"powerline adaptors" [0]
Basically, buy these adaptors and for ~$100, you can have create a "wired" LAN connection using power outlets in a home.
[0] https://www.techradar.com/news/the-best-powerline-adaptors
It took forever to figure out what was causing this, and I eventually figured it out by doing a (very slow) IP scan of every device on the network I was connecting to and finding a machine named with their first and last name. Unplugged the thing, and the problem went away forever.
If it hadn't happened to me, it's something I would have thought impossible!
(edited a small typo)
I think the newer ones all have some sort of encryption/pairing system which at least helps you ignore your neighbors transmissions.
X10 users have used them for years - you can find them with vendors that specialize in dealing with the X10 community or home automation; although with the wireless mesh networks like Zwave or Zigbee a lot of the powerline stuff has (thankfully) fallen by the wayside.
Another way to get wired internet without possibly running new cable is with MOCA - ethernet over coax. You can find cheap DirecTV branded MOCA adapters all over the place. Most are 100Mbps but if you watch the newer ones are gigabit capable.
That being said, I've worked with 10base5. Drilling for a vampire tap in an open elevator shaft is its own form of exciting.
I'm using a pair of TPLinks to feed a wifi router on the opposite side of my house. The outlets are definitely on opposite phases, but the powerline adapters still work reasonably well. (~80Mbps). Now I'm realizing I should probably swap a couple of circuits and improve that connection.
But brute force works too :)
Speeds won't be great for that sort of ethernet-over-phone wire, especially because most landlines used awful, cheeap wires, but in some cases it is faster than powerline adaptors.
Unfortunately all the companies that produce such equipment for "phone line adaptors" sell only to the phone companies and never directly to consumers.
So many houses today have vestigial phone wires that no one is using for anything.
There's a lot of things that made Cat 5 cheap for running phone lines in houses and most of them make Cat 5 useless for Ethernet, unfortunately.
If you've got an old house with old telephone wiring, it's probably wired as a bus, if you want to re-use that for ethernet, you'll want to split it up so each phone jack gets wired as two ethernet jacks; one in each direction. If you're using ethernet in the room, you'll need a (small) switch, and you'll want to be careful to buy 10/100 switches if you've only got two pair as Ethernet autonegotiation can easily do the wrong thing and you don't want to pay for managed switches in each room. If there's no ethernet use in a room, still wire it up for two ports, but put a small patch cable between the two.
If you've got star topology phone wiring, there's a better chance of cat5 cabling and 4-pair and you can run gigE. GigE will sometimes run on cat3 for small distances too though. The only question is if the central location where the star wires meet is convenient for a switch. In a pinch, you can use a PoE powered switch and power it from one of the other ends of the star.
Of course, some houses are a mix of star and bus or generally some form of tree. Anywhere that there's a branch, you want to put one ethernet port for each direction. And hopefully all the branches are accessible.
There's really no need for DSL equipment in your own home, unless you've only got one pair wiring.
Well, 100BASE-TX will also run on single pair in half-duplex mode.
Alternatively you can also use powerline adapters over any cabling (twisted pair/coax/whatever). Just instead of connecting adapter prongs to power socket, connect to your cable and feed there enough power to supply the adapters. Around 50V DC (as commonly used by PoE supplies) will probably be enough.
I mean, kind of, but I don't know how you get network cards to run on a single pair? I'm actually interested, because if it works for 100BaseTx, it probably also works for 10BaseT, and I've got 10BaseT half duplex device I'd like to network, but only one pair available (there's a 3-pair cable run, but two are used for voice communication). I've tried a commercial product (ETSLAN Monoline Balun), but while I can get it to work a bit when testing on parts of the line, it doesn't work across the whole line; if I can just wire something more simple, that'd be worth a try too.
I would think the NICs would sense their own transmissions and declare a local collision?
True,especially when a microwave, washing machine or other motor starts sending noise down the power line...
I used it in home automation (Thank you Home Assistant) for mostly sensors, and less important actuators, where I had power, but could not get Ethernet, or WiFi.
Anything else, very unstable and too much latency.
I guess this also means inside your neighbor's home, if you live in an apartment building, right? That's why those devices typically use AES for encrypting the signal between the paired ones.
My apartment has some places that have coax runs but not ethernet runs.
Their performance depends on the electrical wiring in your house.
Ironically for me I’ve only managed to make them work on older electrical installations, and even then it was at best 802.11n speeds.
In my current house (newly built 2018), I can’t even get them to handshake. I suspect it’s due to improved electrical standards and better isolation between different circuits internally in the house, but I honestly don’t know.