Extend Network to multiple Buildings

pc-tecky

Member
May 1, 2013
200
25
18
I'm curious to know what you would consider using to extend a network between buildings capable of supporting VoIP and less than 200 feet apart with parking lot traffic between them?

Wireless AC or some "armored" aerial guy wire suspended fiber?
 

zunder1990

Member
Nov 15, 2012
70
6
8
If you have clear of sight take a look at the following options

isostation-ac ~140 Mbps $150-200 for the pair

airfiber24 ~600-700Mbps full duplex $1400 pair

airfiber24-hd 1Gbps full duplex $3000 pair

If I remember right the airfiber have a min spacing or 100feet or 100meters.
 

zunder1990

Member
Nov 15, 2012
70
6
8
Most of the time running Ethernet between building can cause a lot of problems. This is because of difference in ground potential, it comes down to there can be small charge on the ground/neutral power lines for the building. This charge can be different between building will try to equalize between the two building. This equalization is not a problem in a normal home setting since the outbuilding has it power feed from the main building and there is a ground wire running between the buildings. However in a normal office setting building are on there own power connection and there are no ground wires running between the buildings and then enter your Ethernet cable. This cable will try to equalize the ground between the two building and kill the network interface that the cable is connected to.

TLDR:
Do NOT run Ethernet between buildings, If one of the wireless options does not work for you then run fiber. The materials cost between fiber and cat6 is almost the same.
 
  • Like
Reactions: Aluminum

rune-san

Member
Feb 7, 2014
78
15
8
It depends on your needs. In all honesty, choosing to run wireless vs. suspending fiber are simply two entirely different worlds of needs. If you need enough bandwidth, or enough guaranteed quality of service to consider suspending fiber, you wouldn't be evaluating a wireless solution.

If you have the money to run it, and can't trench it, suspending fiber is a good option. But that will require a solution for lightning protection, height codes, and all the usual regulatory stuff.
 

maze

Active Member
Apr 27, 2013
556
84
28
+1 on the not running ethernet cables. not sure what its called in english. But something around it being different electrical inlets can cause big problems.

I'd either run a fiber (pref in the ground, but alternatively between buildings in an outdoor armored cable). Alternatively a wireless p2p connection, ubiquiti makes some quite decent ones for a relatively affordable price - depending on how much throughput you want.
 

wifiholic

New Member
Mar 27, 2018
2
1
3
33
Definitely do not run copper between the buildings. Because of the ground potential differences that others have already discussed, any nearby lightning events are almost guaranteed to fry something, so ... just don't.

With that said, if fiber is out of the question, the Ubiquiti AirMax options (5ac Isostation or Nanostation or Nanobeam) are a great choice on the lower end in the 5 GHz spectrum, and are all good for a couple hundred megabits per second. The Ubiquiti 24 GHz AirFibers are wonderful radios, but probably overkill for what you've described (they're also $1400 or $3000 per end, respectively, so double that for the cost of a complete link).

If you're looking for something out of the possibly crowded 5 GHz spectrum yet more affordable and with higher bandwidth than can be gotten from 802.11ac-based gear, consider the [sure to be controversial, and not yet proven] Mikrotik RBwAPG-60ad kit at under US$200 (although I just installed one a couple weeks ago and it's been ok so far, knock on wood), or the [off to a rocky start but doing much better now] IgniteNet MetroLinq for around US$1000 for a pair. Both products operate in the 60 GHz band, so they're for shorter links and much less susceptible to interference. Either one will get you a gigabit per second in one direction and even - in ideal conditions - 1 gbps in both directions simultaneously.
 
  • Like
Reactions: Aluminum

pc-tecky

Member
May 1, 2013
200
25
18
Wow, I wasn't expecting all of that. But very insightful.

If the wireless solution supports VoIP phones and APs, then everything else simply and literally falls right into place. I just recall back when VoIP and WiFi were both emerging (roughly ~2007), that the two technologies just didn't work all that well, and especially together with VoIP over WiFi with their specific needs, with jitter and lost packets. If the wireless won't or can't work like this, then the last standing option would default to fiber, with a boat load of more option and related questions.

All the buildings are adjoining, well under 200 feet apart, and on the same block, so the power ideally should also be sourced from the same sub-station, and well grounded (electrically). The driveway/parking lot allows for 2 (doubt 3) utility/service or box vans (Sprinter 3500, F550/5500 Cab & Chassis, etc.) in series, or ~5 in parallel (guessing).

The main building (under 200 feet long), some claim the ~150 foot CAT5 LAN cable for the back computer, and a straight run, just barely makes connectivity, but it also runs along the central load I-beam in close proximity to the various high voltage power lines (for a welder +/- plasma cutter, etc.) and I imagine that the CAT5 LAN cable is not shielded either.

Using an existing conduit or burial of a new conduit would be nice, BUT it would definitely destroy the driveway/parking lot for a very long weekend (asphault or not, still rough) given all the unknowns. It would, however, offer the opportunity to centralize the air supply between the buildings with the option for parallel or fail-over redundant systems.

The Unknowns:
Is a 1/2" conduit big enough for pre-terminated fiber or is it a limiation? (potential cable sources from discount-low-voltage.com or fs.com)
- a video from discount-low-voltage states a minimum 1.0" conduit for their sleeved and pre-terminated fiber ready to pull solution
Are the locations or path of the ('ducted') conduits below ground known?
Does the existing conduit have sweeping bends or harsh/tight bends? how deep does it go or the over all conduit length?
Are the conduits simply for egress using direct bury cables?
or Are the conduits "ducted", that is open end to end with no obstructions, corrosion, or otherwise collapsed?
Do we know where all the utilities and services are located (water, sewer, gas, storm drains, etc.)?
 

wifiholic

New Member
Mar 27, 2018
2
1
3
33
Fiber would be great if you can do it, but based on my experience pulling pre-terminated fiber, I'd trust the recommendation for a 1" conduit.

For wireless bridging, on the other hand, as long as you're dealing with VoIP as in SIP, not AoIP protocols like Dante, Ravenna, or AES67, a wireless bridge will work just fine as long as there's enough bandwidth for everything that needs to go over it. Ubiquiti says that they support QoS, which is probably enough, but if your VoIP traffic is on a separate VLAN, an alternative option to be extra safe would be to set up two wireless bridges on separate wireless channels to provide transit for the voice VLAN separately from the other VLANs. (By the way, when configured correctly, all of these wireless bridges will function effectively at layer 2, passing VLAN tagged traffic intact.)
 

Aluminum

Active Member
Sep 7, 2012
431
45
28
All the buildings are adjoining, well under 200 feet apart, and on the same block, so the power ideally should also be sourced from the same sub-station, and well grounded (electrically).
No, do not think this way, it is not that simple. Different buildings will have different grounds, do not link them up over copper. Even a shed in your back yard off the same circuit breaker can be different enough to cause issues with sensitive equipment - seen it before. Ethernet interface circuits definitely fall under the sensitive equipment category; lighting, heaters or DC warts for remote devices do not.

Also "<200 feet" once you account for the actual cable path between 2 buildings is probably approaching copper ethernet limits anyways. Fiber is not much more expensive than copper at the same lengths (most of your actual cost will be conduit/digging/construction/whatever) and leaves tons of room for future growth, so if a dedicated wireless link is not enough then that is the only sane option for multiple buildings.
 

fractal

Active Member
Jun 7, 2016
312
69
28
29
Some people over think the "different grounds". Ground is ground. It is the stuff outside your building. How well your electrical ground is connected to earth is a subject for debate. Gigabit ethernet is differential. It doesn't care about ground / earth / anything. It is the difference between the two wires that matters. The standard requires equipment to be able to withstand a bunch of volts between the signal carrying wires and earth.

That said, I too dislike running ethernet between buildings. Good equipment will tolerate ground differences. But externally induced spikes are a different story. It is for that reason I recommend a non-conducting solution between buildings. Fiber is a great, low cost solution.

If you trench, don't cheap out on the conduit. I see people spend 10k to dig a hole and 500 for small conduit when proper size conduit would be 800. Go big. If you think you need 1 inch, buy 2 inch. The price difference is negligible compare to the cost of digging the hole.
 

Terry Kennedy

Well-Known Member
Jun 25, 2015
1,062
501
113
New York City
www.glaver.org
Some people over think the "different grounds". Ground is ground. It is the stuff outside your building. How well your electrical ground is connected to earth is a subject for debate. Gigabit ethernet is differential. It doesn't care about ground / earth / anything. It is the difference between the two wires that matters. The standard requires equipment to be able to withstand a bunch of volts between the signal carrying wires and earth.
"Ground is ground" can lead to problems. At the college I used to work at, they wanted to build a secondary TV studio in another building and link it via coax to the main studio / building a block away. This was in the 1980's, so it was coax, not fiber.

There was hum problem, so some genius decided to just run a hefty piece of 4/0 copper between the buildings. He hooked it up to a structural beam in one building, went to the other building, stripped the end and accidentally bumped the beam he wanted to attach it to. He got a large shower of sparks, the wire welded itself to the beam and proceeded to develop a nice orange glow (after the insulation melted and fell off). The 2 buildings were on different substations and had rather different ideas about "ground".

Utilities will often go to extreme lengths to get a good ground. While probably way off the far end of the bathtub curve, the Path 65 Celio Converter Station has "... grounding system at Celilo consists of 1,067 cast iron anodes buried in a two-foot trench of petroleum coke, which behaves as an electrode, arranged in a ring of 2.02 mi (3,250.87 m) circumference at Rice Flats"
 
  • Like
Reactions: Scott Laird

fractal

Active Member
Jun 7, 2016
312
69
28
29
Oh, I have horror stories too. But those are ancient ... like me.

For what you described to happen, they are lucky someone did not get electrocuted on a rainy day because "ground" at one of those buildings was substantially different than earth.

European standards have neutral tied to ground at the substation and run neutral to every location. It is not uncommon for neutral to be hundreds of volts above ground using their standards. But, since everything is differential, it just works. Ground is just ground and is locally sourced. It is a safety ground.

US standards have neutral tied to ground at the point of delivery. It saves a bunch of money by not having to run a neutral to location. And, if you have an electrical install to modern standards, you can run cat5 or coax longer than signal integrity allows with no risk of ground problems.

That said, not everyone has a modern electrical system. There are plenty of buildings that were build in the 60's and 70's (and earlier) where code said you could use your water pipe as your primary ground. That was great when everyone used copper pipes for water. Things got dicey when the copper started to leak and was replaced with plastic ;) Your neutral and hence ground floats based on the difference between your two live legs and your neighbor's ability to sink it. Get an old neighborhood where nobody maintained their electrical panel and replaced their copper water lines with plastic and the one guy with a proper ground rod can see his glow <smirk>. Hence the horror stories.

My house is now "to code as of 2017" since they did a solar install. I have two ground rods 6 ft apart next to the main panel and another pair bonding the panel frames. Oh, and both hot and cold water are bonded to the ground system, as is the gas line, with an unbroken conductor. Oh, and those grounds are armored unlike my first house I upgraded in the 80's. So, yes, at least in my house, ground is ground.

So, yes, there are horror stories of improper grounds. And yes, they are worth listening to. But take them with appropriate skepticism. They are easily mitigated by driving ground rods willy nilly. They are harder to completely eliminate, hence my guidance to run a non-conductor.