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fleventynine

I don't think permanently wiring high-speed twisted-pair makes much economic sense:

CAT8: $0.55 / foot

Max speed; 40 Gbit

Max length: 30m

(https://www.monoprice.com/product?p_id=42957):

---

2 strand OS2 single-mode fiber: $0.09 / foot

Max speed: 800 Gbit (today; theoretical max speed is much higher)

Max length: >10km

(https://www.cablewholesale.com/products/bulk-cable/fiber-opt...):

OS2 has been around for decades, and will be more than good enough for the next several decades.

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First, fiber rules out PoE, which is one of the major advantages to a wired network to begin with. Devices like APs, cameras, and phones will need local power, which is going to add a lot of expense and/or installation complexity. In most installations today power delivery is one of the main purposes of network cabling.

You'll also need either fiber interfaces or media converters, which besides cost is an installation complexity. It'll add another thing you need power for and more equipment to conceal (or leave visible...) at each AP. Even assuming all of your devices are all full-on desktop computers I think the higher price of fiber NICs will eat much of your savings.

PoE is awesome, I've been using it for years but it still feels like the future when I plug in a device and it boots up with power+data.

I just ran a couple runs to an in-wall AP + 2 1gbe port(w/ one PoE) and it's so awesome to have that all done with one cable.

Btw, instead of PoE, you can also look into ethernet-over-powerlines. That way you can re-use the power cables you already have in your home.

It can be unreliable (depending on the socket used) and causes radio interference though.

That tends to be much slower and have issues.

While that’s an interesting idea, is there really any point in using anything beyond Cat 6 given the connectivity found on most devices today and for the foreseeable future? Terabit-supporting fiber is cool, but ultimately not that useful when all my devices only have gigabit Ethernet, or 10gig Ethernet at best. I can’t see SFPs showing up on mainstream consumer devices anytime soon, which renders the fiber dream impractical for a home environment.

I am not familiar with the tools and cost associated with terminating fiber, yet I can easily do that for copper cable.

Also- I am a big fan of PoE. My ceiling mounted aps depend on that for power. With fiber now I need to also run power to access points, whereas I only have one cat6 cable for power plus data.

Seems fine? Our house has Cat5e going back to ~2008 (before we owned the house). It supports my 2.5Gbps PoE AP uplinks.

We're about to remodel and this has me thinking I should go to Cat8.2. Maybe a thousand bucks in cable? If that? I'll also add fiber for the furthest reach of the house for "future-proofing" but fiber is the tech that keeps being promised Real Soon Like Now but nobody's using it for their devices.

If you have drops where you want them, test what you've got installed. Cabling that only hits the minimums of Cat5e doesn't meet the specs for 10GbaseT, but the specs for 10G are for cabling in a dense conduit with a total run of 100m. In a residential setting, you likely don't have dense conduit or there's only a small section with dense cabling, where it leaves the patch panel. Additionally, cables are often exceed the spec they claim on their jacket, especially when there were not higher specs defined when made. My house was cabled with cat5e in 2003 or so, and I run 10g along one segment joining two buildings without significant error counts. My systems lack the tuning to really use that bandwidth, and I don't have a real usecase, but I wanted to see if it works, and it does. I've also run gigE over a segment with a mix of cat5e and cat3 at my previous residence, because pulling a new cable would have been onerous; and 100M would have been acceptable if gigE didn't work.

I'm not sure that cat5e will work beyond 10G, but 10G seems likely to be good enough for a long time. As of right now, used 10g fiber equipment is significantly less expensive than used 10GbaseT equipment, and there's power/heat savings too, 40GbaseT is going to run really hot.

Good point -- I actually have tested and can only manage a 2.5Gbps link between the 2 devices and two drops I have to test with. I also agree 10Gbps is likely to be good enough for quite some time.

Running fiber across the house to my office at the far corner gives me the option of future-proofing a potentially higher speed link then offloading to usable copper closer to the point of usage.

In that case, definitely may as well recable during a remodel. Good luck with your project!

Do you know if cat 8.2 is backwards compatible with cat 5/cat 6. In particular, can I use cat 8.2 with older devices (albeit at lower speeds)?

Wikipedia says Cat 8.2 comes with different jacks, potentially. If you have enough pairs (2 for 10/100, 4 for 1G), and the connector is rj45 or compatible, higher spec wiring won't hurt you.

Depending on details that I don't know, you may not be able to use a cat5 patch panel or cat5 wall jacks with cat8.2 cable, if the wire sizes changed or the insulation won't be cut properly, and using underspeced terminations may mean your install doesn't test as cat8, but you can reterminate later if it matters.

Now let's see the transceiver and switch cost.

FS.com has transceivers at $8, and 5-port SFP+ Mikrotik is about $160.

They have transceivers for $8 sure, but are they 1/10Gbit transceivers, or are they 1/2.5/5/10 transceivers? Will they work with your switch? How long will they work for? (SFPs get crazy hot.)

Mikrotik makes an SFP module that's super reliable and supports 1/2.5/5/10. It's $53/unit.

Why would you want to run 2.5G or 5G over fiber? 10G fiber transceivers are dirt cheap and barely use any power. It's the 10G copper transceivers that have thermal/power issues...

I had 10G fiber transceivers crap out on me, for what it's worth. The Mikrotik SFPs are quite good though.

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