Ethernet over power devices. - Page 1
Forum section: electronics / general

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 11:13:24 am
content: Ethernet over power devices.I'm interested. Do they work? How do they work? Do you have any experiences with using them?Need to connect network between to freestanding dwellings 70 meters apart, same power circuit. Wifi wont cut it (I believe) and there is concrete in the way that I'd prefer not to dig up.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: May 25, 2012, 11:43:50 am
content: Dont worry about the Ethernet over Power devices. Not that I know anything about them.Use a wireless bridge based on a couple of Wireless Routers flashed with open source firmware and maybe slightly higher gain antennas mounted properly outside each building.The longest range I got out of such a system was 3km for compressed Video. Wireless G. ( With masthead antennas).RFshop.com.au has the stuff you need and may give advice.Look up DDWrt or OpenWrt .Who says Linux has trouble with Wireless?

author: BravoV
author_rank: Super Contributor
timestamp: May 25, 2012, 11:52:28 am
content: Use it to wire my garage which is separated from the main house building, its much-much better than wifi in term of latency and much less interference, especially you live in neighborhood with busy wifi traffics.Its very simple to use, it has two units, and just plug both at two power outlets that you're going to connect, and each unit has an ethernet port, wire it with ethernet cable and connect to your computer/router or wifi access point, thats it.Totally foolproof I'd say and quite secure too. Its just you have to make sure both power lines must in the same phase.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 11:55:11 am
content: Thanks for the reply. Yeah a directional antenna solution and a couple of hacked routers is the way isn't it?Quite familier with DDWrt, I own a Linksys 54wrt. Years ago, when I had time to do so, I printed out and read the whole src of one of the router firmwares at bedtime. Some folks don't understand why I cannot stand fiction of any sort.But that 'book' was a blardy good read.QuoteYou are preaching to the converted there, my friend.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 11:57:27 am
content: Quote from: BravoV on May 25, 2012, 11:52:28 amYeah, the out in the air transmission worries me a bit, but I can lock it down. But you never know do you - not that I've got any thing to hide.What throughput can you get?

author: BravoV
author_rank: Super Contributor
timestamp: May 25, 2012, 12:23:32 pm
content: Quote from: Ed.Kloonk on May 25, 2012, 11:57:27 amMy garage has two wifi cameras and one ethernet port with one desktop attached on it. I used to use wifi link with a repeater at the garage, its just the wifi's channels here are so crowded that sometimes made the video feeds stuttered, that pissed me off and made the decision to migrate the main network link to this powerline ethernet + an ethernet router with built in 4 port switch in the garage, and this solved all the problems perfectly.If my memory serves me right, last time I measured was approximately 30 to 40 Mbps, with two cameras constantly streaming to the main building, I think I got this number when I was trying to copy some files across this link and did some ballpark calculation, pretty good I'd say.Btw I'm using older generation which is maxed out theoretically at 85 Mbps, while newer generation capable of delivering 200 Mbps at 300 meters.About the power cable distance, my power cable length between this two devices is probably approx. 70-80 meters, not very sure though, but I'm quite confident yours should not be a problem.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 12:28:24 pm
content: Thanks.Tell us this. You mention generation of devices. Can you mix and match brands? Or do you think I should just get a "matched pair" so to speak.

author: buxtronix
author_rank: Contributor
timestamp: May 25, 2012, 12:56:32 pm
content: Quote from: Ed.Kloonk on May 25, 2012, 12:28:24 pmGet ones that speak the "Homeplug AV" standard. They are all interoperable with each other (much like analog modems all talk to each other).

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 01:18:01 pm
content: Quote from: buxtronix on May 25, 2012, 12:56:32 pmThanks. That's good to know. BTW, nice avatar. Hope that didn't hurt making that.

author: IanJ
author_rank: Unknown
timestamp: May 25, 2012, 01:48:24 pm
content: Hi,I have an outside workshop and wanted Lan/Internet/Webcam etc. there.So i've used homeplugs ranging from 85Mbps to 1Gbps over the past few years................and I've also used WDS, i.e. a wireless repeater setup...............and I've also run a Cat6e the distance.The most reliable connection i've had is with WDS.....everything else just too intermittent.Most good routers will support WDS (repeater mode). I have a Billion 7800n in the house offering up wifi there, and a Draytek 2820n in the outside workshop as the wifi repeater.......and with WPA2-PSK throughout. You don't need hacked routers to get a wireless repeater setup working.Fact is I'm out in the workshop typing this......:-)Ian.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 02:12:56 pm
content: Yeah, I hear ya. But trying to avoid the whole over the air thing in case the man comes and gets me.

author: Monkeh
author_rank: Super Contributor
timestamp: May 25, 2012, 02:16:29 pm
content: Quote from: IanJ on May 25, 2012, 01:48:24 pmIf WDS is more reliable than a fibre or copper connection (ps. no such thing as cat6e), then you're doing it wrong. Very, very wrong.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 02:20:36 pm
content: Quote from: Monkeh on May 25, 2012, 02:16:29 pmI'd say he meant cat 5e. But yeah, true dat.

author: BravoV
author_rank: Super Contributor
timestamp: May 25, 2012, 02:34:46 pm
content: Quote from: Ed.Kloonk on May 25, 2012, 02:12:56 pmSince your main concern is clear, I think currently there are no better and cheaper solution than powerlan ethernet.Regarding wifi, leave alone those crowded channels, even its secured and the secured link is not broken, when a script kiddies is heavily poking your system, this rogue activity alone will affect the overall throughput.While on the the security, imo its pretty good mechanism that they need to be paired at both connecting units on their mac addresses together with an AES encryption. Unless you're in those al-qaeda thingy or planning to assassin one of the head of govt.Quote from: Monkeh on May 25, 2012, 02:16:29 pm+1There is no way with current standard that wireless performance can beat wire connection provided within reasonable distance.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: May 25, 2012, 02:42:45 pm
content: I thought that with wifi there only really about three channels since the cross talk is ridiculous.

author: IanJ
author_rank: Unknown
timestamp: May 25, 2012, 03:10:01 pm
content: Quote from: Monkeh on May 25, 2012, 02:16:29 pmYawn!.....hate it when folks jump to conclusions..............1. You try talking to Draytek about their firmware issues and WHY long cable runs can be problematic.2. Try googling Cat6e.......I think you'll be surprised. I've got a 300mtr box sitting here.3. I never tried fibre.Ed.Kloonk,Truly hope you get a reliable connection with homeplugs if you try them. I had issues with dropouts due to heavy AC switching inducing noise/harmonics on the AC which didn't kill the homeplug but caused it to drop out intermittently. It does restart after a few seconds though.Ian.

author: Monkeh
author_rank: Super Contributor
timestamp: May 25, 2012, 03:17:48 pm
content: Quote from: IanJ on May 25, 2012, 03:10:01 pmThen get decent hardware.QuoteThere is no such standard as cat6e. cat6, yes. cat6a, yes. cat6e, no.

author: ToBeFrank
author_rank: Regular Contributor
timestamp: May 25, 2012, 03:48:19 pm
content: I use the the 200Mbps version to connect my AV equipment (TV, Bluray, xbox, wdtv) in the living room to the rest of my network. The powerline stuff is essentially bridging a switch in the living room to the main switch on the other side of the house. I have had zero problems. HD Netflix streaming works great. Streaming/copying files from/to the wdtv and my laptop is no problem. I did a throughput test when I first installed it over a year ago. I can't remember exactly what it got, but I think it was in the 80Mbps range. I know it is faster and lower latency than the 802.11n bridge I tried first. Of course the 802.11n bridge was competing with all the other wireless devices in my house so it's not really a fair comparison.

author: T4P
author_rank: Super Contributor
timestamp: May 25, 2012, 04:13:56 pm
content: Quote from: Monkeh on May 25, 2012, 03:17:48 pmAre you outdated or what ? Cat 6 enhanced is a 10Gbit capable cable at 500MHzhttp://www.binbert.com/blog/2010/05/differences-between-cat5-cat5e-cat6-and-cat6e-cables/Quote from: ToBeFrank on May 25, 2012, 03:48:19 pmNot the device you want if you live in a flat in a building ... somebody might not be exactly happy because my modem wasn't happy that somebody else's powerline wasn't filtered properly and was on the power supply AND the DOCSIS F-connector on the modem itself ...Now we know somebody bought a wing-wang-pong clone

author: Monkeh
author_rank: Super Contributor
timestamp: May 25, 2012, 04:19:45 pm
content: Quote from: DaveXRQ on May 25, 2012, 04:13:56 pm... Does not exist. It's cat6a, not cat6e. Go read TIA/EIA-568 some time.

author: T4P
author_rank: Super Contributor
timestamp: May 25, 2012, 04:36:10 pm
content: Quote from: Monkeh on May 25, 2012, 04:19:45 pmOkay. I can't find anything but i saw Cat 6a on wiki.

author: Monkeh
author_rank: Super Contributor
timestamp: May 25, 2012, 04:36:50 pm
content: Quote from: DaveXRQ on May 25, 2012, 04:36:10 pmBecause it came with some crap supplied by the lowest bidder from China, not a real, approved cable?

author: BravoV
author_rank: Super Contributor
timestamp: May 25, 2012, 07:53:16 pm
content: Quote from: IanJ on May 25, 2012, 03:10:01 pmEthernet technology is already matured for a very2 long time and will work as expected if the hardware/design/component are implemented properly, there is no need for "fix in firmware" for this matured standard, unless its not properly done, cheap parts/components maybe ?That Draytek brand stuff is yet another one hung low brand, get better and reputable network gear, you will surprise how good is the plain old ethernet compared to wifi.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: May 25, 2012, 11:24:42 pm
content: Sounds like an Ethernet over power might be a good excuse for a teardown, and or tutorial.What I can't under stand is how they claim/get similar (very roughly similar) specs to ethernet without the dedicated wiring.I am just wondering, what would work best in a block of flats? Everyone on Wireless N or Everyone on Ethernet over power.As far as which is the better solution, it is obviously horses for courses.Surely the quality of the network is heavily dependent on the house wiring for distance, other transmission line effects what other equipment is plugged in and possibly other equipment plugged into your neighbours house.In the same way as Wireless is heavily dependent on the antennae, fresnel zones, reflections, diversity, length of run and what other range and other devices sharing the same frequency.

author: Monkeh
author_rank: Super Contributor
timestamp: May 25, 2012, 11:26:10 pm
content: Quote from: HackedFridgeMagnet on May 25, 2012, 11:24:42 pmThe latter. You can filter it out at the distribution point so there's no interference.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: May 25, 2012, 11:47:16 pm
content: So do you just put on a choke around the cable?What if you cant get access to the cable coming to your distribution board?

author: ToBeFrank
author_rank: Regular Contributor
timestamp: May 26, 2012, 12:03:15 am
content: I was under the impression that HomePlug AV was only for in-home.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 26, 2012, 02:56:27 am
content: Quote from: HackedFridgeMagnet on May 25, 2012, 11:24:42 pmPlain old twisted pair cable would work the best. Most apartments are small enough that it would be trivial to string a little cable along the edge of the floor. If that won't work, 802.11 would work great if the frequency assignments were distributed the way cell phone towers do it, but most people won't understand how to.

author: SeanB
author_rank: Super Contributor
timestamp: May 26, 2012, 06:38:03 am
content: Power line devices are basically radio transmitters, there is no way a mains cable will act as a waveguide at those frequencies. You can operate them with one connected to a battery and an inverter, with a 5m long cord to provide an antenna.

author: G7PSK
author_rank: Super Contributor
timestamp: May 26, 2012, 09:05:43 am
content: I have used homeplug equipment for years, The wife wont let me rip the floors and walls to lat cable. Te RSGB has a campaign against them as they cause interference, But as I don't work short wave it does not bother me and I am so far out in the sticks that it should not bother any one else. The signal from the homeplug wont get past the meter as that has a coil in it also any other inductance in the line stops them dead.

author: RJSC
author_rank: Regular Contributor
timestamp: August 23, 2012, 11:21:39 pm
content: I have my lab on a garage separate from the house.Currently I have Wi-Fi 802.11n with antennas on the roof of each building, but it seems the 2.4 GHz band is crowded from neighbors devices and is gets slow. Yes, I've checked antenna alignment, etc...The garage gets its power from the house, and the floor between the buildings is concrete, so I cannot dig to install a CAT6 cable.I'd like to try one of those 500 mbps Homeplug modems in the hopes for it to match 100BaseTX ethernet at least, but I have something to sort out first:Short Power Outages are quite frequent arround here, so, both my IT gear at the house (router, roof wi-fi AP, server, etc) and almost my whole lab (PC, lighting, Oscilloscope, Signal Generator, DECT phone) are on a UPS (one for the lab, and one for the IT equipment at home).Is there a way to couple HomePlug modems to the power line, such as some kind on transformer or capacitive coupling so that I can keep them powered during an outage by the UPS and still couple the signal on to the mains wiring?They should at least provide an external power connector to the HomePlug modems so that we could power them from a plugpack on a UPS or a battery and they would continue to send the data trough the dead mains during an outage.Does anyone have a teardown of any Homeplug modem for us to evaluate the possibility of powering all the logic from an external source?Maybe all the networking part is powered from a floating switching power supply and then the signal is coupled to the mains wiring trough a transformer or capacitor.I'm unemployed and don't have the money to risk buying a kit just to teardown and see if they can be powered from other source isolated from the mains.

author: NiHaoMike
author_rank: Super Contributor
timestamp: August 24, 2012, 01:57:16 am
content: It should be quite easy to rewire the power supply to an external source. Or you can make adapters to make them operate well over an unused phone line.http://hackaday.com/2012/04/18/ethernet-over-telephone-wire/But before you try that, if there's an existing coax line between the garage and the rest of the house, you can try adapting the WiFi to that. Or you can make some "cantennas" by drilling a hole in an empty tin can and sticking the antenna in about halfway.

author: RJSC
author_rank: Regular Contributor
timestamp: August 24, 2012, 03:04:25 am
content: Cantennas will be no good. I already have a set of 7 dBi patch antennas.There is no phone line running also. The phone I have is a DECT (Digital Enhanced Cordless Telecommunications) wireless phone with its bas station inside the house.If I can crack them open and provide a separate power supply, I don't know if they'll work fine trough a dead mains cable of if like X10 they sync to the power waveform and only transfer data on zero crossings, therefor requiring the line to be live.

author: gxti
author_rank: Frequent Contributor
timestamp: August 24, 2012, 03:07:33 am
content: You're using two patch antennas between the garage and house, which are close enough for a cordless phone to reach, and the interference is too strong? Something else is wrong.

author: RJSC
author_rank: Regular Contributor
timestamp: August 24, 2012, 03:23:16 am
content: It works reliably but I only get a real throughput of 24 mbit (file transfer at 2.6~3.2 MB/s) over 801.11n (theoretical 300 mbps) from my server.It's the 2.4 GHz band which is crowded.It's 300 MBps PHY rate, but it is half duplex at it must carry 802.11 headers, it must have time slots reserved for networks sync packets, SSID broadcast, etc. Also, there are other devices on the same network, and other networks on the same band, so, to transmit it has to wait for a clear time slot when no other device (mine or from other network on the same channel) is transmitting.The DECT phone works on a dedicated 1.9 GHz band (1900~1920 MHz).

author: NiHaoMike
author_rank: Super Contributor
timestamp: August 24, 2012, 04:17:31 am
content: You could try 5GHz. It might be cheaper than PLC.Those PLC adapters probably don't sense zero crossing, but if they do, it should be pretty simple to spoof it with a 60Hz oscillator and some cheap 433MHz wireless modules to send it across.

author: T4P
author_rank: Super Contributor
timestamp: August 24, 2012, 12:48:13 pm
content: And then there's the horrible mains noise cheap PLC adapters cause due to the lack of filteringHere's my story, i was having massive issues on my F-connector cable modem (Hybrid Coax Types) with connection and disconnection togetherSo i decided to ring up my ISP, we tried many methods1) Replacing the very aged Splitters (25 of them 1 on each floor)That didn't work2)They went up with a spectrum analyzer and they discovered somebody's homeplug was inposing a shitload of noise on both the hybrid coax network and on the mainsWell they installed a big fat filter as clearly the homeowner wouldn't budge the homeplug3)Discovered modem's gone entirely berserk after the noise issue after some probing by them they told me the modem's reciever is shot so they gave me a new oneSo yes it can be really annoyingTry 5GHz WiFi, even if it means buying a 200 buck router, it's still cheaper than going PLC and the possible issuesIt isn't so much of a concern to me as i'm not so far away from my router, maybe 10meters away?

author: M. András
author_rank: Super Contributor
timestamp: August 26, 2012, 04:34:36 pm
content: i never used thes powerline devices and it wouldnt work in my house cos we have 3 phase coming from the utility and its wired on the idea of splitting the load to the 3 240v line cos the utility breakers are only 16A each so i had to share the load between rooms and the kitchen non of them are in the same phase. best solution for me was to buy a whole box of cat5e cable and rewire the old wiring as it had some defects. the router is capable of wifi communication simultaniusly on both 2.4ghz and 5ghz but i dont like it always reduced speed cos some interference in the area wish i wonder it would be better to buy shielded cat 6 cables. i didnt care to drill out some walls ethernet cable is only 5-6mm in diameter, no need for password protection

author: SeanB
author_rank: Super Contributor
timestamp: August 26, 2012, 07:23:38 pm
content: Trust me PLT will work across phases, much better than X10 does ( and X10 is designed to not radiate unlike PLT), you probably could get reliable connections between 2 houses next to each other if they share a common power line. There would be enough coupling in the cable to do so, and enough leakage past the meter.

author: M. András
author_rank: Super Contributor
timestamp: August 27, 2012, 04:56:45 pm
content: hmm good to know. do they work beyond surge protectors too? but i still trust my cables in the wall for the network communication. as for powerlines in this house if i could legally rewire the whoel house to the entry point i would have done it 5 years ago atleast almost 30 years old aluminium cabling with more than questionable connections and craftmanship.

author: SeanB
author_rank: Super Contributor
timestamp: August 27, 2012, 05:42:08 pm
content: PLT are basically a low power ( compared to a high power like 1kW) sub 1W broadband transmitter, which uses the mains wiring as a random length long wire antenna, with some matching so as to get RF energy into it, and a receiver that can use the same antenna to abstract some of that energy. Only reason they do not have much mutual interference with each other is because they use both frequency and code diversity, with them doing channel hopping and using a robust code to correct low levels of error in the transmission.Of course they will be a problem, only way to stop them is to take a neon transformer ( magnetic one) and make a Jacobs ladder - broadband high power (150W) RF noise source, very effective at blotting out up to the FM broadcast band nearby.

author: M. András
author_rank: Super Contributor
timestamp: August 27, 2012, 07:24:43 pm
content: hmm there is a mobile broadcast array 500m from me i wonder what could block thatand how many years would i get for doing that. i did not know that they are basicly radio transmitters. i thougt they send the signal over the cabling.