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Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

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71–80 of 221 posts

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#71
post #38

Earlier quoted context omitted.

> the next step would to build higher powered repeaters that can be placed on top of tall buildings. Nice sentiment, but technically counterproductive for mesh networks. Wide coverage nodes create/suffer the “hidden transmitter problem”. Mesh performance degrades overall. Smaller footprint repeaters, and more of them, are a better solution.

> > the next step would to build higher powered repeaters that can be placed on top of tall buildings. > Nice sentiment, but technically counterproductive for mesh networks. Wide coverage nodes create/suffer the “hidden transmitter problem”. Mesh performance degrades overall. Smaller footprint repeaters, and more of them, are a better solution. Could you go into more detail on this/share any readings? As a ham radio…

The ham packet radio literature has the most readable descriptions. The professional RF networking write ups that I am aware of are pretty old because I have not followed networking much since grad school (back in the last millennium). Sorry about that.

Basically, you probably already know this, but for others reading along: The RF networking channel differs from a wired net in that not all stations can hear each other. So for stations of relatively equal performance, the stations on the edges do not hear each other and must relay through a station in the middle. It follows that those stations perceive channel busy/clear differently.

With a high level station, first off it hears many more stations so can not transmit into a clear channel as often. Then, when it does transmit, it has a large footprint and prevents channel re-use by several lower-level stations that would otherwise have different locally-clear channels.

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#73
post #54
post #34

Earlier quoted context omitted.

Hopefully OP uses a different cell network than the one Simple Mobile rides atop.

This kind of device matching can be done across any of the carriers or their MVNOs, all of them give up the data when asked by a government entity. Many tower locations will even be identical across carriers, making the matching even easier. Also this correlation could be done with stingray towers without bringing the cell carriers into the loop.

With the higher clustered protestors the tower linking won't be as identifiable as you might think.

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#74
post #67

Earlier quoted context omitted.

how do you skip verification? after hitting the cancel button the start screen shows again

Apparently you need to fail verification a few times before it'll present the option. I kept giving it bogus phone numbers and eventually a "skip" button appeared.

I wouldn't trust an app where the first thing you have to do is navigate dark patterns.

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#75

If worst comes to worst, I hope there's satellite connectivity to HK. Or landlines not under Chinese jurisdiction. EDIT: To clarify, I'm concerned about what could happen if China cuts HK off from the Internet.

Satellite phones are extremely easy to determine point of origin, give or take 20m. That's enough to dispatch police or worse, launch an airstrike.

That's exactly how Dzhokhar Dudayev was killed: using two laser guided missiles while he spoke on sat phone. The signal was interceped by a Russian reconaissance aircraft.

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#76

If worst comes to worst, I hope there's satellite connectivity to HK. Or landlines not under Chinese jurisdiction. EDIT: To clarify, I'm concerned about what could happen if China cuts HK off from the Internet.

China can't cut HK off from the internet. Almost all Chinese internet traffic is routed through Hong Kong, not the other way around.

I don’t think China would care about cutting themselves off from the global internet.

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#77
post #2

Using technology to bring down tyrants. The CIA should do something useful for a change and see this app is distributed to places like North Korea, Zimbabwe, Syria, Myanmar and Iran.

Honest question, but do most people in North Korea have personal smartphones which can connect to outside networks and aren’t completely monitored by the government?

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#78

Earlier quoted context omitted.

Not a bad point, but what business prefers a mesh to a centralized messaging system?

Businesses selling gas masks, helmets and med-kits?

Construction industry supply would prefer to sell you walkie-talkies

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#79

Earlier quoted context omitted.

I used a simple mobile "burner" and was fine to authenticate. I bought bunch of $5 cards with cash in a small store and used this one in my dumb flip phone bought on a flea market few months ago. I am certain to a high degree that's pretty enough setup to stay under radar.

You can't get "burner" SIMs in Australia (where I am), I don't think. They usually require a sign up before activation; I'd be interested to know of ones that are true "burner" SIMs that are sold here.

Oh, you definitely can. You're just unlikely to be able to find them without already being involved in crime

Re: Hong Kong protestors using Bridgefy's Bluetooth-based mesh network messaging app

#80

I just tried the app via the US App Store and it requires you to verify through SMS before use. This means that it’s neither anonymous nor fit for use in a disaster zone. Good example of software that would be better if open source.

Is there any software that would be worse when open source?
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