#Decentralized Chatroom through subghz

82 messages · Page 1 of 1 (latest)

cinder ferry
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i have a cool idea for something like pictochat but on the flipper:

  1. generate a passkey or passphrase on one device that acts like a traditional 2fa key that you would normally put into an authenticator (to change the frequency to send and receive at on all flippers on that code)
  2. AES-type encryption to securely send and receive messages (hopefully this can be embedded in the code that is generated)
  3. this chat room could also be used to send files

to figure out:

  1. securely sending the key for the chat to participants (no fakers!!) -- we could use the serial key for the device to identify participants (like how iphones use it for imessage) but anyone can fake it and we wouldn't know who is who
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something that could be difficult to accomplish is sending that key that you generate to participants of a chatroom without bringing in unauthorized listeners

shadow pollen
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little addition to the encryption, could encrypt the AES keys with RSA just for the fun of it

shadow pollen
cinder ferry
shadow pollen
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And sending messages back

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Could check out the matrix system code and see if that can help

cinder ferry
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true

shadow pollen
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Shouldn’t be too hard to search through everything

cinder ferry
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oh shit i though you were saying matrix as in the movie

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thanks though lmao

shadow pollen
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Nah matrix as in the decentralised chat lmao

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I’m thinking it’s possible to borrow some of their stuff or get inspiration out of it for how to do it securely

mild basin
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@digital jewel is working on something like that

shadow pollen
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@cinder ferry your wish has been granted

cinder ferry
prime gate
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I mean I have a ds lite somewhere I can try to capture the signals sometime I’d have to dig it out tho

cinder ferry
prime gate
cinder ferry
prime gate
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I was thinking maybe make a proto board with a sat com type chip that can talk to any flipper by knowing it’s serial number or a choosen code then have it end to end encrypted, idk if it can be done but have a two way encryption that relies on the other flipper to revive a message and confirm it with the sender before your able to read it
Granted governments may not like that at all but it would be cool if possible and I made sense trying to type it out lol

shadow pollen
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I recon we actually get this done

prime gate
cinder ferry
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well damn

subtle sinew
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this sounds pretty cool, i know there's subghz chat out there

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you can do key exchange over an unsecured medium without being able to snoop in

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but as for the "no fakers" part, that's a bit harder, you need some way to prove identity of sorts (for example, that you really are this specific flipper) - you'd need a certificate for that, and a certificate authority to sign that certificate for you, a CA which you must trust

subtle sinew
prime gate
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yeaaa i have seen a few garmin

subtle sinew
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you're looking at something like a starlink receiver antenna, but that's Ku/Ka bands, so 10GHz+ and tiny antennas

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The phones which do uplink to a sattelite and don't have huge antennas, like iridium or globstar usually have dedicated frequencies, which is a major advantage to drown out the noise

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ngl, holding your flipper up to uplink to a sat would be awesome as hell

digital jewel
hollow ore
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Why not bluetooth? Also, you need some kind of input device. The on-screen keyboard is a bit limited and slow, something like this would be great

20221030_202240.jpg
subtle sinew
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I think the point is using the chat from console, at least at first

daring stream
daring stream
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but i might be wrong @digital jewel

subtle sinew
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since I assume talking with other flipper owners near, using flipper, you would be the purpose here

verbal marsh
daring stream
verbal marsh
daring stream
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unfortunately such information on flipper website might sometimes be incorrect, as it was written 2 years ago when we didn’t have real numbers, and we had to assume according to transceiver specs

daring stream
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probably achievable in plain sight

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@digital jewel knows more

daring stream
verbal marsh
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I wonder if there are any other ways to extend that 50m range, I did some perusing via google on the CC1101 chip, and it appears you can get up to 300-500m for some reason (assuming we don't have any obstructions/other external factors that can shorten the range)

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which is like 10x the range on the flipper, I assume its due to regulatory stuff, but nonetheless i wonder if that can be theoretically achievable

subtle sinew
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a lot of rf distance boils down to how you use your link budget

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you can transmit slower to up your budget, give the receiver a bigger antenna, make the receiver more sensible, use a frequency dedicated just for yourself (not ISM), use natural phenomena to improve propagation, and so on

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the only thing you actually have control over with FZ is data rate and frequency

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a bit offtopic: I wonder if you can synthesize a shitty lora chirp with CC1101.

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at SF12, you have to sweep through 125khz in 32ms, but I've succesfully coaxed my gateway to deal with stepped chirps (essentially MFSK with just a ramp up) with as low as 12 steps on SF7

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but if you get fake lora up, you're bound for some fun ranges, a lot of gateways in 10-15kms will react to you

subtle sinew
digital jewel
digital jewel
subtle sinew
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APRS has a pretty interesting messsage distribution tech which might work well for subghz chat, and it's almost like a mesh, but not really - however it's basic enough that you might not like it

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(also works since 1980 or whatever)

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if you hear a packet, you store it for a while, decrease its TTL by 1 and rebroadcast it after a short random interval

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if you hear a packet and it matches a stored packet, you don't broadcast it

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it solved the hidden node problem, it eliminates duplication, it doesn't need a FSM to compute mesh links in a graph, and it provides some amount of redundancy without actually having to do ACK/NAKs and needing to send even more packets

jade spade
solar tusk
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20m... I guess you can't do something like LoRa on the light radio stack. As for the chatrooms, you probably could modify existing code to just send messages similarly to how it's done now but encrypt the payload, add a checksum and by default hide improperly decrypted messages.

atomic coyote
tawny warren
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I would like to use flipper like a pager

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And would like a tx/rx morse function

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chatting with pagers in 439,98MHz x)

iron coral
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portable-secrets is kinda cool. No good for chatting. of course.

atomic coyote
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It doesn't communicate with pagers

tawny warren
atomic coyote
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via CLI, you can do it tho

tawny warren
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yes I know, that's cool 😁

jolly blade