Ethernet-over-Power

Months ago, someone was chatting about some network upgrades they wanted to do for a local hackspace, and he mentioned “ethernet over power”. I chuckled and pointed out that he meant “power over ethernet”, to which he said that no, actually he had meant what he had said; there is such a thing as ethernet over power.

And it is really, really cool.

It took me a while to find the technology, so if you go looking for it, try the keyword “powerline”.

What Does It Do?

Let’s say you have your modem (the box you get from your ISP when you sign up for Internet service) in the downstairs lounge, but your main computer is over in your office three rooms away, and your home server is stuffed away in a closet upstairs. You may also have a Roku hooked up to your TV, and a laptop that moves around (as laptops do).

No problem; you have wifi and maybe you fiddle around with the broadcast channel settings so that you get low noise, and your little intranet chugs along nicely.

Until one day you notice that a 4gb download of the latest Slackware ISO is just a little slower than you feel it should be, and a 25gb download of the latest SteamOS game takes all night, and maybe you notice that Netflix feels laggy when you are fast-forwarding or first loading a show. Maybe you get complaints from your users that your home server doesn’t feel as snappy as the big professional Cloud services they are used to, and when you go into that one corner of the house with the laptop, it all but loses any usable signal.

What you really want to do is wire your house, but maybe you’re renting, or else you’re just not ready to go drilling holes in walls.

You could augment your wireless network with repeaters; that sometimes works. But some houses are just unfriendly to wifi, or maybe you find that even with wifi repeaters, the speed promised by your ISP (they’re lying anyway) are not the speeds you are getting.

With ethernet-over-power, you plug one unit into the AC power port near your modem and hardwire an ethernet cable from your modem (or switch, if you’re using an external switch or router) into the unit. You are now sending ethernet data packets on the copper cables of your home power grid. Plug another unit into the AC power port somewhere else in your house, and run a cable from that unit to whatever computer is nearby (your desktop, laptop, Roku, home server, whatever) and that device is now hardwired into your network.

Does it Work?

I was ready for this crazy idea to fail miserably. I figured that the data would surely get degraded running on the same lines as my electricity, so I expected it to technically work but to ultimately be no better than wifi repeaters.

But for Christmas, I was given a 500mbps starter kit; it came with two “powerline” units, one for the modem connection and one for a receiving device.

The first go did fail miserably, but not because of the technology. It turns out that the cheapest of powerline units do not have AC passthroughs, and the inbuilt surge-protection of most powerstrips interfere with the data. So the cheap ones are useless unless it can be plugged directly into the AC port on the wall. This was not possibly for me (not enough power points for all the devices plugged in).

So I returned it and upgraded to a model with AC passthrough. This enabled me to plug the powerline box into the wall, and then the powerstrip needed to power my computer into that. Very handy, but a little more expensive.

Aside from that, setup was plug-and-play. I plugged the powerline units into the wall, wired them to the modem and the computer, pressed the buttons on each to marry them together, and that was it. Job done.

I had intended to do some benchmarking to prove to myself that the network speed had indeed increased but there was no need; I switched my computer over to the wired connection, launched Firefox, and pages loaded instantly.

It was a night-and-day difference.

Your mileage may vary; I have a high tolerance for network performance, so modest improvements feel pretty major to me. If you’re trying to squeeze every last megabit per second out of your connection, powerline might not change your world (maybe look into fiber?), but if your problem boils down to poor wireless performance, then powerline may well solve all your problems.

Cost

The powerline unit I originally got was $80 NZD ($50 USD?) for two. The upgrade I ended up having to get due to my reliance on powerstrips was $110 NZD. Gigabit-capable units are available, but they are more expensive; I just got the 500mbps model, because my current home network is 100mbps.

If your aim is to hard wire an entire house, this could add up, although you might be able to use a mix of AC-passthrough units where you need powerstrips and the cheaper ones in places that you have plenty of AC power points.

But is it Secure?

I just got these two days ago, so extensive tests have not been performed. I plan on doing a scan of my network from my modem, but what I’d really like to do is to plug a third, rogue adapter into a power point and see what it picks up.

As far as I can tell, there is no user-facing way to set encryption keys, so I’m assuming the powerline units use some default set of keys, which presumably also means that if these keys were obtained from the manufacturer and published online, they could be used to decrypt the data.

I have very little knowledge of how this works; I’m guessing the ethernet packets get filtered out by fuses and doesn’t get sent out all over town, but who knows? I understand the principle, but the actual implementation is a mystery to me so far. More research is required.

Bottom Line

All in all, ethernet-over-power has drastically improved the network performance of my desktop computer in a way that I was unable to do with a wireless repeater. I recommend the technology, but cannot speak to the security implications until I do more research.