
HK protesters use “unblockable” messaging via a bluetooth mesh - gumby
https://www.bbc.com/news/technology-49565587
======
rcw4256
Previous discussion
[https://news.ycombinator.com/item?id=20861948](https://news.ycombinator.com/item?id=20861948)

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ngcc_hk
“Be water my friends” said bruce lee. It is not one or two or three trial. It
is one of the attempts.

The problem is hard as police is using various tactics to try to silence
protestors. As mentioned they “can join and hone in on”. And once found
physical protestors, they can beaten them up and then if circumstances allow,
they could charge them as beaten up police instead etc. So far 1000+ arrest
and as you seen many protestors are hurt - 4 eyes are lost ... etc.

The leaderless communities have to work out how to communicate. This is one of
the attempts as LIHKG is ddosed during protest time. No doubt, they will try
others. We will try until the five demands are met. (The last one is for the
real elections as promised in joint declaration and basic laws.)

Hong Kong Add Oil.

Human fighting for liberty should not perish from the earth.

~~~
dmix
I'm guessing HK police haven't adopted body cams yet?

For that matter, has anyone outside of North America?

~~~
captn3m0
Bangalore police in India spent some money in acquiring them but looks like it
was lost to corruption.

~~~
captn3m0
Report: [https://bangaloremirror.indiatimes.com/bangalore/cover-
story...](https://bangaloremirror.indiatimes.com/bangalore/cover-
story/bengaluru-traffc-police-wasted-rs-75-lakh-and-nobody-recorded-
it/articleshow/71000909.cms)

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aussieguy1234
The SMS verification in this app makes it insecure. The Chinese govt could
easily see who has the app based on this. They can probably assume anyone who
has the app installed is a protester

~~~
dmix
At a minimum it would be a signal. I remember from the Snowden leaks that NSA
was monitoring people who had searched for Tor Browser and other privacy
tools.

~~~
enkid
Do you have a source for that?

~~~
dmix
[https://www.wired.com/2014/07/nsa-targets-users-of-
privacy-s...](https://www.wired.com/2014/07/nsa-targets-users-of-privacy-
services/)

[https://www.cnet.com/news/nsa-likely-targets-anybody-whos-
to...](https://www.cnet.com/news/nsa-likely-targets-anybody-whos-tor-curious/)

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antpls
Oppo released a similar app few month ago :
[https://venturebeat.com/2019/06/26/oppos-meshtalk-
technology...](https://venturebeat.com/2019/06/26/oppos-meshtalk-technology-
lets-phones-exchange-data-up-to-3-kilometers-without-wi-fi-bluetooth-or-
cellular-connectivity/)

~~~
dear
Oppo is a chinese company. What are they trying to do with an app like that?

~~~
zoom6628
These sort of apps great for indoor events, crowded+huge shopping malls,
concerts, clubs.....I will be generous and say those are the sort of targets
for Oppo app. Not met anyone using it yet.

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ThinkBeat
With the very short range of Bluetooth you would have to have massive adoption
to carry the signal any distance. With a crowd or protest or sports arena I
can see it but to send messages to someone quite a ways away it would not
work. So good for masses and coordination within them.

~~~
nbanks
With Hong Kong's population density, I could see this technology working
fairly well. I'm not sure how well it would work inside buildings, but could
be good enough for people walking on the streets. It would also theoretically
possible for each phone to store hundreds of encrypted text messages if
latency isn't important.

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squarefoot
Here's an idea I came with at least 8 years ago and wanted to develop further
but in the end never managed to. I'm not aware if someone in the meantime made
something like that, however this article brought it back to mind.

Basically it was a phone app that through mesh networking (Bt/WiFi) builds
then maintains updated a distributed database of signed up local devices where
each record contains accurate geographical coordinates (or seat numbers in
public places - that would require a map of course) of all devices then
arranges them in a xy matrix, rounding to the next available device when
necessary. The initial purpose of the app, once the owner wears it like a
pendant, was to make each device screen become essentially a RGB pixel in a
giant screen, then distribute and synchronize (again, through mesh networking)
down to fractions of a second (NTP and GPS should allow that) both graphical
and temporal data to drive them. My idea was to use this giant screen to allow
people to show political dissent messages in countries/times/places where this
is not permitted (just imagine a 20k people crowd in a stadium). The app
should have implemented some mechanism so that only trusted people could
decide and schedule what's being shown and when, but other than that, every
connection would have been on a peer to peer basis through mesh networking. I
didn't think about implementing a chat over all the above, but that would
probably be a lot simpler than the rest. As further security measure, the
database should be encrypted so that if someone is arrested it won't reveal
the peers data/position, and a panic button or dead man switch function could
also be added so that a routine propagates the alert instructing all other
apps to uninstall themselves and reboot.

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rolltiide
Remember the last time HK protesters were using mesh networking via an app in
2014? Something like FireChat or something

Anyway, funny how this is still novel news and there is no market leader in
this space, because that was 5, almost 6 years ago.

~~~
swiley
The problem is that the popular mobile OSes make a lot of this stuff harder
than it needs to be. Maybe if it ended up in the IEEE standard...

I still feel like ad-hoc wifi networks with something like BGP would be
better. On the other hand there still isn't a good standard "chat over IP"
except maybe unix "talk" which just about no one uses.

~~~
Nextgrid
SIP can work point-to-point directly over IP without a central server. I
remember trying that with 2 SIP phones connected directly via Ethernet
(configured with static Its) and I could call the IP of the other phone and
that one would ring.

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ReptileMan
Since Bluetooth is trivial to be disruped (or wifi for that matter) couple of
programmers with enough sdr s and antennas could block it in a weekend...

~~~
markus92
Not that trivial with the huge amount of frequency hopping it does, or is it?

~~~
loeg
It does not hop outside of the defined unlicensed[1] 2.40-2.48 GHz band. If
you can block that whole band, BT doesn't work.

[1]: In the US; it's complicated. Tl;dr is [http://afar.net/tutorials/fcc-
rules/](http://afar.net/tutorials/fcc-rules/) , much much more verbose is
[https://www.ecfr.gov/cgi-
bin/retrieveECFR?mc=true&r=PART&n=p...](https://www.ecfr.gov/cgi-
bin/retrieveECFR?mc=true&r=PART&n=pt47.1.15)

~~~
zoom6628
2.4GHz band is the GSM band here in HK so would be major disruption of general
communications which is why they cant do it. Yes GSM runs on other bands like
1900 but majority of phones in Asia use GSM as backbone, and LTE over this
freq, so unadvisable to block that freq. What could be done is to flood the
mesh from myriad devices running the same app or derivative.

~~~
elmicha
I can't find 2.4GHz as a GSM band:
[https://www.spectrummonitoring.com/frequencies/frequencies3....](https://www.spectrummonitoring.com/frequencies/frequencies3.html#HongKong),
[https://m.gsmarena.com/network-
bands.php3?sCountry=HONG+KONG](https://m.gsmarena.com/network-
bands.php3?sCountry=HONG+KONG),
[https://www.frequencycheck.com/countries/hong-
kong](https://www.frequencycheck.com/countries/hong-kong)

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StringyBob
I downloaded Berkanan for iOS this summer for use at music festivals when
mobile network capacity usually fails, but I didn’t get a chance to use it -
anyone else tried it?

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yumraj
Well, I'm sure if this catches on more, China will ask respective App stores
to block this app.

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marrone12
Yes, I don't know how they can call it unblockable, since it's quite easy to
block apps from app stores.

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app4soft
Government can't block apps that could be transferred from one device to
another via Bluetooth/WiFi. iOS/Apple devices are bad in this case; Android
would be much better choice for organizing such meshes.

Also, F-Droid.org is safe place for Android users.

~~~
snazz
F-Droid includes a feature to get apps over Bluetooth.

~~~
29083011397778
I did a quick search for the app named in the article when it was first posted
and didn't see it listed on F-Droid. I was actually surprised the protesters
were using something closed-source.

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Aloha
This looks cool

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einpoklum
Why doesn't that app just create the mesh network, so that existing chat apps
(Telegram, Signal) can be used on it?

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jethro_tell
Dont telegram and signal use centralized servers?

You need both a mesh net and a p2p chat app which single and telegram are not.

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dTal
With such fractured connectivity, there's probably not much benefit in trying
to abstract away the foibles of the network topology from the chat
application. An ideal system would merge the network and application layers
for the greatest reliability, at the expense of generality (but then a
fractured meshnet is not a very general platform to begin with).

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tgsovlerkhgsel
This is a classic use case for store-and-forward. Trying to build a mesh where
sender and recipient need a TCP-style connection is futile; store and forward,
on the other hand, would be ideal for Twitter-style applications.

~~~
dTal
That was basically what I was trying to get at, but your comment was much
better and more succinct.

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DaniloDias
1) why use bridgify instead of goTenna mesh? Never heard of bridgify
previously.

2) [https://bridgify.io/](https://bridgify.io/). First part of the page is
dedicated to fundraising.

Is this link fake news?

~~~
detaro
1) Because few people own a goTenna device, whereas nearly all smartphones do
Bluetooth?

2) Your link is an entirely different company, with a different name...

Some diligence please before throwing accusations around.

~~~
DaniloDias
Thanks for catching the link problem. Is there an authoritative site you can
point to?

Is this it?
[https://www.bridgefy.me/?ref=producthunt](https://www.bridgefy.me/?ref=producthunt)

~~~
detaro
Yep, that's the company. That's the specific site for the app:
[http://www.bfy.buzz/](http://www.bfy.buzz/), which mostly seems to be
intended to show that the tech they want to sell works.

