Point-to-Point Wireless Bridges: Getting Internet to a Barn, Shop or Second Building

If you've got a detached garage, a shop, a barn or a guest house that needs internet, you have two options. You can trench a cable out to it, or you can put a radio on each building and beam the connection across. That second option is a point-to-point wireless bridge, and I've been setting them up and making videos about them for years. Done right, a wireless bridge just works and you forget it's there. Done wrong, it drops every time the wind blows.

How a wireless bridge works

You mount one radio on the building that already has internet and a matching radio on the building that doesn't. The two radios point at each other and form a link, and as far as your network is concerned, it's just a really long Ethernet cable. Plug a switch or an access point into the far radio and the outbuilding is on your network.

One radio is set up as the access point and the other as the station. If you need to feed more than one building, a single access point radio can serve several stations. That's point-to-multipoint (PtMP), and it's how you'd cover a shop and a guest house from the same house-mounted radio.

Line of sight comes first

Before you buy anything, stand where the first radio will go and look at where the second one will go. If you can see it clearly, you're in good shape. Trees, hills and other buildings are the problem, and they're the reason most links underperform.

It isn't just the straight line between the two radios, either. The signal spreads out into a football-shaped zone between them (the Fresnel zone). If the middle of that zone is full of tree branches, the link will be slower and less stable than the numbers on the box. Mounting higher usually fixes more than buying a bigger radio does.

Can you go through trees? Not dense ones. Even 2.4GHz won't make it through a thick stand of trees. Line of sight is always best.

Picking the gear

These are the Ubiquiti options I've used and covered on the channel:

• UISP Wave and the UniFi Building Bridge. These are 60GHz radios with a 5GHz backup radio built in, and they move a lot of data (1+ gigabit on the Wave lineup). 60GHz needs a clean line of sight and works best at shorter distances. The Building Bridge comes as a pre-configured pair, which makes it the simplest option for linking two buildings on one property.
• airMAX NanoBeam 5AC. These are 5GHz radios and my go-to for a long time. They reach farther than 60GHz and are more forgiving, at lower top speeds. My step-by-step setup video uses a pair of these for both point-to-point and point-to-multipoint.
• UniFi Device Bridge Pro. It picks up the Wi-Fi mesh signal from your UniFi access points to connect a wired device or a small outbuilding. It's a good fit when you already run UniFi and the outbuilding isn't far. I used a UDB Pro to link a main house to a back unit on a ranch property.

Pick the gear for the distance you actually have and the obstacles in the way, not the maximum range on the box. A link across a field and a link to the garage call for very different radios.

Mounting, power and protection

• Both radios are powered over Ethernet (PoE). Check that your switch or injector puts out the right kind of PoE for the radio you bought. Mismatched PoE is a common reason a radio won't power up.
• Mount solidly. A pole that sways in the wind will knock a narrow-beam link out of alignment.
• Put a surge protector on the cable run at each end. A long outdoor cable is an antenna for lightning.
• Use outdoor-rated gear outdoors. I recently looked at a beach club install that was mostly done well but used indoor equipment outside, and that's asking for trouble.

Aiming and setup

Configure both radios on the bench before you climb a ladder. Once they're mounted, aim them using the signal readout in the radio's interface, making small adjustments on one end at a time, and lock them down when the signal peaks. When the link is up, run a speed test across it and save a backup of each radio's configuration. If a radio ever gets reset, that backup turns an afternoon of reconfiguring into a few minutes.

Want to try it yourself?

These videos walk through the whole process, from planning to aiming.