A core part of the hacker mentality is the desire to test limits: trying out ideas to see if something interesting, informative, and/or entertaining comes out of it. Some employees of Andrews & Arnold (a UK network provider) applied this mentality towards connecting their ADSL test equipment to some unlikely materials. The verdict of experiment: yes, ADSL works over wet string.
ADSL itself is something of an ingenious hack, carrying data over decades-old telephone wires designed only for voice. ADSL accomplished this in part through robust error correction measures keeping the bytes flowing through lines that were not originally designed for ADSL frequencies. The flow of bytes may slow over bad lines, but they will keep moving.
How bad? In this case, a pair of strings dampened with salty water. But there are limits: the same type of string dampened with just plain water was not enough to carry ADSL.
The pictures of the test setup also spoke volumes. They ran the wet string across a space that looked much like every hacker workspace, salt water dripping on the industrial carpet. Experimenting and learning right where you are, using what you have on hand, are hallmarks of hacker resourcefulness. Fancy laboratory not required.
Thanks to [chris] and [Spencer] for the tips.
Yes, but how well does ADSL carry over a wet noodle?? That’s what I want to know.
Yes, and also two slices of pizza. :)
The pizza works as a hub.
Will that be a 8 slice hub ?
4. I’m on a diet
Will It Blend / Hydraulic Press Channel, but for testing ADSL across various absurd mediums.. hmmmmm
Spaghetti (Fettuccini, Hair ) or Ramen or Egg Noddle or Udon or Soba ?
I use pappardelle for maximum bandwidth.
ADSL will carry over a single wire if the wind is in the right direction. It will also carry over lines so bad you can’t hold a voice conversation.
Be interested to see someone hack up a point-to-point ADSL line as I’m not sure it can be done with consumer gear and it’d be handy as a cheap way of getting data down more than 100yds of Cat5 – especially with 4 pairs to play with.
You can get p2p adsl modems off the shelf…
I’ve heard of wire fences being used.
Didn’t ranch hands once have portable phones that they would connect to the fence, so they could phone the central building? IIRC, they also would drive a spike into the dirt to act as ground.
Tut Systems used to do a demo at trade shows over two parallel lengths of barbed wire.
I used to work in a small rural town where the telco still had some customers in the back country with phone service lines that were a single wire strung along a fence, and a honking big ground spike at the house, and another by where the one wire hooked into the POTS service X miles away. Back in the ancient times when phone service was installed out there, wire was expensive and a way to save 50% on wire was happily embraced by the phone companies.
Mostly dialup on those was barely good enough for getting and sending email without attachments, or *very patient* web browsing. ISTR that one of them did get up to 14.4K connection, but I dunno if it ever got anywhere near that transfer speed.
I once had a copper voice line with a very bad 60Hz hum. ATT would never admit a problem (“Your line checks out”, “But there’s a horrible hum”, “I’m sorry sir, I can’t hear you because of the hum, can you speak up”)
I ordered DSL, partly to force them to fix the line. DSL worked fine without any repair!
Had that problem too, the reason was old phone. It was working good for 20 years, then started to hum.
I took a known good phone out to the junction on the pole, with the house wiring disconnected, and still had the problem (old house, where they never installed a modern demarc box)
I can confirm that one wire is enough to have it connecting and slowly working, although I have no idea how it can still be fine (the ground path is a few km long with a terrible impedance).
I also tried to use all the 4 pairs in a terrible telephone cable (ADSL + VoIP + 2 half duplex Ethernet across a house).
Funnily, the DSL line gets disconnected when the VoIP phone rings, so the phone stops ringing. At least negative feedback is good at stabilizing systems.
Hacked Homeplug adapters = cheap and very fast option for private “DSL” links.
SDSL and SHDSL boxes are available and do that.
Few months back we pushed 8.6mbs symmetrical over some twinlead along with 60VDC over a short 400m path with junkbox SHDSL boxes.
it’s just a shame BT can’t manage to get it to work properly over the few hundred metres from the exchange to my house, than again I guess it’s not a miracle technology
That few 100 metres could have been in the ground for 50 years though, the old copper (and partly aluminium) UK network is very crusty.
That said, Openreach culture is “just bodge it up quick and run away”, most of the engineers hate it as they’d far rather do it right, replace crusty old cables etc. than run round fire-fighting.
I wish I had better photos and videos of the Anything But Ethernet contest, which one year involved a T1 running over barbed wire…
Better not show this to any Time Warner execs…
I’ve suspected that they already use something similar.
ADSL works too with only one wire. But very slowly. It happened to me last year.
Send it over pwm style modulated esla coil. Zerp wires.
Now pass it through a line of people all holding hands. We hands, technically would have low enough resistance. The reflection would be awful no doubt.
Just wait a few minutes till everyone gets clammy hands, the sweat should have enough salt get a solid connection & maybe minimize reflections.
Please don’t give BT Openreach any more ideas of how to degrade service and save money.
Make it work over red tape
FYI, they also tried thread as well but that proved unsuccessful.
See the original twitter feed from the engineer who actually did this:
https://twitter.com/0x47DF/status/939165734709624833
Argh, wasn’t expecting that (all I wanted was a link, not some malformed magic-insert-thing in the comments)
Now I wanna know what the ascii code for magic sparkles is
it’s not in the ascii character set, but apparently it’s in unicode since version 6.0:
https://emojipedia.org/sparkles/
Haha just look at this silly misshapen thread.
How long can one practically extrude a pair of wet noodles?
I still have to service fax units, thankfully, they aren’t stand alone, but integrated into the entire copier/printer/scanner ecosystem. But, VoIp faxing still has challenges that I wish would GO AWAY. It was a mess trying to get 33k faxing on copper, but on VoIp, unless the ATA box is located close to the phone jack, has T.38 installed is a MESS! I’d rather deal with copper sometimes. Pushing data down a 20,000 pair cable with low S/N crosstalk can be a challenge.
We even had one trunk line in town that after ever storm, would get wet because it had a leak and the pressurization would be zero. They kept a liquid nitrogen bottle on the line FOR YEARS. Recently, I noticed the bottle was gone and about a month later, we had an at&t tech in our office and I asked him, and he said “oh, they finally got around to fixing the leak and pressurizing the line again”.
Any idea of the speed?
My internet is 1.7Mbit/s on a good day. Can I have the 3.5Mbit wet string instead please?
My internet download speed is about 1Mbit/s nominally. Can I also have the wet string?
Circa 1998 I worked in a town where out in the countryside there were still a few farms with phone lines that were a single bare wire strung along a fence on porcelain insulators. The other half was connected to a metal stake driven about 5 feet into the dirt. Connection speed for dialup varied depending on the weather, perhaps 14.4K when it was really dry but not too dry or the ground side would get worse. IIRC power for the customer equipment had to be provided with a transformer at their end, so if there was a power outage they had no phone. The lines dated back to the days of magneto charged batteries in the phones, and party lines.
It is not so much the resistance in the wire, but loose connections and cross talk. Try a loose connection with a lot of static. It will still work, but it will have to work harder.
I may be showing my age here but I remember using telebit trailblazer modems and you could talk on the phone over them and they would just slow down. In fact we got a ROM upgrade for them because the first generation of them did not have a way to agree to hang up and the remote modem would sometimes hang on to a disconnected line for minutes before giving up.
ADSL works, even on a disconnected phone line that a phone doesn’t work.
Three years ago, my telecom finally came to install fiber lines for the whole apartment. I think they forgot to plug a copper wire back to the distribution board when they’ve done their work, I only found out that a day later when I picked up my phone and heard nothing. I measured the phone line with my DMM.
It was 0 (zero) volt, absolutely. Somehow the Internet was still working. The modem was struggling to transmit and error-correct the data, and the bandwidth severely degraded to ~256kbps with high latency, but it was still enough for web browsing and chatting on IRC.
How could my ADSL work on a disconnected phone line? My best guess is because of the fact that ADSL uses AC signal, if a single wire in a twisted-pair was disconnected, the AC signal can still partially transmitted to the other end and be decoded, provided the modems on both ends shared a common power ground, the earth.
But only my phone line was disconnected accidentally, I think the disconnected wire was not ground but the “hot” wire. How could a signal travel through solely a ground wire is beyond my understanding of the telephone system. The polarity doesn’t matter for modern phone lines?