Point-to-point Wi-Fi bridging between buildings–the cheap and easy way
arstechnica.com
arstechnica.com
For the curious: https://www.reddit.com/r/homelab/comments/j4y4f4/my_21km_p2p...
The LDF [1] in particular is intriguing -- it is "meant to be installed on satellite offset dish antennas" i.e. you can re-use a (potentially already installed) dish antenna as a reflector.
Configuring these devices is not exactly intuitive though.
Documentation often gives radio performance values for different encodings, e.g. the Mikrotik DISC Lite5 gives Tx and Rx specs starting from 6Mbps (essentially 802.11a) up to MCS9 (256 QAM) which can do well over a gigabit. We can do some naive calculations to estimate that MCS9 is achievable at up to 5km (really pushing it) while 6Mbps works out to 50km or more! In practice there are other factors that will limit these because you start getting into fresnel zones and such, especially as you get over a few km.
The Ubiquiti devices are a bit more expensive but are easier to work with than Mikrotik. They also have higher-end options available for very long range use, 50-100km type scenarios, although the data rate gets very low.
On the shorter end of things tho lol mikrotiks new app make setup as pleb as ubiquiti if you need that level of simplicity. Devices cost about 1/3rd too. I don't sell anything else for WiFi or networking unless you need >10gb mmwave....which you don't.
Main thing is mount them high up and you need some protective enclosures.
I ran a SWA (steel wire armoured) power cable down too in an earlier project and have four double IP66 (EU regs for water and dust ingress - 66 is good for an accidental spray from a hose)
My garden backs onto a park and my summerhouse has a POE switch with an AP in it. I can get wifi in the park to quite a long range. I also have a DECT extender in the summerhouse. The range I can use my house phones (I have an IP PBX) is pretty mad.
I found the user-contributed installation hints to be helpful:
https://arstechnica.com/gadgets/2021/08/point-to-point-wi-fi...
Uhhhh, well; 900mhz would be better if you need penetration.
As for range, the higher the frequency, the narrower the fresnel lenses and therefore the better the range you get without tall towers.
What makes 2.4 particularly usable in rural areas is that you’ll have the lowest amount of interference (usually).
What I like about this install is that they’re going through glass, which might even be worse for RF than the barn wall.
https://www.reddit.com/r/networking/comments/5w7yt9/everyone... 100Mb/s seems to be the upper limit of a perfect link? That would be cutting it close for a single family all on zoom/netflix at the same time.
Edit: thought buildings meant like "apartment buildings", not single family residences on both ends
It's incredibly cheap, being mass produced and mature, and it works fine up to a few kilometres. Replacement is so easy and cheap, that it's not worth bothering with lightning arresters and all the rest (except if fire is a major consideration.)
And 2 cheap Asus routers for 400 meters. Would've likely worked for twice that distance.
Iirc the total cost was less than 200 Euros. Pretty cheap and easy, too.
I would have much more interested if they had dug a trench, installed fiber, or hell UTP CAT5 or CAT6. [0] This wasn't a 'tricky' task, you are operating within spec of all network cabling released in the last 20+ years.
As another posted pointed out, 800m would have made for a more interesting story even if it was just buried fiber-optic cabling.
The other part that annoys me is that no foresight for the future was taken into consideration. Let's assume that there are no trees blocking the line-of-site between the two antennas. Will it remain clear and obstruction free for the next 10 years? What about 20? I have a cable conduit installed between my house and my garage. 30'ish feet. That conduit has not had a problem since 1985 when it was installed. The cabling was upgraded from intercom to phone to network CAT5. Being out in the elements will age your equipment.
Future proofing AKA How often do you want to climb up that ladder: Wireless tech has horrible shelf life and is quickly surpassed. Data needs are always increasing. The 1Gb/s switch I installed back in the 2000's can still handle the workload today, but the wireless AP I installed 5 years ago is buckling under the load that it can't accommodate.
This article is as impressive as telling us the story of how they might have upgraded their service from 1Mb/s DSL to 10Mb/s cable.
[0]For twisted-pair Ethernet, maximum cable length is 100 m (Cat-6A for 10GBASE-T, Cat-5e for 1000BASE-T or 100BASE-TX, Cat-3 for 10BASE-T).
#1 - I don't really want an aerial cable running through my back yard, plus it'd have to be pretty high to give enough clearance for the septic pumping truck.
#2 - running cable between the 10th and 13th floor of buildings across the street from each other would require permission from both building owners, and maybe a permit from the city too. While a wifi link just sits in the windows on each side.
I still have fiber above ground running through my yard. ATT doesn't bury it, they just run it above ground and wait for a 3rd party contractor to come by and bury it later. Mines been above ground for 6 months now
> The good news is, with the right gear, you can connect your home to an outbuilding without either professional expertise or a ditch witch and a spool of burial-grade cable.
> Our goal in this exercise is not to geek out as hard as possible by mounting and aiming everything with millimeter precision. Instead, we're simply out to demonstrate that wirelessly connecting two buildings quickly, cheaply, and easily is possible for anyone. In fact, you can even enjoy more-than-acceptable results in the end.
> When you want to extend a network from one building to another, the best answer is almost always a cable—preferably a burial-grade cable, either Ethernet or fiber, laid in a conduit and buried several feet underground. But that's expensive. If all you need is good Internet access in a nearby pool house or barn, it's almost certainly overkill.
A low-effort, low-cost, low-commitment solution is sometimes all you need.
1) Radios do have a relatively short life, even with proper carrier grade STP cabling and surge protectors. ESD damage from t-storms will inevitably take its toll on them. Usually though, either you can get them replaced under warranty, or at least get a better/faster replacement (although you have to upgrade both ends).
2) It's not a good idea to run any kind of wires between buildings that have separate electrical systems / different ground potential (an outbuilding with a sub panel is fine). I've seen differences in ground potential of 12-15V or more measured between the drain/ground wire and the building ground (this can also varies daily based on the moisture levels around the buildings). Ethernet does use differential signaling, so it's "mostly ok" if you're under 100m. But again the bigger issue is that ESD from t-storms will cause damage to switches (even STP cable grounded at one end) with long runs of ethernet. YMMV with a metal conduit, or with proper surge protection where the cable enters the building. You'll also need (expensive!) carrier grade shielded twisted pair with the drain wire and UV resistant if it's in the sun as well as shielded ethernet jacks for each end (well, you should probably only ground one end).
3) TBH, Fiber is where it's for building to building if you can do it. Most decent switches these days have one or more SFP ports and you can get a pair of Gigibit SFP transceivers for ~$15. Multimode fiber is pretty cheap too -- you can get custom lengths, armored etc. the hard part is the trenching/conduit! But if you're going to go to the trouble of digging a trench and running conduit then put fiber in it, don't bother with ethernet!