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Groxx 9 hours ago

having read that meshtastic section: I mostly agree with their requests tbh. the only suggestions in there seem to be "use full duplex" (with approximately one reason why, though it's a good one) and "solve frequency discovery with SDR" which they've already addressed as somewhat ridiculous - because it is, for someone interested in a low power and low cost network.

particularly the SDR stuff, which is the VAST majority of that section. this is not at all the same target audience as meshtastic:

>A computer with “sufficient” compute power and RAM, to run the ka9q-radio software. KA9Q has stated that a Raspberry Pi 4 is sufficient, and now we have the Raspberry Pi 5 with up to 16 GB of RAM, for only $120.

that's like suggesting the way to fix a wireless problem is to use a wire. otherwise the criticism seems to summarize as "it's slow and bad" and well. okay? that's hardly constructive, whether or not it's accurate.

the whole thing reads like "the solution is left as an exercise to the reader ;)" because it sounds like it's written by and for people who are already experts and just want to read a cathartic list of flaws they already know. and/or "buy better hardware lol". it's not at all the logical slam-dunk that you seem to think it is.

bb88 2 hours ago | parent [-]

Meshtastic can only use one frequency at a time. So, say, a battery status update can stomp on a message trying to get to a meshtastic router. (He's got the link to the hidden node problem with a great wikipedia article about it).

The more popular the network, the more frequent these message stomps happen. Flood routing makes these stomps more frequent.

There is also no end to end packet acknowledgement system like tcp, so at hop 3 (e.g.) if the message got stomped on, who would know?

Let's say someone made a dual band lora transceiver. Well that would help, but it wouldn't solve anything else, because there's still core routing/reliability/topology issues.

So if you had 20 channels to talk over, well that would be even better. The chance of having your message stomped on would go down significantly making the network much more reliable. That's the SDR part (the listening of 20 channels at once) vs the Lora chip which can only listen/transmit on 1 channel at once.

Edited to add:

"But that's super expensive hardware/engineering to do that!" you might say. Well, it's being done today.

The point is that if you can fit 20 1khz channels in a 20khz RF space. The 20khz RF can be converted into audio and fed into a soundcard and processed. This exists today with FT-8, though FT-8 uses 150hz bandwidth per stream in 2.8khz sections per band.

You can see some FT-8 activity by looking at some websdrs.

Maybe go here and tune to 14.074Mhz Upper Side Band (USB)

http://data3.caprockweather.com:8073/

Each vertical line is one message 150hz wide.

wtallis an hour ago | parent | next [-]

I still don't see how your suggestions amount to anything other than telling people to spend a lot more money on completely different hardware and use it in a completely different manner.

FT-8 doesn't seem usefully relevant here. The fact that the bandwidth is so low that it can be sampled with a sound card isn't at all helpful when Meshtastic doesn't require a PC. And FT-8 carries minimal payload (typically amounting to no more than the automated status updates you dislike Meshtastic wasting airtime on), and I've never heard of anyone doing routing over FT-8. You're just making noise about a completely unrelated niche radio hobby.

If the constraints of LoRa and Meshtastic don't make it possible to implement the kind of radio system you want to play with, that doesn't prove that Meshtastic has made any wrong decisions. It just says you would get a more fulfilling experience from getting into a different radio hobby, and stop getting in the way of potentially productive discussions about how Meshtastic could be improved within the constraints of the currently-existing commodity hardware.

Groxx an hour ago | parent | prev [-]

yeah, that's exactly what I was referring to as "use full duplex" (use at least 2 frequencies, I agree this sounds like pretty solid critique (particularly with meshcore's network setup) and wouldn't make hardware dramatically more expensive) and "buy better hardware lol" (use 20+ frequencies and make it a completely different product at a MASSIVE price increase. why not just suggest wires then).

so there's one bit of probably-usable advice (slightly raise cost for significant benefits) and one that completely misses the point (charge at least 5-10x more for wildly different hardware, use hundreds of times more power, etc). the article spends several times more text on the latter.

flood routing and lack of end to end ack I also agree with, I sincerely doubt those are the best options and if user complaints are any sign then I think it's an existence proof that it doesn't scale, exactly as predicted. neither are part of that article, though it is in a linked also-large mastodon thread, which has basically just one constructive suggestion (8x the channels, though they don't think it'll work either) and many "this sucks" examples (flood fill, hop limit, etc. it amounts to "do better", not "X is better, learn from it").