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A decentralized peer-to-peer messaging application that operates over Bluetooth

bitchat.free

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Re: A decentralized peer-to-peer messaging application that operates over Bluetooth

#351
post #27

Earlier quoted context omitted.

One of these bluetooth messaging app was made by a developer who was on a cruise ship with family, and the Internet over satellite costs an arm and leg. So he wrote an app to communicate with his families over bluetooth. Also why would one want to have the data go over some servers thousands miles away when the device is right next to you? Seems like bluetooth is the perfect way to communicate for devices that are cl…

Still, wouldn't a wifi meshnet be a better choice for these scenario's?

Went down that rabbit hole a while ago. iOS works fine, but think they may have discontinued ad-hoc, or at least on macOS. Android has a bit issue with ad-hoc hot spot at that time. [1] But theoretically it should be able to do that.

https://android.stackexchange.com/questions/28551/why-cant-a...

Re: A decentralized peer-to-peer messaging application that operates over Bluetooth

#352
post #312

Earlier quoted context omitted.

Yes. There's a lot of things to work out. Here's one scenario: Node A has a message to send to node H, but A is disconnected (no peers). Node A stores this message for eventual delivery. Eventually, node K (ie "any valid peer") appears. Node A gives them the message that is intended for node H and rinses its hands of it. Does node K's possession of this message actually improve the odds of node H ever receiving the m…

In theory, yes. There are now two nodes with the message for H. In practice? A and H might live in the town and K might be just visiting for business, they might never come back.

Well, no: In the scenario I outlined, there's now still just one node with the message for H. A passed it to K, and promptly forgot about (having passed it along to "any" valid peer).

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In your scenario, both A and K store the message for H -- suggesting replication (or perhaps, redundancy) by visiting peers. And maybe replication is OK.

It seems obvious that it can spiral out of control, but our pocket supercomputers do have a fair bit of bandwidth even at Bluetooth speeds, and flash memory is very cheap and available (a gigabyte of flash can hold a lot of short-ish text messages and costs very little).

So the network can afford quite a lot of replication in an effort to promote distribution -- and maybe that can work. Maybe the message isn't stored by just A and K, but also E, I, O, and U because they happened to stroll by and see the outbound message for H.

But there must be limits, if for no other reason than without limits then any single bad actor can ruin the whole works by exceeding the bandwidth and storage capabilities of the network.

These limits could be hop-based, or time-based, or geography-based, or any/all of the above.

Suppose a message lives until any of 50 hops or 5 days or 50 miles is exceeded? Yeah, maybe something like that works. The capabilities can be mathed to find some version of "ideal," and probably enforced somehow to prevent bad actors from doing too much bad stuff.

(But we're very rapidly straying very far from Fidonet's normal distribution behavior here, and dismantling that concept was the main crux of how I got to thinking about these things may theoretically work to begin with.)

Re: A decentralized peer-to-peer messaging application that operates over Bluetooth

#353
post #346
post #202

Earlier quoted context omitted.

I actually wrote a Noise implementation and someone wanted to make a Bitchat implementation with it, but my impl only supports BLAKE2B (and I got the impression this person really didn't know what they wanted to do in the first place). It's kinda sad more haven't moved to BLAKE2B (or BLAKE3, which I almost never hear anyone talking about).

Wasn't BLAKE2s recommended on the Noise mailing list, being faster for low volume messages, even on 64-bit?

I'd have to check but I believe so.
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