In the event of a complete disconnection of the Internet, one of the main problems is communication with friends and relatives. Hong Kong’s experience shows that decentralized P2P messengers that work without the Internet using mesh network Wi-Fi Direct, Bluetooth, Apple Multipeer Connectivity Framework, ANT +, LoRa, etc.

For effective communication, the application must be downloaded by the maximum number of people before the beginning of the blockade of the Internet. Otherwise, you will have to search for files after the blockade. A person with the necessary files will become a real authority in the office or in the classroom (as it was in Belarus in August 2020 – people actually came to get Psiphon files from other micro-districts of the city).

In general, the entire history of wireless mesh networks hints that this technology is extremely disliked by law enforcement agencies.

Mesh networks

Apps like FireChat create a mesh network using Bluetooth and direct connections over Wi-Fi. They provide the exchange of messages and photos offline between devices located at a distance of about 60 meters from each other.

All users form a single network, which expands with the increase in the number of devices. On the way to the recipient (s), messages are passed from one device to another.

In other words, you just need to get 60 meters closer to the nearest user – and you can send a message to anyone. Each user is a node on the network. Without Internet.

Therefore, the more people use the application, the larger the network, and the better it works. By the way, this is the fundamental difference between mesh systems and most other computer networks and network technologies, including cellular networks.

If any node of the mesh network suddenly goes online, then messages in a packet from all users will go to recipients all over the world.

It is especially convenient if channels or rooms in the messenger are created automatically and unite people who are next to each other (apartment building, stadium, concert hall).

Almost any mesh network can be adapted to transfer text messages, even a network of Apple AirTag geotags, which are actually not intended for communication between people, but for finding lost things. In May 2021, hackers managed to decrypt AirTag traffic and send arbitrary text over the Apple Find My network under the guise of original encrypted messages with GPS coordinates. The transfer rate was 3 bytes per second. Network latency – from 1 to 60 minutes.

Samsung (Smart Things) and Amazon (Sidewalk) also have similar mesh networks using the LoRa protocol. In principle, this infrastructure can be used for peer-to-peer messaging, as well as for retrieving data from devices outside the Internet access zone.

Tragedy FireСhat

FireChat is a proprietary application from an American company Open garden… This firm stopped further development without opening the source…

Latest app version: 9.0.14 (copy on w3bsit3-dns.com) came out a year and a half ago (note: access to the w3bsit3-dns.com website is difficult from the territory of the Russian Federation).

FireChat

The first version of FireChat appeared in March 2014 for iOS, in April – for Android. Among the co-founders of Open Garden and the developers of the program are Stanislav Shalunov and Greg Hazel from BitTorrent, where they made the uTorrent torrent client (200 million users). There we met.

The entrepreneurs probably hoped that FireChat would become as successful as P2P file-sharing applications. If you imagine this picture, then the whole world can be united into a mesh network, and the Internet becomes practically unnecessary! Even website hosting can theoretically be smeared across a distributed network. Such a fantasy.

Very fast FireСhat gained popularity in Iraq after the local government imposed restrictions on internet use and then the same thing happened in Hong Kong, during the mass protests of 2014…

The main problem of FireChat during the mass protests in Hong Kong was security. The very architecture of an open mesh network assumes that all users of the application “shine” like radio beacons at a distance of 60 meters, or even more. So it was very easy for the police to catch them. The presence of the program on the phone clearly proved guilt. It can be assumed that hundreds or thousands of users were arrested thanks to FireChat. In addition, no encryption was used in the applicationso no messages were really private.

Perhaps criticism from information security specialists influenced the decision of the American company Open Garden to stop development and not publish the source code. Well, or the guys saw that the worldwide popularity of torrents did not shine for them, and the development of the program went completely the wrong way.

When FireСhat appeared, it was the only program of its kind that allowed users to create mesh networks offline (without the Internet) and exchange messages^one…

The tool, which was conceived for the communication of people, has de facto turned into a tip for repression and physical violence. Perhaps there is some kind of tragedy in this.

Photo from article “FireChat is the messenger running the protests in Hong Kong”, The Guardian

It is all the more offensive if FireСhat was created specifically for Hong Kong, like the development of a similar Commotion Wireless application in 2011 funded by the US State Department ahead of the Arab Spring… We wanted the best, but it turned out as always …

After FireСhat, Open Garden traded electronic SIM cards (eSIM), promoted its cryptocurrency, but in recent years nothing has been heard about her.

In general, the FireChat application was not very high quality. First, it’s closed source. Secondly, for registration it was necessary (!) To need access to the Internet, although later it worked offline. In short, a strange program. Maybe it’s good that the developers buried her.

Walkie Talkie Zello

The Internet walkie-talkie is similar in terms of the logic of its functioning. Zello, which is blocked in the Russian Federation in April 2017.

The radio works on the principle of walkie-talkie or push-to-talk. The main advantage is the ability to listen to voice messages over the speakerphone in real time, without touching the smartphone at all, and at the same time be in touch with a large number of users.

Although not text / pictures are transmitted here, but sound, the principle of operation is the same – via a mesh network, without the Internet. Close to each other users connect with each other directly and transmit messages further along the chain. Importantly, it uses end-to-end encryption (E2E).

In Russia, the application has gained particular popularity among truckers and other motorists, since it is very convenient (and pleasant) to talk with fellow travelers who are driving along the same highway. They will tell you about the radar in the bushes, about an accident on the road, etc. Repression by the state began after the massive protests of truckers in connection with the introduction of a mandatory payment to billionaire Igor Rotenberg for the passage of heavy trucks on the roads of Russia (system “Plato”). The protests were coordinated through Zello, so they decided to block the program.

This was the first time the authorities tried to break a VPN messenger. It took a full year to block over 4,000 IP addresses from the AWS Cloud, which was unsuccessful. Then RKN went to blackmail Amazon, threatening to block 26 AWS subnets, in the amount of 13.5 million addresses.

Amazon was not ready for war – and refused to provide Zello services. The service, which had lost its cloud infrastructure, was easily blocked.

Following the success of blocking Zello’s cloud-based VPN infrastructure, the authorities decided in 2018 that they could successfully block the same cloud-based infrastructure of the Telegram messenger. But here I found a scythe on a stone: Pavel Durov invested millions of dollars in the purchase of more and more AWS instances, his brother Nikolai and his colleagues programmed a proxy blocking bypass system, and Amazon and Google withstood the blocking of their subnets in the Russian Federation. As a result, the authorities had to block 18 million AWS and Google Cloud IP addresses, which disrupted the work of large retail companies, top 20 banks, private clinics and thousands of businesses in Russia. After two years of exhausting struggle, the state surrendered: the head of Roskomnadzor was fired, Telegram was unblocked, and the IP addresses of cloud services were removed from the black list.

Crypto messenger Briar

Four years ago, in July 2017, the first public beta version of the messenger has been released Briarthat works over Tor or offline, through peering. Its development continued already three years… But the product came out extremely high quality.

This is already honest open source… The application can be compiled from source (step-by-step instruction for Android Studio). It is available in app catalogs (for example, Google play) and is perfectly supported: the latest version 1.2.20 dated April 2, 2021. Implemented strong cryptography, end-to-end encryption.

By default, the messenger works over the Internet using the Tor protocol (onion routing). In this case, the program creates a hidden Tor service on the user’s device and connects to the hidden Tor services of other people from the contact list. In the absence of the Internet, it switches to peer-to-peer communication via Wi-Fi Direct, local area network or Bluetooth.

Of course, when registering with a crypto messenger, you do not need to provide a phone number.

Supports posting (but not files), private groups, blogs / statuses, and RSS imports. There are several useful features such as an application lock (by PIN).

The system is relatively protected from outsiders: new contacts are added via a QR code from another phone (assuming the physical presence of a person) or through the exchange of contacts, or via a unique link. Thus, a person with whom no one is familiar should not get into contacts.

Briar Project is a non-profit project that is currently underway six volunteers… 97.7% of the code is written in Java (+ some Kotlin, Python and Ruby) and is shipped under GPLv3. Shortly after the first release the code has passed an independent security audit from Cure53. She is known for her auditing projects SecureDrop, Cryptocat and Dovecot. So Briar is a really reliable option for peer-to-peer communications.

The only negative is that the app is released Android version only… There is no official version for iOS, and there will not be, because “this platform imposes strict restrictions on developers that do not allow the implementation of some P2P ideas, and is a closed proprietary product.”

But the source code is open source, so theoretically anyone can try to make a third-party implementation of Briar for iOS, for example.

Briar User Guide (in Russian)

Matrix, Riot, Element

Official client Element (formerly Riot) for a relatively decentralized web Matrix not supports peer-to-peer offline communications and mesh network formation.

This client has gained some notoriety lately. Now the number of Matrix / Element users is comparable to Briar or more. It has end-to-end encryption, bridges to IRC, Slack, Telegram, Jitsi Meet, etc. But there is no peering in offline.

See also:
“Secure Scuttlebutt is a p2p social network that works offline” (there is a client Manyverse for Android and iOS)

PS In addition to FireСhat, protesters in Hong Kong used little-known mexican supplement Bridgefy, which also knows how to form a mesh network and transmit messages offline. In October 2020, the application switched to the Signal cryptographic protocol…

^one In fact, there were other applications even earlier, such as Serval Mesh from the project Serval Project or ancient Commotion Wireless from the Open Technology Initiative (funded by the State Department), but all these developments have long been discontinued [вернуться]