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Updates to irl blog post

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Ana Custura 2026-04-15 14:11:19 +01:00
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@ -31,11 +31,11 @@ into a future release.
## WiFi HaLow
Traditional WiFi operates at 2.4GHz, 5GHz, and up to provide high speed connections between local devices.
Traditional WiFi operates at 2.4GHz and 5GHz, and aims to provide high speed connections between local devices.
The higher the speed, the higher the frequency of the carrier required, and pushes in this direction have led to the
development of the WiGig standard offering multi-gigabit speeds operating at 60GHz.
There is a tradeoff however that as the frequency increases the distance that the signal propagates and the materials
it can propagate through both decrease.
There is a tradeoff however: as the frequency increases the distance that the signal propagates and its ability to
propagate through materials both decrease.
WiFi HaLow is IEEE 802.11ah, a wireless protocol that takes WiFi and moves it down below 1 GHz. This is 863-870MHz in
ITU region 1 and some countries in region 3, and 902-928MHz in region 2.
@ -43,19 +43,19 @@ Being in this lower frequency range means that signal can propagate further and
materials like those found in urban environments.
To be compliant with the local rules governing radio spectrum use, the transmissions must be entirely contained within
the available frequency range and for data transmissions there can be some "spillover" affecting nearby frequencies from
the available frequency range, as for data transmissions there can be some "spillover" affecting nearby frequencies from
the signal.
In region 2, including the United States, there is a full 26MHz available allowing for 8MHz wide channels and a
theoretical maximum throughput of 43Mbps.
In regions 1 and 3 however there is only 7MHz available allowing for a 2MHz wide channel with maximum theoretical
throughput of 8.9Mbps.
The trade-offs is straightforward: you sacrifice throughput for range.
The trade-off is straightforward: you sacrifice throughput for range.
HaLow promises roughly 10× the range and 100× the coverage area of conventional WiFi, which matters when you're rapidly
deploying an ad-hoc network responding to an evolving situation.
It is not a replacement for the WiFi that carries your video calls.
It is a means of tactical communication and dissemination of updates received from outside the network, allowing for
the exchange of critical messaging and maintaining situational awareness for responders during communications outages.
It is not a replacement for the WiFi that carries video calls, but rather a means of tactical communication and
dissemination of updates received from outside the network, allowing for the exchange of critical messaging and
maintaining situational awareness for responders during communications outages.
In our evaluation of WiFi HaLow, we used the Morse Micro
[MM8108-EKH19 Evaluation Kit](https://www.morsemicro.com/resources/product_brief/MM8108-EKH19-Product-Brief.pdf) which
@ -124,7 +124,7 @@ devices competing for spectrum. (Check out the
[Morse Micro YouTube channel](https://www.youtube.com/@morsemicro) if you want to see some ideal environment tests, like
this one [achieving 3km range along Ocean Beach, California](https://www.youtube.com/watch?v=2xlUijXucoM)).
At 500 meters it was still possible, albeit frustrating slow at times, to access the Butter Box interface over the
At 500 meters it was still possible, albeit frustratingly slow at times, to access the Butter Box interface over the
bridge. At that distance, it would be practical to have a second Butter Box to provide an interface and Delta Chat
relay, and then allow the relays to communicate over the bridge but keep other interactions local. Delta Chat is built
on email which was designed to be delay tolerant from the start and so is well suited for this use case.
@ -166,7 +166,7 @@ They were labelled as "USR-LG206-P" and while we were unable to obtain a datashe
We confirmed that data could indeed be sent over greater distances than WiFi HaLow in our initial testing however this
throughput was not suitable to attempt to load the Butter Box portal.
One possibility that we would have explored given more time would be to run UUCP over the emulated serial link.
One possibility for future exploration would be to run UUCP over the emulated serial link.
The necessary software for this [is maintained in Debian to this day](https://packages.debian.org/sid/uucp) and would
be ready for configuration in a custom Delta Chat relay configuration.