A Mesh Network (or Meshnet) is a type of network architecture where each computer is connected to neighboring computers, usually via Wi-Fi. Mesh Networks have a self-healing capability — they continue to work even if participating computers drop out. As a result, the network is typically quite reliable and cannot be easily shut down, as there is often more than one path between a source and a destination in the network.
Although Mesh Networks can take many forms, the most promising examples are Wireless Mesh Networks, which are built using long-range Wi-Fi routers. With this design, there is no need for an Internet Services Provider (ISP). In fact, Mesh networks are also being used to provide basic connectivity to people around the world who do not have access to conventional ISPs.
Mesh Networks are already being used on college campuses and in corporate complexes. Military systems rely on mesh networking, since forces in the field cannot rely on communications infrastructures. Utilities also use mesh networks for collecting data from equipment, like smart meters. You can read about some existing Mesh Networks here. The largest public Wireless Mesh Network in the U.S. is the Seattle Meshnet. Another large project in the works is Project Meshnet, which is currently involved in building a Meshnet called Hyperboria.
Mesh networks can also be used with mobile device, where they are called MANETs or Mobile Ad Hoc Networks. If you’re in your home next to a Wi-Fi router, you might have a clean signal and access to a 12-megabit connection. Meanwhile, someone outside your door could have a smartphone that’s struggling to hold onto a slow connection to a cellular tower a mile away. But mesh networking might make things better for everyone.
Mesh networks let devices share their connections with other users. If one user has a clean network connection and another nearby user does not, the second user can piggyback on the first’s, automatically. If there’s a collection of many people, their machines can all cooperate to make connections — to each other and to the global Internet. In advanced mesh networks, connections and data can hop among devices, creating ad hoc bucket-brigade paths for communication.