Reticulum is a radio protocol for a mesh network. Encrypted peer-to-peer communication without internet

As we discussed earlier, turning off the Internet in a particular country or city is not a fictional threat, but a completely realizable action. In particular, the international association Internet Society recorded in 2021 49 artificially triggered shutdowns.

But there are effective technologies that will allow you to survive a possible shutdown. For example, mesh networks for radio communications.


One of the latest developments in this area is Reticulum network stack (RNS).

To date, many fragmented solutions and specialized tools have been created, but so far there has not been a complete communication stack for a mesh network that ordinary users can raise without any central coordination. The RNS developer tried to fill this gap.

Such a network can be deployed in half an hour in the event of a systemic communication failure in a particular area or around the world. No drivers or kernel modules required for embedded OSes. The network stack is easy to install on any radio modem, and this operation does not require special experience with computers or radio transmitters (full documentation, pdf).

RNS is based on a completely new protocol that has several advantages over the IP protocol (although IP is also supported).

The main advantages of Reticulum over traditional network stacks are support for very low bitrates and very high latency. That is, it is possible to transmit packets over the simplest radio channels during short-term communication sessions. At the same time, end-to-end encryption and complete anonymity are preserved.

Stack Features

• Non-coordinate global addressing and identification.
  
• Fully self-configuring multi-hop routing.
  
• X25519 asymmetric encryption and Ed25519 signatures.
  
• Encryption specification Fernet:
  

  • AES-128 in CBC mode with PKCS7 padding;
    
  • HMAC with SHA256 authentication;
    
  • generating initialization vectors with os.urandom();
    
  • Forward Secrecy with Ephemeral Elliptic Curve Diffie-Hellman (ECDH) Keys Curve25519.

• Tamper-proof package delivery confirmations.
  
• Variety of interface types.
  
• Intuitive and easy to use API.
  
• Reliable and efficient transmission of arbitrary amounts of data.
  

  • support for multi-gigabyte files;
    
  • automatic calculation of checksums, coordination and restoration of the sequence of packets;
    
  • extensible request/response mechanism.

• Efficient connection establishment: three packets with a total size of 237 bytes, then a connection maintenance cost of 0.62 bits per second.

Network Stack Developer −

Mark Quist

, an experienced developer and network engineer who has spent his entire life creating and managing computer networks. Owner of company

Unsigned.io

which develops and sells

equipment

for radio communication (modules

RNode

modems

micromodem

and

openmodem

).

Reticulum can run on almost any device, starting with the tiny Raspberry Pi Zero. With Reticulum, people with minimal telecommunications and computer knowledge can raise a long-distance messaging system for their community, Quist says.

For example, you can easily raise a mesh network inside the city and establish a communication channel with a neighboring city via VHF, He speaks Quist: “If you already have a modem and a radio transmitter, it will take five minutes to set up. I really tried to make the stack as flexible as possible, yet very easy to use for people with minimal experience with computers and radio transmitters.”

How it looks in practice, you can see the example Nomad Network. This is a prototype of a stable mesh network based on protocols LXMF and Reticulum.

Devices on the Nomad Network

This project is fundamentally different from many other mesh networking projects in the world, such as a public city network NYC Mesh. All of them aim to eventually access the Internet. And here, a network separate from the Internet is initially created, and even with strong encryption. This is a fundamentally different level. In fact, Reticulum supports the full apocalypse scenario.

“Reticulum is an attempt to create an alternative base layer protocol for data networks,” He speaks author. – In fact, this is not one network, but a tool for building networks. It can be compared to IP, the Internet Protocol stack that powers the Internet and 99.99% of all other networks on Earth. It solves the same problems as the IP stack, providing digital data transfer from point A to point B, but it does it in a completely different way and with completely different assumptions. The real strength of the protocol is that it can take all kinds of different means of communication and connect them into a single network. He can use [дальние] transceivers, modems, radios, Ethernet, WiFi, or even a skein of old copper wire if you can.”

Encrypted messaging on the Nomad Network radio network

The development of Reticulum is still in its infancy. The program code has not been audited for encryption security. That is, in reality, it is still too early to use it in a serious matter.

The problem is that all existing network software is written for the IP protocol. Therefore, for the network stack, Reticulum will also have to create a new software stack: existing programs will not work there. Although something has already been developed. For example, messenger sideband (Android, Linux, MacOS) for text messaging over LoRa, packet radio, WiFi, I2P, or any other transport protocol supported by the peer-to-peer communications stack LXMF.