi Access Points must support at least 100 simultaneous associations, while certified Thread Border Routers must support at least 150 devices and be Thread 1.4 certified.
What’s the progress so far?
The code repository, named “matter-openwrt,” is an OpenWrt feed that packages Matter software components. According to the project’s documentation, it is part of a reference implementation for the HRAP device type.
Recent activity shows the project is moving forward. A recent pull request, submitted by a developer from Apple, a major promoter of Matter, details the next steps. The pull request integrates the Matter network-manager with the existing OpenThread Border Router (OTBR) package over “ubus” and updates other key components like the mDNSResponder.
This “ubus” integration is the critical technical “glue” for this to work. On OpenWrt, It builds the bridge that lets the new Matter network-manager (the “admin”) securely send commands to the separate OTBR service (the “radio worker”) for commands and information exchange. This pull request effectively builds that communication line between them. This development also moves the project’s build target to the latest OpenWrt 24.10.4 release.
It is important to note the project’s specific focus. According to public discussions on GitHub, the project is not intended to turn an OpenWrt router into a Matter Controller or a Matter Bridge. Its sole purpose is to implement the “Matter Network Infrastructure” (MIN) device type, allowing the router to securely manage the network for other Matter devices.
OpenWrt is an upstream key
This development is significant because OpenWrt, one of the largest open-source router projects, serves as the “upstream” software for countless commercial routers on the market, even if many vendors do not publicly disclose this.
This effort from the CSA runs in parallel with similar work from the Thread Group, which has been adding OpenThread Border Router (OTBR) features to OpenWrt. Members of that group, like Silicon Labs, already release pre-built packages and SDKs to make their MG-series radio chipsets work with OpenWrt, primarily for platforms like the Raspberry Pi 3B. The combined work from both CSA and the Thread Group can better accelerate the adoption of all-in-one Matter- and Thread-capable routers.
How to try it?
As of now, there are no pre-built OpenWrt firmware images that include these new Matter components. Furthermore, OpenWrt firmware is model-specific, so it will likely be challenging to get the features ready for all supported router models.
This project is limited to developers and advanced users who are experienced in compiling OpenWrt from source. Those users can follow the official guides in the “matter-openwrt” repository to build the firmware for their specific hardware platform.
In the meantime, if you are interested in alternative OpenWRT and OpenThread options without Matter NIM features, you can try out GLiNet’s S200, which includes a fancy Thread Topology Interface.
(Source: GitHub, Image Source: Gemini, GLiNet)
