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by mytailorisrich 145 days ago
Lora, especially on regulated bands that are the most used ones, is designed for very small, very infrequent messages. It isn't suited for real-time chat (nevermind secure) and so I think you can't really make it work while respecting transmission regulations.

There are lora modules that work on the 2.4GHz ISM band but then you probably need to consider whether Bluetooth is not a simpler choice if range is not the no. 1 concern.
1 comments
BSDobelix 145 days ago
>It isn't suited for real-time chat (nevermind secure)

It is encrypted on private channels and direct messages.

>and so I think you can't really make it work while respecting transmission regulations.

I don't know from where your information's are from, but for sure not from reality. Voice encryption/scramble on Amateur-Band's is not allowed, everything else is ok.

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beala 145 days ago
> Voice encryption/scramble on Amateur-Band's is not allowed, everything else is ok.

It seems like you're saying voice encryption is not permitted, but data encryption is? This is not true in the US. Any encoding used for the purpose of "obscuring meaning" is not permitted on amateur frequencies. Even using code phrases like "the eagle has landed" is arguably not allowed. There are some narrow exceptions for things like satellite control codes, but nothing that applies to hobby mesh nets.

Here is the relevant Part 97 rule: https://www.ecfr.gov/current/title-47/part-97#p-97.113(a)(4)

> No amateur station shall transmit: [...] messages encoded for the purpose of obscuring their meaning, except as otherwise provided herein; obscene or indecent words or language; or false or deceptive messages, signals or identification.

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selimthegrim 145 days ago
So numbers stations fall under as otherwise provided?
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beala 145 days ago
No, numbers stations are not permitted on amateur frequencies in the US. There are some notable cases of foreign governments setting these up and interfering with amateur allocations [1], but there's not much the FCC can do about that.

[1] https://www.arrl.org/news/russian-buzzer-disappears-chinese-...

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mytailorisrich 145 days ago
I know what features it claims to have. The question is how well this can work on bands (US915, EU868) that very strictly limit the amount of time a device may transmit. IMHO you can't really have interactive chat on a mesh network over lora in those bands.
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BSDobelix 145 days ago
>I know what features it claims to have.

Yeah...no i don't think so.

>IMHO you can't really have interactive chat on a mesh network over lora in those bands.

Devices allow 10% Airtime on ISM here (EU) that's about 300 messages (with 255 characters) per hour, and yes interactive chat is possible with around 20 seconds of lag.

EDIT: I stop here, so much half knowledge that sounds educated but is in fact just wrong and TBH not even sure if i talk to a selfhosted AI.

Have a good Day.

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mytailorisrich 145 days ago
Yes, in the EU one subband allows 10%, the rest is 1%. I believe that Meshtastic uses the whole 250kHz of that subband by default. This is by far the most relaxed constraints of what is available in the EU and US. That's about 180 max. size messages per hour (at longfast) per device but you need to take into account retransmissions, acks, mesh management and routing of third party messages. So it may work, barely, for this specific config and very small number of people or 1-to-1, but that's it.

I am not picking on Meshtastic specifically, it's just that Lora and, especially the regs on those bands are such that some applications are never going to work well beyond extremely small meshes, if at all.

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BSDobelix 145 days ago
>I believe that Meshtastic uses the whole 250kHz of that subband by default. This is by far the most relaxed constraints of what is available in the EU and US.

Again wrong, just look at EU vs US:

https://meshtastic.org/docs/configuration/radio/lora/#region

> beyond extremely small meshes, if at all.

180 online nodes (300 at max) is not extremely small (and that's our small mesh EU with medium_fast)

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mytailorisrich 145 days ago
How many text messages does each user send per hour? Or how many are in active chat with each others at a given time?

(Careful that the US have a 400ms dwell time depending on settings that can put a significant limit on things/range)

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