Reticulum is a cryptography-based networking stack for low-bandwidth, high-latency, wide-area networks built on cheap and readily available hardware. Reticulum allows you to build very wide-area networks with cheap off-the-shelf tools, and offers end-to-end encryption, autoconfiguring cryptographically backed multi-hop transport, efficient addressing, resource caching, unforgeable packet acknowledgements and much more.
Reticulum is a complete networking stack, and does not use IP or higher layers, although it can be easily tunnelled through conventional IP networks. This frees up a lot of overhead, that has been utilised to implement a networking stack built directly on cryptographic principles, allowing resilience and stable functionality in open and trustless networks.
Practically any hardware that can support at least a half-duplex channel with 1.000 bits per second throughput, and an MTU of 500 bytes. Data radios, modems, LoRa radios, serial lines, AX.25 TNCs, HAM radio digital modes, free-space optical links and similar systems are all examples of the types of interfaces Reticulum was designed for.
An open-source LoRa-based interface called [RNode](https://unsigned.io/projects/rnode/) has been designed specifically for use with Reticulum. It is easy to build yourself, or can be purchased as a complete radio that just needs a USB connection to the host.
Reticulum can also be tunneled over existing IP networks, so there's nothing stopping you from using it over gigabit fiber or your local WiFi network, where it'll work just as well. In fact, one of the strengths of Reticulum is how easily it allows you to connect different mediums into a self-configuring, resilient and encrypted mesh.
As an example, it's possible to set up a Raspberry Pi connected to both a LoRa radio, a packet radio TNC and your home WiFi. Once the interfaces are configured, Reticulum will take care of the rest, and any device on your home WiFi can communicate with nodes on the LoRa and packet radio sides of the network.
Consider Reticulum experimental at this stage. Most features are implemented and working, but at this point the protocol may still change significantly, and is made publicly available for development collaboration, previewing and testing.
Some countries still ban the use of encryption when operating under an amateur radio license. Reticulum offers several encryptionless modes, while still using cryptographic principles for station verification, link establishment, data integrity verification, acknowledgements and routing. It is therefore perfectly possible to include Reticulum in amateur radio use, even if your country bans encryption.
Full documentation and video tutorials are coming with the stable alpha release. Until then, you are mostly on your own. If you really want to experiment already, you could take a look in the "Examples" folder, for some well-documented example programs. Be sure to also read the [Reticulum Overview Document](http://unsigned.io/wp-content/uploads/2018/04/Reticulum_Overview_v0.4.pdf).
The default config file contains examples for using Reticulum with LoRa transceivers (specifically [RNode](https://unsigned.io/projects/rnode/)), packet radio TNCs/modems and UDP. By default a UDP interface is already enabled in the default config, which will enable Reticulum communication in your local ethernet broadcast domain.
You can use the examples in the config file to expand communication over other mediums such as packet radio or LoRa, or over fast IP links using the UDP interface. I'll add in-depth tutorials and explanations on these topics later. For now, the included examples will hopefully be enough to get started.
Reticulum is alpha software, and should be considered experimental. While it has been built with cryptography best-practices very foremost in mind, it _has not_ been externally security audited, and there could very well be privacy-breaking bugs. If you want to help out, or help sponsor an audit, please do get in touch.