Just a few years ago, mesh networks were considered so esoteric that no one would even think of using one unless you had wads of money and a cadre of geeks at your beck and call. The notion of someone using a mesh network to provide rural WiFi on a farm would have been laughable.
Some years back, though, those clever kids at MIT decided they wanted a mesh network across the campus (and beyond) at the lowest possible cost. The result was RoofNet, which eventually gave rise to a commercial offering from Meraki and, later, Open-Mesh and, eventually, AyrMesh. These mesh networks all use low-cost WiFi radios and the internet in clever ways to provide a very flexible WiFi “cloud.”
What’s a mesh network?
A mesh network uses multiple Access Points (called “nodes” or “hubs”) which communicate with each other via wireless links. 
One or more of these nodes may be connected to the Internet; they are usually called “Gateway” nodes. Nodes at the outer edge of the network are referred to as “Leaf” nodes, and nodes between the Gateway and the Leaf nodes are frequently called “Repeaters.”
The major features of a mesh network are:
- Practically unlimited expansion – you can use mesh nodes to extend your network around all kinds of corners: into buildings, around physical obstacles, and, potentially, across large distances
- Simple networking – the mesh can present as a single network, so anything in the network across a broad area can be addressed via its IP address
- Easy maintenance and administration – modern mesh networks like the ones we are discussing here use a central “dashboard” on the internet to manage the nodes, so you never have to go out and “touch” a node (unless it physically fails).
Of course, while a mesh network can be expanded almost arbitrarily, it requires additional mesh nodes to do so. One of the most extraordinary things about the mesh systems mentioned earlier is that the nodes are quite inexpensive – from less than $100 apiece to a few hundred. Besides requiring enormous technical expertise, previous mesh networks cost thousands of dollars per node.
The upshot is that, while mesh networks were previously only for the military and large companies, they are now perfectly suitable for your farm or homestead.
A mesh network of a single node is, essentially, equivalent to a single access point. You connect it to an internet source and turn it on, and it behaves much like a wireless router. The big difference is that you can simply install more nodes to “repeat” or “relay” the signal to different areas: further away and around obstacles to line-of-sight. You can also use those additional nodes to connect “wired” devices into the network by plugging them into the Ethernet ports of the nodes.
This makes the mesh network an extremely useful and practical tool for building your “Farm-Area Network.” A mesh network may not be the “be-all and end-all,” and you may still want to use point-t0-point links and directional clients to expand your network. But I believe that a mesh network on the farmstead is the right place to start.