Tricky network planning across two buildings

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lloydo

New Around Here
Hello SNB gurus, thank you for giving the opportunity to ask for your help.
I want to provide Wi-Fi to my sister's non-profit in Sydney in the most cost effective manner (also so that I won't have to keep going back to support it :)

Goals: range & reliability (high speeds unnecessary)



There are two buildings (luckily single-storey with only a few internal brick walls).
  • The orange squares are offices with printers in them that I'll need to network
  • (A) and (B) denote options for cable internet lead-in from the street (ADSL is at (B) currently)
  • Wi-Fi is desirable in both buildings and in the open garden area where I wrote "23 m"
  • 20 Wi-Fi 5 clients minimum (30 if phones are added)
At first I thought about a daisy-chain "mesh" network (the green splodges) with 1 base and 3 nodes. Ethernet may not be an option here (at least it will be expensive)… I'd prefer wireless if it'll work.

Over the weekend, I've read about dedicated backhaul, 4x4, AC vs. AX, UniFi wireless uplink, but I'm no closer to knowing what to do... Rather than continue with my uninformed guesses, could you please advise how you would plan a network like this?

Cheers
 

thiggins

Mr. Easy
Staff member
You would be best served with a pair of outdoor bridges to connect the two buildings, assuming there are no trees in the way. Depending on mesh to bridge buildings will probably not work, especially at 5 GHz.

EnGenius and Ubiquiti both make products that will work. Search for outdoor wireless bridge.
 

lloydo

New Around Here
Thanks for your advice Tim.

Do bridges require direct line of sight? Because there are a couple of trees and also the white pagoda structure.

I guess I was being optimistic, I thought that 23 metres was doable for Wi-Fi. What if I were to use two of the UniFi AC-M products to create the link? I would also be achieving the goal of coverage for the outdoor area. If 23 m is still too far, could I use the directional antenna UMA-D on the AC-M?

If this is feasible, do you think I could achieve this with Ubiquiti wireless uplink, or is running ethernet between at least some of the points unavoidable?
 

thiggins

Mr. Easy
Staff member
Trees and other obstacles reduce signal level. Depending on distance, device transmit power and desired throughput, you might be ok with a little vegetation between the endpoints, but you'd either have to do calculations or experiment to know for sure. How much bandwidth do you need from the link, anyway? What's your internet service?

The UniFi AC-Ms should be fine and provide the option of trying both bands. You might not want users in the garden area accessing the bridge link, however. Any throughput they use will be taken from the link. If you want the most signal gain you can get, then get the AC-Pros, which are three stream vs. two.

Don't expect either of the AC-M's to provide in-building Wi-Fi, however. Brick walls will reduce the signal level. Install separate APs in each building, set to different channels than the building-to-building link.
 

Trip

Very Senior Member
Would any of the following 5Ghz point-to-point paths work?
layout.jpg

If one of those is interference-free enough, you could use a pair of directional PtP radios to form your link between buildings, wired to upstream PoE switches and then to the rest of the wired infrastructure in each building.
 

coxhaus

Part of the Furniture
If it was me I would run separate networks in each building. Then connect them with fiber either in ground or above ground. This would allow you to run 1 firewall and 1 internet. You would have complete access to equipment in either building without having to cross the internet.

Hire someone to string the fiber.
 

lloydo

New Around Here
Thank you everyone for your responses. I am still thinking and learning.

How much bandwidth do you need from the link, anyway? What's your internet service?
We'll either order a 50/20 or 100/40 service. Bandwidth requirements are not high, the most intensive activity will be uploading photos & videos to cloud.

The UniFi AC-Ms should be fine and provide the option of trying both bands. You might not want users in the garden area accessing the bridge link, however. Any throughput they use will be taken from the link. If you want the most signal gain you can get, then get the AC-Pros, which are three stream vs. two.

I think that is okay. If people in the garden use it, again it will only be for incidental usage.
When you said best signal gain (~range?) do you suggest using AC-Pro facing each other on exterior walls? I have tried to learn about streams but I thought they just increased your available speed not range?
[AC-M plus the antenna UMA-D is not much higher cost than AC-Pro here]

Don't expect either of the AC-M's to provide in-building Wi-Fi, however. Brick walls will reduce the signal level. Install separate APs in each building, set to different channels than the building-to-building link.

Thanks for the advice mate. I'll need to learn about channels soon :)
 

lloydo

New Around Here
Would any of the following 5Ghz point-to-point paths work?
If one of those is interference-free enough, you could use a pair of directional PtP radios to form your link between buildings, wired to upstream PoE switches and then to the rest of the wired infrastructure in each building.
I'll have to go back to check, but yes, I think those paths are okay. Either as Tim says, with AC-M, or a more specialised link. Could you suggest a kit? One which would play nice with Ubiquiti? [The UBB-US is not sold in Australia]

How do you think I would go if most of this equipment is daisy-chained through AC-Pro's 2nd ethernet port (but PoE injected separately)? Then I might not have to buy a switch at all, just use the internet router?
 

thiggins

Mr. Easy
Staff member
If you use the Pros, yes, you would have them face each other on exterior walls since the antennas are directional. The M's would still be mounted outside, but orientation doesn't matter since their antennas are omni directional.

More streams provide higher link rates, but they also increase receive gain, which extends range.
 

ACwifiguy

Occasional Visitor
I’d put the line in the ground between the buildings. Easy to put switches / access points at your green dots to blanket your building. Nothing beats a hard line.
 

Trip

Very Senior Member
On second thought, per @coxhaus's and @ACwifiguy's suggestions, before looking deeper into wireless, what about a fiber run between buildings, either ground or aerial? It's always preferential to go hardwired if you can; wireless only if it's absolutely not doable.
 

lloydo

New Around Here
Thanks everyone, I am coming around to the idea that I can't escape hardwiring. I should be fine to run ethernet that distance though? Fibre seems like another level of cost I'm trying to avoid (as I mentioned earlier, I'm even trying to avoid buying any switches!).

If you use the Pros, yes, you would have them face each other on exterior walls since the antennas are directional. The M's would still be mounted outside, but orientation doesn't matter since their antennas are omni directional.
Thanks mate. Just to be clear, are you talking about UAP-AC-M-PRO when you say it is directional? My understanding was that the UAP-AC-PRO (UFO-shaped) was omni like the rest of the ceiling-mount devices. This page seems to suggest so. I guess it also suggests AC-M and AC-M-PRO are quite omni as well (but with a bias to broadcasting at 60°-120° from vertical).

More streams provide higher link rates, but they also increase receive gain, which extends range.
Ahhh thank you! Learning bits and pieces now :)
 

degrub

Very Senior Member
Consider what it would cost to have two separate internet service drops from the isp. Then , justify what you need to do on that cost savings.

if you don’t bridge between buildings with point to point wireless then use fiber to avoid ground loops burning out hardware due to the difference in voltage of the earth surface at each building.

Does each building have its own electric drop and service meter ? I would assume you are on a system similar to the UK ?
 

Daybreak

Regular Contributor
Howdy,
23 meters = 75 feet
drop some direct burial cat 6 line and be done. Do a ceiling mounted access point at each location.
Fiber =? come on, its a small run. Way over excess for this.
 

degrub

Very Senior Member
i have experience with ground voltage difference burning out correctly installed coax modems with a distance of 40 ft between buildings.

You are correct that it is more of an issue with longer distance runs, usually.

So maybe it works no issue in this case, maybe not.
 

Trip

Very Senior Member
@Daybreak - While fiber is pricier and interconnect involves a few more pieces and setup, cost for pre-terminated patch is coming way down, as are SFPs and switches.

The OP could probably get away with copper, sure, but burial-rated fiber patch isn't as outlandish as it used to be, and as long as he's digging anyways...
 
Last edited:

Daybreak

Regular Contributor
@Trip
True.
Everyone was way overthinking this situation. They need to step back and remember what the end result is. :)
Fiber patch works, yes.
If it was some 40 computers at location A, and 40 computers at B, and needed real network access, sure. Even a simple wireless bridge would work fine.
 

tekrich

Regular Contributor
Keep it simple.

A wireless link should be your last option.

Fiber is overkill here; 23 meter line. 30 meters, just to round it up, is not that long.

Bury or suspend a CAT6 cable across the buildings and call it a day. Reliable, simple, trouble free.
 

lloydo

New Around Here
Thanks all for your responses, I have taken on board the advice to bury a wired link!

In particular, this was an interesting post. I had not heard of these sorts of problems before!

if you don’t bridge between buildings with point to point wireless then use fiber to avoid ground loops burning out hardware due to the difference in voltage of the earth surface at each building.

Does each building have its own electric drop and service meter ? I would assume you are on a system similar to the UK ?
I don't know much about the electrics, but I'd assume they are separate, yes.
 

Trip

Very Senior Member
Fiber is still best-practice when running between buildings, but Cat6/6a will certainly work. I would use shielded cable and ground one end of the run, though, to isolate electrical current between buildings.
 

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