Considering WiFi7? Things To Be Aware Of

Articles & Guides Desktop & Apps
, ,
1

I recently upgraded my dual-boot Windows 11 / Fedora machine to a motherboard with WiFi7, and learned some things that might - or might not - be helpful to those considering a WiFi7 upgrade. I won’t take all the credit - Julien Turbide’s blog post has a very thorough discussion of what he did and discovered, and it provided me with some important a-HA! moments.

WiFi7 differs from earlier WiFi standards in a very important - and frustrating - way. A WiFi7 interface self-configures to the regulatory domain (i.e., geographic region or country) by listening for signals on all of the defined 5 GHz and 6 GHz channels and comparing this to established profiles for each country. NOTE: I will use “country” in the rest of this post instead of “regulatory domain”.

Self-configuration is done every time a WiFi7 interface is started. My computer is off more than it is on - so self-configuration is being done for every boot-up.

The process of self-configuration may take anywhere from seconds to minutes to complete. Success or failure depends upon the signals received on the defined channels in the 5 GHz and 6 GHz frequency bands. This includes WiFi access points, other possible licensed users of these bands, and any interfering noise - atmospheric, solar, or man-made - that may be present.

Self-configuration is not fool-proof. It is possible for an interface to fail to identify the region it is in, which will limit the interface to low-power transmit/receive on the 2.4 GHz band. See Julien Turbide’s blog post for both his findings, as well as an example of a script to force a WiFi7 interface to re-scan on interface start-up.

Licensed users of the 5 GHz and 6 GHz bands are defined by country. Licensed users may include military, government, spacecraft, amateur (ham), and/or commercial radio systems. For example, in the U.S., the 6 GHz band may (still) have point-to-point telecommunications systems (I know of one system in a rural area of northern California that’s probably still active). A list of potential conflicts can be found (among other places) at Wikipedia.

Unlike earlier iterations of WiFi, it is not possible to force the country by using either iw reg set or by manipulating the wireless-regdom file. With earlier versions of WiFi, it is possible to force a WiFi interface to a particular country - such as the U.S. - when a computer is located in a country - such as Greece - where some of the transmit channels will cause harmful radio interference.

With all that said…the biggest issue I encountered is that disabling Secure Boot on my machine - whether intentionally or by booting a “Live ISO” of Fedora 43 from a USB stick - disabled the WiFi7 interface on my motherboard. I am not sure if this is an intended security feature, or if this is a BIOS bug. But…after resetting the CMOS 4 times, I downgraded my machine to a WiFi6 interface.

9 Likes
Weekly Forum Summary
Weekly Forum Summary
2

Hey @ejkeerbs

This is a solid write up, thanks for sharing your experience with this.

The Secure Boot issue you hit is interesting. I’ve seen similar behavior where certain newer wireless chipsets just refuse to initialize without Secure Boot enabled, and it’s usually tied to the firmware loading path rather than being an intentional security feature.

The kernel needs to load signed firmware blobs for the radio, and some of these newer WiFi 7 chips are strict about the chain of trust. Disabling Secure Boot can break that chain and the firmware just won’t load.

The fact that you ended up going back to WiFi6 is honestly probably the right call for most Linux users right now. WiFi7 support is still maturing on the kernel and driver side. WiFi 6 is going to give you a much more predictable experience with way less headache.

I appreciate you linking to Julien Turbide’s blog too, that’s a good resource for anyone who wants to dig deeper.

3

Maybe I should have led with a TL;DR summary of “use WiFi6 for anything but a dedicated Linux workstation that always secure boots” ? :zany_face:

1 Like
4

One other observation to add.

I recently purchased a Lenovo laptop that only has WiFi7. I ordered this system with Fedora 42 pre-installed, and have since reformatted the SSD and installed Fedora 43.

I have found that allowing the WiFi 7 interface to connect to the default SSID on my T Mobile Home Internet router (supports 2.4, 5, and 6 GHz simultaneously) results in download speeds under 1 Mbit/sec. - even when connected to one of the 6 GHz channels.

I created a second SSID that only supports 5 GHz channels, and when I force the WiFi7 interface to connect to that SSID, download speeds are more tolerable (2 to 8 Mb/sec).

Note that these download speeds are with a VPN connection active. Deactivating my VPN improves download speeds, but I’m not willing to do that.

So, clearly, it is possible to have a system that only has WiFi7 work with Linux.

3 Likes
5

Are these speeds what you’d expect from your connection?

This is the first time I’ve read about WiFi 7 and its self-configuration process. My initial reaction is that it sounds like they are trying to lock it down even more, so I’m quite disappointed in this.

2 Likes
6

Two questions. And, I hope, two answers that make sense.

Let me start with the question about WiFi 7. Yes, in so many words, the various government regulatory bodies are trying to prevent users from configuring (hacking?) their WiFi interfaces. That also prevents a user from forcing a valid configuration in the event that self-configuration fails. For all intents and purposes, the regulatory bodies see no difference between forcing a valid configuration and hacking an interface.

As for my download speeds, well, they’re pretty consistent with what I’ve seen since switching to T Mobile and running a VPN. I have one computer using WiFi 6, two computers using WiFi 6E, and one computer using WiFi 7, and - with the caveat of forcing the WiFi 6E and WiFi 7 computers to a 5 GHz SSID - the speeds I’m seeing are consistent among the computers.

3 Likes