5 ms·

The "100x bandwidth" claim needs to be substantiated. There are some significant regulatory issues with the current popular mesh network protocols in the USA,

The "100x bandwidth" claim needs to be substantiated. There are some significant regulatory issues with the current popular mesh network protocols in the USA, namely that neither MeshCore or Meshtastic are compliant with the actual FCC regulations. 100x bandwidth because you're breaking the rules isn't the same as 100x bandwidth legally. Here is the issue discussing this in the MeshCore repository: https://github.com/meshcore-dev/MeshCore/issues/945 https://github.com/meshcore-dev/MeshCore/issues/945

wtallis 5mo ago
The issue you linked to is about MeshCore using channels that are too narrow. A mesh system claiming to offer 100x bandwidth is probably not violating regulations in that particular way.
- nunobrito 5mo ago
  There are more rules being broken. For example, overusing the frequency which effectively prevents others users from sending messages. In the end, won't be used.
  - nubinetwork 5mo ago
    In the EU, the duty cycle limit is like 10% per hour. North America doesn't have that restriction...
    - slow_typist 5mo ago
      Not on the 2.4 GHz band though
      - deleted 5mo ago
        [deleted]
      - nubinetwork 5mo ago
        Our local discord questions the use of 2.4ghz for longer than 50 feet, between WiFi and Bluetooth, microwaves, and millions of "2.4 GHz (nonspec) wireless devices", the spectrum is just trashed.
        slow_typist 5mo ago
        For lora applications or in general?
        nubinetwork 5mo ago
        Both ;)
        subscribed 5mo ago
        Halow works though.
    - nunobrito 5mo ago
      Ah, thanks. Had the idea the duty cycle restriction would be common. Thank you for the update.
      - Joker_vD 5mo ago
        That would violate the First Amendment. /s
    - mytailorisrich 5mo ago
      I believe that they usually have a maximum dwell time, thoughs sometimes over a specific period (in which case it it equivalent to duty cycle)..
- colanderman 5mo ago
  Correct. The LoRa configurations mentioned which offer 100× the speed of Meshtastic/Core operate at 800 kHz and 1.6 MHz bandwidth, which are permitted by the FCC in 15.247. As far as I know there's not actually anything particular to 2.4 GHz allowing higher throughput for LoRa than that the corresponding Semtech chip happens to support wider bandwidths. (I.e. no legal barrier.) The tradeoff is less range due to lower link budget. Doubly so because 2.4 GHz has higher free-space path loss. You're not going to get outside your house with these speeds. The primary use (as stated in the original post) is likely through clear space with a directed antenna. (The 2.4 GHz band is better suited to this use since you can use antennas with higher than 6 dBi gain. If my math is correct, anything higher than 11 dBi is a win even accounting for FSPL and the power derating the FCC imposes.) (Aside, I am the author of that MeshCore ticket.)
  - nerdsniper 5mo ago
    What issues does it create for others to use too narrow of a bandwidth? Why “should” the FCC care if someone is only using a small portion of the spectrum that would otherwise be fine fr them to use? Thanks for educating us!
    - colanderman 5mo ago
      Spectral power density is the primary concern. The legal power limit in these bands is 1 W. If you spread that out over 500 kHz, that signal is weaker than background noise at any given frequency for anyone more than about a city block away. (Give or take many factors.) But, if you compress that 1 W into, say, 12.5 kHz (typical for FM voice), your signal is now detectable (and will interfere with other, possibly licensed, users) at over 6 times the distance. There are probably other factors. For example, it's not legally sufficient to simply reduce your power by a corresponding factor. I suspect it may simply be the FCC's goal to reduce conflict between users by mandating spread-spectrum technologies for unlicensed use. Note also that 47 CFR 15.247(e) [1] gives a spectral power limit which corresponds approximately with the 1 W max / 500 kHz min specified in (b)(3) and (a)(2). Final side note – https://docs.fcc.gov/public/attachments/FCC-02-151A1.pdf https://docs.fcc.gov/public/attachments/FCC-02-151A1.pdf is interesting reading as to how the current form of 15.247 came to be. Specifically it changed the rule from specifically DSSS to digital modulation generally, which in turn allowed the transition from 802.11b (DSSS) to 802.11g (OFDM) on 2.4 GHz. [1] https://www.ecfr.gov/current/title-47/part-15/section-15.247#p-15.247(e) https://www.ecfr.gov/current/title-47/part-15/section-15.247...
- ingohelpinger 5mo ago
  i am just reading "its not allowed" "rules are being broken" "not premitted" lol. how should you invoate and break free from the current ISP model, if everythig is not premitted?
rocqua 5mo ago
That's just "using lora in the same band as WiFi and Bluetooth" no?
- Neywiny 5mo ago
  At least the start of the discussion is around the 915 MHz band which is not WiFi/Bluetooth
- colanderman 5mo ago
  The 915 MHz, 2.4 GHz and 5.8 GHz bands are regulated in the US largely in the same manner, see https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A/part-15/subpart-C/subject-group-ECFR2f2e5828339709e/section-15.247 https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A...
RobotToaster 5mo ago
Seems more of an issue of outdated and de facto unenforceable regulations than an issue with the protocol.
- st_goliath 5mo ago
  > de facto unenforceable regulations I guess you have never encountered the anger and wrath of a retiree who's into ham radio and has the regulatory office on speed dial.
- altairprime 5mo ago
  In the U.S. I believe the FCC has federal authority to knock down your door, if they can pinpoint an illegal interference emanating from within your home. Intent is not particularly a factor in that, since interference can have a large radius and be unintentional. Seems like an awful time to be intentionally emanating ‘de facto unenforceable’ illegal signals.
zoobab 5mo ago
"regulatory issues with the current popular mesh network protocols in the USA" There are other countries in the world. And there are also places where there is no electromagnetic policies (think about over the oceans).
aaron695 5mo ago
[dead]
DoctorOetker 5mo ago
I never understood the popularity of these protocols, because when I looked at the legal duty cycles and multiplied that by time in a day and instantaneous bitrate, the result was a disappointing amount of data per day... So many spectrum rules are totally weird though: should they be interpreted per radio device? or per user? What -apart from cost- prevents a user who wants more bandwidth from installing 10 devices in parallel and alternate each radio so none of the radios exceed their allowed transmit duty cycle?
- davemp 5mo ago
  > What -apart from cost- prevents a user who wants more bandwidth from installing 10 devices in parallel and alternate each radio so none of the radios exceed their allowed transmit duty cycle? Folks with badges knocking on the user’s door. It is pretty trivial to locate stationary signals.
  - andruby 5mo ago
    The point they are making is that if the limit is _per device_ than using 10 devices doesn't break the rules.
    - davemp 5mo ago
      The FCC or whoever is almost 100% just looking at power/time/location. Those 10 devices will look like 1 device.
      - DoctorOetker 5mo ago
        when would the 10 radios be sufficiently spaced to count as separate devices?
  - Zigurd 5mo ago
    Law enforcement that isn't solving 50% of murders also isn't looking for exotic crimes unless there's a lot of money in it for them.
- 5mo ago

wtallis 5mo ago

The issue you linked to is about MeshCore using channels that are too narrow. A mesh system claiming to offer 100x bandwidth is probably not violating regulations in that particular way.

nunobrito 5mo ago
There are more rules being broken. For example, overusing the frequency which effectively prevents others users from sending messages. In the end, won't be used.
- nubinetwork 5mo ago
  In the EU, the duty cycle limit is like 10% per hour. North America doesn't have that restriction...
  - slow_typist 5mo ago
    Not on the 2.4 GHz band though
    - deleted 5mo ago
      [deleted]
    - nubinetwork 5mo ago
      Our local discord questions the use of 2.4ghz for longer than 50 feet, between WiFi and Bluetooth, microwaves, and millions of "2.4 GHz (nonspec) wireless devices", the spectrum is just trashed.
      - slow_typist 5mo ago
        For lora applications or in general?
        nubinetwork 5mo ago
        Both ;)
      - subscribed 5mo ago
        Halow works though.
  - nunobrito 5mo ago
    Ah, thanks. Had the idea the duty cycle restriction would be common. Thank you for the update.
    - Joker_vD 5mo ago
      That would violate the First Amendment. /s
  - mytailorisrich 5mo ago
    I believe that they usually have a maximum dwell time, thoughs sometimes over a specific period (in which case it it equivalent to duty cycle)..
colanderman 5mo ago
Correct. The LoRa configurations mentioned which offer 100× the speed of Meshtastic/Core operate at 800 kHz and 1.6 MHz bandwidth, which are permitted by the FCC in 15.247. As far as I know there's not actually anything particular to 2.4 GHz allowing higher throughput for LoRa than that the corresponding Semtech chip happens to support wider bandwidths. (I.e. no legal barrier.) The tradeoff is less range due to lower link budget. Doubly so because 2.4 GHz has higher free-space path loss. You're not going to get outside your house with these speeds. The primary use (as stated in the original post) is likely through clear space with a directed antenna. (The 2.4 GHz band is better suited to this use since you can use antennas with higher than 6 dBi gain. If my math is correct, anything higher than 11 dBi is a win even accounting for FSPL and the power derating the FCC imposes.) (Aside, I am the author of that MeshCore ticket.)
- nerdsniper 5mo ago
  What issues does it create for others to use too narrow of a bandwidth? Why “should” the FCC care if someone is only using a small portion of the spectrum that would otherwise be fine fr them to use? Thanks for educating us!
  - colanderman 5mo ago
    Spectral power density is the primary concern. The legal power limit in these bands is 1 W. If you spread that out over 500 kHz, that signal is weaker than background noise at any given frequency for anyone more than about a city block away. (Give or take many factors.) But, if you compress that 1 W into, say, 12.5 kHz (typical for FM voice), your signal is now detectable (and will interfere with other, possibly licensed, users) at over 6 times the distance. There are probably other factors. For example, it's not legally sufficient to simply reduce your power by a corresponding factor. I suspect it may simply be the FCC's goal to reduce conflict between users by mandating spread-spectrum technologies for unlicensed use. Note also that 47 CFR 15.247(e) [1] gives a spectral power limit which corresponds approximately with the 1 W max / 500 kHz min specified in (b)(3) and (a)(2). Final side note – https://docs.fcc.gov/public/attachments/FCC-02-151A1.pdf https://docs.fcc.gov/public/attachments/FCC-02-151A1.pdf is interesting reading as to how the current form of 15.247 came to be. Specifically it changed the rule from specifically DSSS to digital modulation generally, which in turn allowed the transition from 802.11b (DSSS) to 802.11g (OFDM) on 2.4 GHz. [1] https://www.ecfr.gov/current/title-47/part-15/section-15.247#p-15.247(e) https://www.ecfr.gov/current/title-47/part-15/section-15.247...
ingohelpinger 5mo ago
i am just reading "its not allowed" "rules are being broken" "not premitted" lol. how should you invoate and break free from the current ISP model, if everythig is not premitted?

rocqua 5mo ago

That's just "using lora in the same band as WiFi and Bluetooth" no?

Neywiny 5mo ago
At least the start of the discussion is around the 915 MHz band which is not WiFi/Bluetooth
colanderman 5mo ago
The 915 MHz, 2.4 GHz and 5.8 GHz bands are regulated in the US largely in the same manner, see https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A/part-15/subpart-C/subject-group-ECFR2f2e5828339709e/section-15.247 https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A...

RobotToaster 5mo ago

Seems more of an issue of outdated and de facto unenforceable regulations than an issue with the protocol.

st_goliath 5mo ago
> de facto unenforceable regulations I guess you have never encountered the anger and wrath of a retiree who's into ham radio and has the regulatory office on speed dial.
altairprime 5mo ago
In the U.S. I believe the FCC has federal authority to knock down your door, if they can pinpoint an illegal interference emanating from within your home. Intent is not particularly a factor in that, since interference can have a large radius and be unintentional. Seems like an awful time to be intentionally emanating ‘de facto unenforceable’ illegal signals.

zoobab 5mo ago

"regulatory issues with the current popular mesh network protocols in the USA" There are other countries in the world. And there are also places where there is no electromagnetic policies (think about over the oceans).

aaron695 5mo ago

[dead]

DoctorOetker 5mo ago

I never understood the popularity of these protocols, because when I looked at the legal duty cycles and multiplied that by time in a day and instantaneous bitrate, the result was a disappointing amount of data per day... So many spectrum rules are totally weird though: should they be interpreted per radio device? or per user? What -apart from cost- prevents a user who wants more bandwidth from installing 10 devices in parallel and alternate each radio so none of the radios exceed their allowed transmit duty cycle?

davemp 5mo ago
> What -apart from cost- prevents a user who wants more bandwidth from installing 10 devices in parallel and alternate each radio so none of the radios exceed their allowed transmit duty cycle? Folks with badges knocking on the user’s door. It is pretty trivial to locate stationary signals.
- andruby 5mo ago
  The point they are making is that if the limit is _per device_ than using 10 devices doesn't break the rules.
  - davemp 5mo ago
    The FCC or whoever is almost 100% just looking at power/time/location. Those 10 devices will look like 1 device.
    - DoctorOetker 5mo ago
      when would the 10 radios be sufficiently spaced to count as separate devices?
- Zigurd 5mo ago
  Law enforcement that isn't solving 50% of murders also isn't looking for exotic crimes unless there's a lot of money in it for them.
5mo ago