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Too bad this is 10Gbase-T, that energy-wasting hot-running garbage needs to die sooner rather than later. Good thing the ranges for 25Gbase-T are short enough to make it impractical for home use.

(Fibre is nowhere near as "sensitive" as some people believe.)



The problem with fibre isn't the sensitivity. It's that most endpoints have a 1Gbps copper port on them and then Cat6A ports can be used with the common devices but also allow you to add or relocate 10Gbps devices without rewiring the building again.


However — unlike copper twisted pair — the bandwidth current fiber media can carry is nearly limited by nothing but the optics at each end.


That doesn't solve the chicken and egg problem.

What probably would is something like having PCIe and USB to 1Gbps fiber adapters that cost $5.


You've been able to get Intel X520 NICs [0], with transceivers included for ~40USD on Newegg for a long time. This is a little more than double the price of Newegg's cheapest single-port 10/100/1000 copper card, but even the cheapest available such card is three times your "chicken and egg"-solving price point.

I suspect the combination of the absence of cheap-o all-in-one AP/router combo boxes with any SFP+ cages and fiber cabling's reputation of being extremely fragile have much more to do with its scarcity at the extremely low end of networking gear than anything else.

[0] This is a two-port SFP+ PCI Express card


You can get copper ones for $5.99 (quality may vary):

https://www.amazon.com/1000Mbps-Network-Performance-Gigabit-...

https://www.amazon.com/SALAN-Ethernet-Portable-Internet-Conv...

But it's not competing with those, it's competing with the copper port which is already built into most devices.

Another thing that would work is something like this (also $5.99), but with one of the ports as fibre:

https://www.amazon.com/Gigabit-Ethernet-Splitter-1000Mbps-In...

The point being you need some cheap way to plug in existing copper devices if you run fibre to the endpoints.

This plus $5 for a transceiver is pretty close at $15:

https://www.amazon.com/Gigabit-Ethernet-Converter-Auto-Negot...

But +$15 and an extra wall outlet per endpoint is still an inconvenience, and if a two-port device with its own power supply can be made for $15 then where is the PCIe/USB to fibre adapter for <$10?


> (quality may vary):

Yep. Good NICs last for approximately forever, life's way too short to deal with maybe-flaky NICs, and the price difference between the Amazon Special and something that's going to be reliable is -what- two big boxes of Cheerios? Two dozen eggs? Not. Worth it.

> But it's not competing with those, it's competing with the copper port which is already built into most devices.

Correct! That's part of why I was so very surprised to see you suggesting that extremely cheap PCI Express and USB adapters would "solve the chicken and egg problem".

> The point being you need some cheap way to plug in existing copper devices if you run fibre to the endpoints.

That's called a multi-port switch. Netgear sells five-port gigabit ones for like 20 USD. Switches that have two SFP+ cages and eight copper gigabit ports [0] are six times the price of a cheap-o Netgear switch, but are something that's going to last at least a decade. It's also pretty uncommon to find SOHO switches that have SFP+ cages and don't have at least one fixed copper port.

> This plus $5 for a transceiver is pretty close at $15:

If you're connecting a single device, why the hell would you use that when you could slap a copper SFP or SFP+ module in the switch's cage and run a cable? If you're connecting multiple devices, then either install multiple copper modules and run multiple cables, run multiple copper cables from fixed copper ports on the switch, or put a switch where the existing copper devices are.

[0] <https://mikrotik.com/product/css610_8g_2s_in>


> If you're connecting a single device, why the hell would you use that when you could slap a copper SFP or SFP+ module in the switch's cage and run a cable?

The problem to be solved is that you want to be able to put fibre inside the walls of the building instead of copper. Running a new cable to the switch closet is the thing to be prevented.

But if the wall jacks are fibre then you need some economical way of hooking them up to every printer and single-purpose device with a network port. If you have to buy another $100+ switch just to get from fibre to copper even when there is only one device near that jack, people aren't going to go for that.


> The problem to be solved is that you want to be able to put fibre inside the walls of the building instead of copper. Running a new cable to the switch closet is the thing to be prevented.

...why would you ever not run copper alongside fiber for new construction? If nothing else, PoE is extremely useful, and nothing says that you actually have to connect all of that copper cable to your switch... you can connect it as-needed. I also can't imagine that most refits only have room for exactly one cable in their conduit. [0]

I'd expect to hear the sort of plan you propose from a PHB or Highly Paid Consultant, not someone who actually has had to use that sort of configuration.

Regardless, the scenario you're now proposing is one where noone other than a PHB would use that Amazon Special that you linked for media conversion.

[0] If there's no conduit and cables are all flopping around in the wall, then there's even more room for cabling.


The original problem was that everyone runs copper instead of fibre because there are too many existing devices that only have copper. Running both everywhere would require you to buy and terminate twice as much cable as you expect to use, which leads people to running only copper again.

If you chose PCs to begin with that come with fibre ethernet or put quality cards in the ones that matter then you could make fibre the default instead of copper. Until you have a number of devices like printers or VoIP phones or Raspberry Pis that have no need for 10Gbps or even 1Gbps connectivity, they just need a way to be plugged in at all. If you need to add $100+ in conversion expense to each of those devices, you're back to using copper by default.


> Running both everywhere would require you to buy and terminate twice as much cable as you expect to use...

Ah. Let's play with that logic a bit:

"Running Ethernet cabling everywhere would require you to buy and terminate far more than twice as much cable as you expect to use. Just run power cables and wire up one extra outlet for a HomePlug in each room.".

Yeah, that checks out. "Powerline Ethernet" devices are actually pretty good these days, and are right around your magic price range... Amazon has them at ~13 USD per unit. [0] Why would anyone bother running a second cable to each room? Thirteen bucks per room has to be way less than the materials and labor cost for the cable run. Doing anything else is, like, really stupid. Don't you agree?

Anyway. You expect to use the cabling that you plan to install... plus some extra for screwups, man.

[0] <https://www.amazon.com/Linksys-PLEK500-Homeplug-AV2-Powerlin...>


Running a new cable is easy. You just use the old cable to pull the new cable. You can run composite cable if you desire copper, fiber and power.


> You can run composite cable if you desire copper, fiber and power.

Oooh. Cool.

By "power" do you mean 120/240VAC, or do you mean much lower voltage DC? I've found some Belden cabling that I think provides mains power and Ethernet, and I've found fiber cabling that I guess carries lower voltage DC, but am having a tough time finding a cable that combines fiber and copper data with mains power. Do you have an example of such a cable handy?

(Full disclosure: I'm refusing to spend more than like five minutes on the search... so I might have been able to dig up examples of such a cable.)


Which is why people run only copper because that costs less than running multiple types of cable everywhere when most drops only have one device, and then pull fibre through using the existing copper cable in the rare instances where they find a need for 40Gbps or more.

But then the copper gets used for 10Gbps connections instead of fibre because it's what's already in the building.


In practice though 10G via copper requires pretty perfect terminations. The slightest error leads to crosstalk issues.


Ymmv. I've got a mix of cheap premade patch cables and some I crimped from solid core, all cat5e, all holding 10gbe totally happily. I suspect that only works because they're a meter or two long but that reaches across the rack.


NICs have DSPs to cancel out crosstalk.


Good thing the ranges for 25Gbase-T are short enough to make it impractical for home use.

Anyone who talks about 25GBASE-T like it actually exists, doesn't know anything about what they're talking about.


Or is speaking in future terms.

40Gbase-T will never exist, sure. 25Gbase-T very likely will.


Is the energy consumption inherent to 10Gbase-T? Or is it that 1Gbit nics have been around forever and optimised ad infinitum?

To be fair, the power consumption is also my biggest gripe with my WiFi 6 AP, they run extremely hot.


It's inherently worse than anything fibre, or even DAC cables (which are kinda cheating.) It needs a shitton of analog "magic" to work with the bandwidth limitations of copper cabling.


Just wondering why you considered DAC cables cheating, is the analog magic mainly the impedance matching or I'm missing something?


DAC cables are cheating because due to the extremely short range limits (5m, 7m if you're very lucky) they can just put the 10Gbase-R/SFI signal straight on a pair of Copper at 10.3125 Gbaud.

10Gbase-T, to try to get to 100m, throws FEC on it and converts the signal to 4x PAM-16/THP at 800 Mbd, and then uses 4 copper pairs *bidirectionally*. That's the analog magic.


Okay. Sure. But why do we notice that on 10GbaseT and on 1? Is there some signal processing which is exponentially expensive at faster speeds? I’ve seen cards using 25W per port.


cf. https://news.ycombinator.com/item?id=47908287

Yes, that signal processing is massively more expensive. A 10Gbase-T PHY is a sophisticated DSP. Not sure if the power needs are exponential, given we only have a few data points, but it's in the ballpark.

(1000base-T PHYs are already DSPs, but nowhere near as sophisticated)


How easy can an ordinary home user install fiber in his home compared to a good old wire?


There’s nothing hard about it if you can run pre-terminated patches. Which you typically can since the connectors are so small.


So you're saying users could buy stuff like this? "25m (82ft) Fiber Patch Cable, 1 Fiber, SC APC Simplex to SC APC Simplex, Single Mode (OS2), Riser (OFNR), 2.0mm, Tight-Buffered, Yellow", https://www.fs.com/eu-en/products/282133.html?attribute=1031...

Heck, I don't even know what I should buy for 10G SFP+ ports and a distance of say 30 meters. Guess, I'm back to CAT6 :-)


> Guess, I'm back to CAT6 :-)

If you learned what you need for 10GbT you can learn what you need for 10GbLR. Which is:

LC connector, PC or UPC, duplex, OS1 or OS2, and SFP+ modules saying "LR".

Any of the following is wrong: SC, FC, LSH, E2000, ST, APC, simplex, OM[1-5], "SR" or "ER" SFPs.

And that's short enough.


LC connectors are smaller and what the actual SFP+ modules typically have. If you want to run a link with just one fiber, you need BiDi optics.

FS does custom multi-fiber cable assemblies too (beyond the duplex patches which is basically the standard), and they can also include pull eyes on them if that’d be helpful.

Single mode is a good choice, common wisdom used to be multimode for short runs but the single mode stuff is not much more expensive and the standard 10km optics will likely brute force the signal over any mistakes like cable kinks or dirt on the connectors.


Fiber is way easier to run than copper. If you already have copper just use that to run the fiber.


Nothing in my home has SFP ports other than my routers and my primary network switch (two, hooked up to the routers). All of my computers and USB adapters for laptops expect RJ45 at 10/100/1000/2500/5000/10000 Mbps. None of my runs are over 50 ft.

So IDGAF about how much "better" fiber is. It's unfathomably worse when you factor in the cost and work I'd need to do to convert everything and every new adapter I'd have to buy or build (can I get an $80 USB SFP adapter? Do I have a cable?). The extra marginal cost in electricity will take longer than the lifetime of my equipment to exceed the cost of redoing everything.




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