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Comment by jrm4 | Hacker News Reader

I confess, I've read this twice and I don't really get what's going on here; and I have both MoCA and Powerline going on in my house as well, so I'm like -- why not one of those?

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Fiber is much nicer. You can get as much bandwidth as you'd ever want.

10G is trivially doable on cheap hardware. You can also go 100G, 200G or 400G over the exact same cable, it just costs a lot more on the endpoints.

If you run anything modern you probably can benefit from 10G at least. A NVME does 8 GB/s easily, it's a real pity to limit speeds to 1 gigabit. And Ethernet past 1 Gbps quickly gets pretty terrible to deal with, so might as well go with fiber then.

10G on twisted pair isn't too bad either. Used enterprise NICs are cheap on eBay. New low cost cards are available, too (still costs more than used gear, but if you want lower power or multigig, it's worth a look). Switches aren't so cheap, but IMHO, 10g-baseT is comparable to sfp+ and a transceiver on each end.

Obviously, if something is wrong with your existing cabling, 10g-base-t is probably not going to work either. 10G is probably the limit for twisted pair, but I think it'll hold up as a reasonable speed for a long time.

10G on twisted pair is terrible, it's power hungry and the SFP modules have a tendency to overheat. You need decent ventilation and not have 10G twisted pair connectors next to each other. Also only goes to 30M or so.

IMO, if you want 10G just go with fiber, it's less of a pain and more reliable. With twisted pair you may find out that the module overheats at times and the link drops out.

I don't use sfp+ modules for twisted pair... It didn't cost anymore to get nics and switches with the ports I need vs sfp+ and transceivers; although there's a lot fewer switches to choose from. 30 meters feels like a lot for most homes. 10g-base-T spec calls for 100m on cat6a and 55m on cat6. Running on cat5(e) isn't to spec, but largely works in a home environment where you tend not to have to deal with a lot of crosstalk from dense conduit.

And the benefit is I didn't have to run new cable. Lots of homes have some twisted pair in the wall, very few have fiber in the wall. Homes from the late 90s on probably have cat5 for phone lines.

Sure, 10GBASE-T works. It's just not very good overall and you should plan to put your 10G on fiber any time you can. It's not particularly expensive or complicated. If you can't, then sure, use -T.

Until everything moves to SFP it's gonna be hard to make that transition for anything other than core runs. Especially if you need PoE - I've doubled my cable runs and lost a ton of flexibility.

I had to ditch my powerline network after an electrical upgrade to arcfault circuit breakers (which my city's code requires - there are AFCI breakers that work with powerline networking but I'd have needed to replace my entire electrical panel). I suspect that's going to be very common in future as AFCI becomes require more.

> […] (which my city's code requires - there are AFCI breakers that work with powerline networking but I'd have needed to replace my entire electrical panel).

The (US) electrical code requires AFCI (and GFCI) in general, and not just your city. The Electrician U channel from a few years ago, "Where and Why Do We Need AFCI Protection?":

* https://www.youtube.com/watch?v=jMjBGzyoWUY

Also "Where Should We Be Using Dual Function [AFCI and GFCI] Breakers?":

* https://www.youtube.com/watch?v=eVyLSkEN908

Powerline struggles to reach gigabit and has all sorts of interference issues, and MoCA is expensive and also not full duplex. Bandwidth goes down as you attach it to more nodes.

It probably depends on your house. I struggled in getting sustained 50 Mbps with three powerline adapters and some 5-10 metres between them.

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