One Maker Turned Cheap Radio Boards into a Private Mesh Network That Crosses Oceans

Data Slayer wondered if it was possible to send messages across large distances without relying on those giant telecoms providers, and for him, the answer was definitely yes. He accomplished the feat of bridging the almost 2,500-mile gap between Florida and Venezuela to demonstrate his idea. Even more impressive, though, is that he accomplished this using just about 20 radio boards (which cost between $20 and $30 apiece), a few small computers, and some open-source networking magic known as Reticulum.

It all began in a typical home with thick walls, the kind of site where signal strength issues are likely to arise. Using a unique kind of Wi-Fi that is intended to reach a little farther, one of the tiny computers running some modified software was able to maintain a local network. There was almost no trouble sending messages from one room to another; text messages appeared extremely immediately, voice notes worked well, and even photos were sent. Alright, so it was performing better than anticipated, but he wasn’t happy about it. He want more separation.

In order to see the signal spread out throughout the neighborhood, about 2,000 feet away, he grabbed a portable version, brought it outside, and threw it over a car. Even with the assistance of a few basic antennas, the signal strength was still reduced by those thick walls.

He then moved on to a different kind of radio board that was based on LoRa technology since, although Wi-Fi would function well for short hops, it wasn’t designed for long distances. He adjusted the settings (narrow bandwidth, high spreading factor, error correction, etc.) to establish steady connections over three and a half miles because these boards use frequencies that can push through interference and go very far. Elevation obviously made a major difference. When the weather was favorable, he would hack the nodes onto a drone or a kite to gain a clean view above all the barriers.

Reticulum is in the center of it all. All of this is made possible by the software, which simply routes data independent of the type of wire or wireless you’re using. Everything is secured from beginning to end, whether a board is communicating with another board or a phone is connecting through an app. Although devices can differ (one may use LoRa while another uses standard Wi-Fi) everything works together seamlessly. Mesh Chat is for PCs, and Sideband is for Android, but once everything is configured, traffic just…works. There are just a number of disparate devices communicating with one another and going about their daily business without the need for specialized drivers or compatible hardware.

One more step is needed to keep it all under wraps when relocating abroad. Thanks to other trailblazing builders, local meshes were already in place in Florida and Venezuela. Using pre-existing internet infrastructure, Data Slayer was able to establish a temporary encrypted tunnel between the two organizations. Since the actual messages are entirely encrypted, the public network is oblivious of them. The response appears a few seconds after a person in Florida opens Sideband and inputs a message to someone in Venezuela. The network can handle much more than just basic messages, and tests have even used mapping software intended to keep teams in sync.

The prices are consistently cheap enough for almost anyone with a little curiosity to try this. The maximum cost of twenty radio boards is about $500. The overall cost is less than $1,000 with a couple Raspberry Pi devices and some simple antennas. Massive towers and licensed frequencies are not necessary at all. Small batteries or a wall outlet provide power. The nodes may sit outside all day without attracting any attention because they operate silently and consume very little electricity.
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