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Comment by chrisBob | Hacker News Reader

I am about to put in a garage 300' from my house. I will already have a trench for power and water. What kind of network cable can/should I drop in the same trench?

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300 feet is at or beyond the edge of copper CAT cables, I'd run multimode fiber of the appropriate type (run a few to be safe?) - fiber doesn't care about power interference.

NOTE: See comments - I ran multimode because that's what the connectors in the off-lease hardware I had came with. Seems single mode is better in general.

https://www.lanshack.com or similar should have something in the $400 range.

You could be super cool and run conduit, but that itself has a cost (spooled conduit is what I'd do, but costly)

Multi-mode standards change too frequently, and it's not really much cheaper. Prefer single-mode.

+1 for lanshack, I've used them for pre-terminated cables for years!

I would go single mode — it’s cheaper, the optics are about the same price, and it’s more future proof.

Get a nice OFN/OFNR/OFNP cable and you don’t need to worry about grounding. And you can legally the same cable indoors too.

300 ft. is long enough that fiber will be the better choice if only to reduce signal loss. CAT6 has a maximum length of 328 ft., so while it would work, you're going to have a faster, more reliable connection all around with fiber.

If your garage is going to house cars or tools and it's questionable whether you need to run a network cable to it anyway, go for wired cable so you don't need a $500 fiber splicer. 300' is the maximum you can do, but the spec has some wiggle room.

If your garage is actually going to be a home office, you're a networking enthusiast and you feel running fiber would be a fun learning experience, and you've got a buddy who can lend you a fiber splicer (or giant holes you can fit a pre-terminated cable through) - then go ahead and run fiber if you like.

I barely use the network link I ran to my garage, and I literally have a CNC machine in there. Turns out sneakernet works fine when you've got to go set up the workpiece anyway, and I ain't buying a car that needs a wifi connection. A gold-plated setup would have been a waste of money.

I strongly recommend against this unless you have bonded earth connections between the buildings. During a storm the ground potential between the locations is likely to exceed the 1500V rating of the magnetics in your switches, and your equipment will be destroyed. Fiber is the only safe option at this distance.

In my country lightning strikes are rare, the equipment on each end of the link costs substantially less than a fiber splicing machine, and we get bonded earth connections as a matter of course.

I agree it's worth keeping an eye on your earthing, of course - if you get a noticeable difference in ground potential and you plan to plug in an EV charger outside in the rain, you might need some extra grounding. Unless your garage, your EV and yourself are all on an insulated concrete slab.

Voltage differentials in the earth that exceed 1500V will occur even without a lightning strike, and the greatest danger is when the ground is dry. Even something as simple as a strong wind blowing on a tree can charge things up significantly...

How interesting! How do old-fashioned wired telephones and cable TV deal with this problem?

The cable TV shield is grounded where it enters the house. The POTS lines aren't grounded (they're differential, like 1000base-T), but the telephone company installs some sort of protection device in the exterior box that allows sparks to jump across to the local ground if the voltage differential gets too high.

It’s so frustrating the amount of over generalization, anecdata that’s actually dangerous, and/or outright misinformation in this thread. Thank you for being one of the folks with spot on accurate info!

The garage will have a home office and TV area, so I need some kind of network connection. I was planning to use a wireless bridge, but it seems like it might be worth adding a run of fiber.

You don't need a fiber splicer for this. You can order a pre-terminated fiber cable online.

On fs.com you can order fiber in custom lengths. An armored pre-terminated 350ft OS2 duplex cable costs $128: https://www.fs.com/products/20720.html Non-armored would be as cheap as $40: https://www.fs.com/products/50147.html?attribute=58053&id=17...

If you don't have a conduit, you can buy direct-burial cable. Two strands at 350 feet would be $590: https://www.lanshack.com/2-Strand-CustomLine-Corning-ALTOS-O... 6 strands at 350 feet would be $687: https://www.lanshack.com/6-Strand-CustomLine-Corning-ALTOS-O...

If you have some extra length, just coil it somewhere in the wall and don't bother splicing or re-terminating it. You can also use keystone jacks or couplers at both ends too so you have flexibility later without re-running it through the conduit.

Make it easy to change your mind later, run some PVC conduit and make sure you include a pull tape for your networking stuff. A pre terminated fiber cable and some fiber to ethernet media converters should do the trick for isolation.

If you've got power already, why not consider a high bandwidth, wireless point-to-point bridge?

Just need two dishes pointed at each other. That hard line is nice until it fails, which it will eventually.

I have been leaning towards a wireless bridge. There are not a lot of houses around, so the environment shouldn't be too noisy. My only concern is that I don't want to mount something external on that side of my house.

A good brand link with directional antennas will punch through quite a bit. I just mounted the wireless units inside at one end for my sister (although I did choose a mounting location that had thin wall).

Fiber is both cheaper, more reliable, and faster.

If you ever want to send >1 Gigabit over that cable, use fibre. 10 GbE is pretty much the limit of copper cables at that length and create tons of heat (in the switch if RJ45 port, or worse on the SFP+ module). Also fibre has no fire safety considerations and no problem being right next to a power line carrying high-current AC. Also fibre does not corrode. As a bonus, it costs pretty much the same (but switches/sfp+ transciever are more expensive).

Put in conduit and you can decide later, replace eventually, or change your mind.

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