802.11ah Wi-Fi HaLOW

This is a standard for longer range WiFi. The implementation is in the 900Mhz band. The chips are from Silex Technology America, Inc. and Morse Micro Pty Ltd. they offer a Linux driver. My thought is to replace one radio of a two radio router box with the 802.11ah radio module for development . The end use will be in Areden (Amateur Radio Emergency Data Network) based on OpenWrt.

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Is this Areden system "based on OpenWrt" or is it running the the official version?

What is the output of:

ubus call system board

It is a special version https://www.arednmesh.org/content/supported-platform-matrix

In that case, you need to ask the aredn people... we have no way to know how they have modified OpenWrt, nor would we be able to advise on integrating new radios (and associated drivers) into their firmare.

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A link that shows their Git pages ca n be found at the link.

Long range 802.11ah incorporated into Openwrt would benefit all users.

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That may be true, but if you're trying to implement it in the aredn environment, you need to talk to them.

If you want to implement it in official OpenWrt, you can certainly load the OpenWrt code, fire up the build system, and start developing/porting the drivers for the 900MHz radios that you're looking at. Contributors in the developers section of the forum are often quite responsive when people have detailed questions during development.

https://openwrt.org/docs/guide-developer/start

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Still not a single driver in mainline kernel, nor hostapd support, but when those come around somebody has to script usermode for new frequency band and everyone benefits. And you do not even need special communication libraries as you get just a common looking wifi IP network....

Hi there, I had a similar idea (I think) using this Raspberry Pi module:

I do not have any experience messing with WiFi devices except been running OpenWRT on all my home routers and a bunch of Aredn nodes.

I do have lots of experience with building/compiling Linux kernel and networking in general.

My basic hypothesis, with respect to Aredn usability, is that the 5ghz band is excellent to service as backbone mesh network but given line of sight requirement, it is nearly useless for any “field” operators. If each Aredn 5ghz node was equipped with a 900mhz AP then a “field” or “roaming” operator could easily connect to the mesh and relay information (audio/text or whatever the 900mhz spectrum will support). Given regulatory and technical limitations, number of clients supported on 802.11ah look like they will be limited but I think it will open up the Aredn mesh for actual use. I feel like right now, the 5ghz mesh provides an excellent platform but has no “customers”. People have cameras and random apps hanging off their nodes but nothing of use really. And if you are mobile, like actually on the move or do not have line of sight to a node then the whole thing fairly useless. Going down in the range, 400mhz has more latency and bandwidth limitations and 2.4ghz doesn’t propagate as far. I think 900mhz is perfect even if it is limited in terms of number of concurrent connections it can support per AP.

Thoughts/Suggestions? All this is just an idea in my head now. As I type this, I have two of those Raspberry Pi HAT modules in a cart along with some other Pi accessories :slight_smile:

Thoughts and suggestions don't magically wish the necessary code onto the table - and there is no support for this in the mainline kernel at this points, where it needs to be.

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Sorry, I understand how I might have crossed some wires here. I am not expecting any magic or anyone else to do the work of creating or integrating the necessary drivers/code in the kernel tree. I was more curious about what do forum members think about the idea. Like I said, I don’t have any experience implementing various 802.11 standards and neither am I very familiar with the OpenWRT project except as a user. So before I dive deeper, I was hoping for some feedback if there are any obvious gotchas. I think I can take this thread to the developer forum or Aredn forum. Thanks all.

In that noob context: "it does not work"

Care to expand on “it does not work”?

a) we would like to see 802.11ah support in OpenWrt
b) but someone will have to do the necessary development work
b.1) first in the mainline kernel (nl80211(!) and regd(!), then drivers(!))
b.2) then in hostapd
b.3) then in OpenWrt (netifd, wpad)

With a) assumed to be positive (after all that part is just wishful thinking), the question is all about b) - and that's firmly in the negative for every (sub-)point. The kernel doesn't know anything at all about 802.11ah, it doesn't know what to do with the frequencies, the channels, it has no regulatory information about them and there are no drivers (which covers everything of b.1)). Without b.1) anywhere (at all), there's no point thinking about b.2) - and without b.1) and b.2) completed, there's no point even talking about OpenWrt.

…or, as rightly phrased, "it does not work" - and it will never work, until the chipset manufacturer works on mainlining their drivers (and for that to happen, they will have to extend nl80211 before and get those changes approved/ merged). As none of the 802.11ah vendors have bothered about this yet, nor (apparently) even started discussions with the kernel's mac80211 maintainers yet, I wouldn't expect that to happen, probably ever. With the changes involved, I would expect the nl80211 side changes to require considerable discussion and review, before the driver changes are even up for review.

It's 'possible', but the proponents don't seem to care - so chances are nil, until that changes fundamentally. If the manufacturers were heavily motivated and invested, this would easily take 1-2 years to (potential) completion (really, if $vendor wants to introduce new features (in the scale of new standards with larger stack changes), get involved while it's still in the whiteboard phase of the standard, long before initial tapeout) - if they're good, they'll have their ducks in a row by the time their hardware starts shipping - if they neglect this, they're going nowhere fast.

Hello!

We haven't forgotten about the open source communities and this is an area we intend to invest more effort in very shortly!

It's worth noting we have begun engaging the kernel and some user space applications to begin moving this effort. See
https://patchwork.kernel.org/project/linux-wireless/list/?state=*&q=s1g&param=2&page=1
https://patchwork.ozlabs.org/project/hostap/list/?series=&submitter=&state=*&q=s1g&archive=&delegate=

Our evaluation kits, available on mouser, are OpenWrt based so we can help support those using our SDK with HaLow integration. Unfortunately the patches aren't suitable for upstream yet, but we intend to start pushing these patches up soon.