I'm seeing these powerline network adapters, and some at reasonable prices. Are they any use? I'm not inclined to get power surges or lightning strikes. I gather the better ones use two wires for the network link, and these are the ones to go for. https://www.zyxel.com/products_servi...er-PLA5405-v2/

Presuming there's no switch is it limited to one network channel, or can you get clever? Are the things hazardous security wise?

Yes, but it depends on your situation. I used them way in their infancy and while it worked ok it was very slow due to the technology. The cheap ones are probably 100MB so it should give you the same speed as if you were using regular ethernet 100baseT.

Depending on model they are typically a matched pair. Some of the more expensive models have multiple ethernet ports so at the remote end you may not need an additional switch. Supposedly the max distance is 100M so that should not be a problem. I am not all that familiar with your wiring but typically they should be on the same circuit/phase/transformer wiring. With 230 I do not see that being a problem.

They have worked well in my house for maybe a decade. Slowly bought faster models.
I don't use the encryption as I'd only one on transformer. Look at your electric panel and nearest transformer to decide.

They don't like being too far in circuits or subpanels.

@jefro
I have questions. Power companies in the US now use smart grid, smart electric meters. Your meter can be read remotely from the power company. They are using IP over power lines. And.., standard power from the power company is 138,500V. That can be split with a transformer with a center tap to get 2 legs of 69,250V, and that could be split again to 34,625V, and of course that is run to your house where a step down transformer gives you 170Vpp or 120vRMS from the end of the transformer to the center tap...blah blah blah.

My point it, the digital signal that the power company is communicating to your meter with, is able to cross multiple transformers. If they can read your meter, then they have access to anything that you plug into your LAN over powerlines in your home. Unless you have some kind of firewall to keep them out. Is that right or wrong?

How do you address that? Or what is stopping you from putting up that LAN traffic back up to the power lines through the transformer? Or do I have it all wrong?

Doesn't seem to have any effect. I have a "smart" meter on a smart grid where many of their devices upstream report every so often. My smart meter reading is usually 8 hours behind. I've read that the powerline won't go past a transformer due to frequencies used. I'd assume my smart meter does go over power line and not LTE like some models. I don't see any of the power company traffic. I did study that api while looking at using an open sourced power reporting program. The communication protocol is different.

If one wants then they can use the encryption feature. Pretty sure the encryption would be mandatory for apartments/dorms where many units could be on same transformer.

I have used a pair, they work OK, but I found my neighbours TV on mine, so I went over to wifi, even though not a secure system, but at least they'd need to find my password!

Thanks for the replies and questions, guys. It seems they work.

It seems the one I looked at (Zyxel pla5405-v2) worked between 2 & 86 Mhz. A bit slow for modulation, but they're probably selecting a channel for themselves somehow. It seems the ones that use both power lines are better. They're cheap here in places.
And that one offers 1300Mbps!

There's an even cheaper one with 3 outlets.

My wife has TP-Link ones that she's been very happy with. She has one that's a "normal" ethernet presentation, and the other that she uses at the remote end has ethernet and acts as a WiFi Access Point.

Apparently very reliable unless the cleaner unplugs them to plug in the hoover.

(Oh, and this is in a semi-detached in Dublin.)

In Dublin? It's a small world.

Just thinking about the 2-86 Mhz they use: They can use that as a carrier and amplitude modulate it with the 1Gbps signal. It's slightly trickier than your average A.M. radio, but doable.