So what happens when 2 people in the same room want to use the internet? Do they get each others websites (awkward!!).
Meet ELIoT – the EU project that wants to commercialize Internet-over-lightbulb
A consortium of European organizations has launched ELIoT, an EU-funded project that hopes to develop commercial applications for visible light communications. The project’s primary concern is Li-Fi – a method of short-distance data transfer that relies on the light spectrum and fancy LEDs rather than radio frequencies, …
COMMENTS
-
-
-
-
-
Wednesday 31st July 2019 18:26 GMT martinusher
So what happens when 2 people in the same room want to use the internet?
Same thing happens with wireless. That's what protocols are for.
Most people seem to have forgotten that the original use for 802.11 was allowing computers to communicate using infra-red light. This interface was common on 90s laptops and was the reason for WiFi having its 'ad hoc' mode of operation that didn't use an access point as such.
-
Thursday 1st August 2019 20:11 GMT Michael Wojcik
Re: So what happens when 2 people in the same room want to use the internet?
This interface was common on 90s laptops
And very popular on the Palm Pilot, which for a short time was nearly ubiquitous among gadget fans in the US. I recall family get-togethers where groups of cousins would be cheerfully beaming contact details at one another.
I still have a Palm Pilot Titanium lying around somewhere (I may see if I can get it working for a little retrocomputing fun one of these days), and I believe I still have at least one working laptop with an IrDa interface.
-
-
-
-
-
-
Thursday 1st August 2019 20:11 GMT Michael Wojcik
Re: Dumb reg readers
A bit of research suggests LiFi developers are also using, or working on, at least WDM and OFDM as well.
And pretty much by definition LiFi uses spatial multiplexiing, since it's confined to line-of-sight. Every room is its own segment.
But that's the thing with multiplexing: you start with dividing in one domain, and pretty soon you're dividing in half a dozen. It's just too much fun.
-
-
-
-
-
-
Wednesday 31st July 2019 09:59 GMT Francis Boyle
Re: 'Unlightly' to happen.
Not if you live in a one of these. For some reason they're big in japan.
-
-
-
Thursday 1st August 2019 11:49 GMT ibmalone
Re: 'Unlightly' to happen.
I'd think the technology should deal with that, depending on your switching speed. In a room with a single lightbulb you can still see in the shadows due to scatter. This leads to multi-path dispersion in fibre-optics and smears out the signal (it's better regarded as phase velocity effect, but hey-ho), but distances within rooms are short and likely you can adjust sensitivity to get the strongest-path signal only.
-
-
Wednesday 31st July 2019 10:25 GMT Dr Dan Holdsworth
Re: 'Unlightly' to happen.
Actually, we're steadily heading in this direction already. 2.4 GHz wifi penetrates walls quite well, 5 GHz has better bandwidth but much less range, and 5G mobile telephone signals are even higher frequency and penetrate solid objects even less well.
Skipping a section of the EM spectrum and moving on to near infrared or visible spectrum is just a logical next step, which would once again increase the possible bandwidth and would allow/force more transceivers to be put in close proximity.
-
Thursday 1st August 2019 08:55 GMT 96percentchimp
Re: 'Unlightly' to happen.
IIRC 5G is being employed from 700MHz up to the high GHz range, depending on the environment and use case. It's not tied to a slice of bandwidth, and in time the operators will probably want to re-use their current 3G/4G spectrum for 5G, just as they have with some of their 2G bandwidth.
-
Wednesday 31st July 2019 13:51 GMT Mage
Re: 'Unlightly' to happen.
It's been around since the 1980s. It's basically line of sight and more expensive to install than WiFi Airpoints. Also it was about 2003 was when laptops stopped including optical communications?
It's very niche, so few laptops, tablets & phones will include it. Also efficiency for generation of optical signals is pathetic compared to 800MHz to 6GHz (Mobile & WiFi).
-
Wednesday 31st July 2019 15:13 GMT Jellied Eel
Re: 'Unlightly' to happen.
It's been around since the 1980s. It's basically line of sight and more expensive to install than WiFi Airpoints. Also it was about 2003 was when laptops stopped including optical communications?
People of a certain age might remember the BBC's Micro show, complete with blinking box in the corner of your TV screen that you could read with a light pen/sensor to dowload code.
-
Wednesday 31st July 2019 18:08 GMT Brewster's Angle Grinder
Re: 'Unlightly' to happen.
"It's very niche, so few laptops, tablets & phones will include it. Also efficiency for generation of optical signals is pathetic compared to 800MHz to 6GHz (Mobile & WiFi)."
All phones, many tablets, and some laptops have optical sensors. In the modern parlance they're termed "cameras".
Angel because their halos would provide interference.
-
-
Wednesday 31st July 2019 17:52 GMT Daniel von Asmuth
But soft what Li-Fi through yonder window breaks
"Li-Fi is not susceptible to electromagnetic interference"
....except maybe the light of our old sun. Our eyes would notice when a LED starts transmitting... A spy could tap of LiFi signal through a window.
Why not use IrDA or something that works better under water.
-
-
Wednesday 31st July 2019 08:41 GMT Pascal Monett
So we are going to have flickering streetlights everywhere
Are streetlights going to become Internet hotspots then ? Or will the streetlamp just relay data from its neighbors ?
Are you going to be able to pirate a streetlamp signal and send anything you wish in an untraceable manner ?
And when you've reached the last streetlamp, where does the signal go then ?
I think there is still a lot to think of concerning this technology.
-
Wednesday 31st July 2019 09:03 GMT simonb_london
Re: So we are going to have flickering streetlights everywhere
Probably the exact opposite. We will no longer have flickering street lights because the current 50/100 Hz flicker is due to rubbish LED driving circuitry. If it has to be an advanced driver that pulses the LEDs at a much higher frequency than anyone can see then the 50/100Hz will disappear in the process.
-
-
-
Wednesday 31st July 2019 09:06 GMT Jedit
Re: First radio, now light...
Boo this man. (Then optionally upvote him.)
I think my main concern with this technology is how to stop the signal being blocked by, for instance, someone walking between the transmitter and the receiver. But I'm sure that's been thought of, I just haven't read around the subject yet.
-
Wednesday 31st July 2019 12:03 GMT Balding Greybeard
Re: First radio, now light...
@Jedit, me thinks that line-of-sight requires ceiling mounts like most offices do today for WiFi. Question is, how many LiFi transmitters are required? And then I think of my Sammy TV remote, it uses infrared transport which bounces off just about anything.
Too often, I pickup the remote without looking at the orientation and try changing channels. When I realize the channel numbers are going down rather than up I figured the signal is probably bouncing off my great beer belly.
-
Wednesday 31st July 2019 13:35 GMT Doctor Syntax
Re: First radio, now light...
The thing about your IR remote is that the actual signal on the IR carrier is quite low frequency. What happens when you ask it to transmit a GHz signal?
You'd be sending out a pulse of light about a foot long (Grace Hopper used to hand out nanoseconds - pieces of wire about a foot long). It would be OK with a direct line-of-sight signal dominating the reflections. Block that and the various reflections of your nanosecond pulses will arrive over a period of tens of nanoseconds.
-
Wednesday 31st July 2019 13:57 GMT Mage
Re: First radio, now light...
You'd struggle to do 0.002 Mbps on an IR remote system. Manchester encoding at less than 1 kbps using 38kHz OOK of the IR. Makes it quite immune to noise and allows high sensitivity. You'd need about 10,000x power for same performance from ethernet speed optical communications.
-
-
-
Wednesday 31st July 2019 15:21 GMT Teiwaz
Re: First radio, now light...
I think my main concern with this technology is how to stop the signal being blocked by, for instance, someone walking between the transmitter and the receiver.
There was an episode of Max Headroom : Twenty Minutes into the Future, where Bryce was experimenting with high power lasers for communication purposes
So high power, they could supposedly bisect anyone walking through the beam...
It wouldn't stop anyone, but they wouldn't do it again.
-
-
-
Wednesday 31st July 2019 09:08 GMT BinkyTheMagicPaperclip
'Interference free'
It might not interfere with the Li-fi communication, but it might cause interference in the first place. I only buy decent (Philips) LED bulbs, as the no-name ones interfere with other equipment.
It's also going to be a pain when the bulb dies, the lifetime is always predicted based on limited usage per day and perfect wiring. If your wiring is less than optimal, expect the lifespan to be dramatically less.
-
-
Wednesday 31st July 2019 12:15 GMT Balding Greybeard
Wired is the Best
I once rented space in an old meat warehouse converted into a multi-tenant office building. So many neighbors, so many WiFi signals. Equals too many collisions. Equals no throughput.
Mounted 1” conduit on the wall, with 2-CAT-5 drops by every desk, equals wonderful throughput. And multi-line phones at every desk.
-
Wednesday 31st July 2019 09:19 GMT steelpillow
IrDA
IrDA does pretty much exactly this with infrared. According to Wikipedia, "IrDA was popular on PDAs, laptops and some desktops from the late 1990s through the early 2000s. However, it has been displaced by other wireless technologies such as Wi-Fi and Bluetooth, favored because they don't need a direct line of sight and can therefore support hardware like mice and keyboards. It is still used in some environments where interference makes radio-based wireless technologies unusable." I couldn't have put it better myself (although IrDA lends itself to dark humour better than Li-Fi does).
Li-Fi would seem to have much the same issues, topped with an established rival in the few environments where it is appropriate.
-
Wednesday 31st July 2019 09:51 GMT Keith Oborn
Re: IrDA
From my memory of IrDA the problem was desperately short range - you had to put the two little black panels within an inch or two of each other. So presumably very limited power. However, it's evident that this *can* be done: almost all consumer electronic remotes are IR. OK, data rate is trivial. However, they are still quite directional, but that may be by design.
Basically sounds like a bright idea. But if we all have to buy new LiFi light fittings (ant bets?) not so good.
I can see advantages in shared spaces: hospitals, shopping centres, etc, where there is usually fixed lighting from multiple sources and often quite a bit of electrical noise. WiFi range can also be a problem.
HMM: we all forget these technologies have to be bi-directional. Does than mean my laptop (phone!) has to have a light bright enough to be seen by a detector 100m away? What happens when the phone's in my pocket?
-
Wednesday 31st July 2019 10:14 GMT Anonymous Coward
Re: IrDA
Either your memory or your hardware was faulty. Psion 5 to HP printer (LaserJet 6?) worked from several feet away. Psion to phone was usually inches away, but only because I wanted the phone within easy reach. Getting any of these to work reliably with Windows was another matter entirely, and I suspect this is where IrDA's reputation for unreliability came from.
-
Wednesday 31st July 2019 10:29 GMT albertfandango
Re: IrDA
> But if we all have to buy new LiFi light fittings (ant bets?) not so good.
True, but for new buildings or major refurbishments this is less of an issue.
> Does than mean my laptop (phone!) has to have a light bright enough to be seen by a detector 100m away?
This was explained to me a while back: Data transmission is achieved by modulating the light levels very quickly (rather than simple on/off). It can therefore operate in very low light levels (invisible to the human eye) albeit with a bandwidth penalty. Still, this would allow the system would operate in a “dark” building.
> What happens when the phone's in my pocket?
Nothing :) Seriously though, I don't think personal mobile devices are likely to be viable for this kind of technology, but I could be wrong...
-
-
-
-
Wednesday 31st July 2019 23:51 GMT Mike 16
Alternative uses
A friend was curious about the "universal remote" capabilities, and stumbled across a source of fun.
Seems that some (many?) of those scrolling LED signs used in many businesses are controlled with some sort of IR comms. This was during the period that there were bank branches, and enough folks who used them to have lengthy queues.
As usual for "connected thingies", there was no security, so he would while away his time in the queue by changing the signs on the wall behind the tellers to something like
"Ask about our .1% 30 year mortgages".
-
-
-
-
Wednesday 31st July 2019 11:43 GMT juice
Re: IrDA
> According to Wikipedia, "IrDA was popular on PDAs, laptops and some desktops from the late 1990s through the early 2000s
I remember going to some BT Expo thing back in the late 90s, and they were demo'ing some fancy City Trader desk with an I/R network hookup - there was a big "drainpipe" tube at the back of it, which was meant to communicate with a sensor in the ceiling.
These days, it's all about nanosecond transactions and any humans still in the process are pretty much just window dressing for Skynet, so the idea of using any wireless technology is out the window. Still, it did look impressive :)
-
Wednesday 31st July 2019 13:55 GMT GlenP
Re: IrDA
IrDA had its uses but could also be a pain in the proverbial.
Many years ago I used it to connect the fairly ancient laptop to the Nokia phone, due to incompatible voltage levels the alternative serial cable only worked if the laptop was on mains and fully charged. It did mean I could dial in to the office and run the month end processing from my tent but there was a huge issue with electromagnetic interference to the signal - caused by the sun! Had to put the phone by the laptop and cover the connection.
Sat on a training course a few years later we discovered the many corporate standards didn't include having the IrDA port on the same side of the laptop so my machine and the one belonging to the person next to me kept trying to communicate until we built a mini-wall between them.
-
-
-
Wednesday 31st July 2019 10:33 GMT albertfandango
On the LiFi kit data can still be transmitted at light levels invisible to the human eye, so presumably if/when you flicked a wall switch the relevant bulbs would switch to an invisible light/low bandwidth mode as required.
Although I suspect mere mortals wouldn't be allowed anywhere near lightswitches in this kind of building-of-the-future.
-
Wednesday 31st July 2019 16:08 GMT Arthur the cat
What happens when someone leaves the room and turns out the light....do all of the devices go off line?
The system modulates the dark. What, you've not heard of dark solitons?
-
-
Wednesday 31st July 2019 10:10 GMT TeeCee
Obvious drawback.
The bulbs will, inevitably, be astonishingly expensive, the rewiring for the infrastructure to support them won't be cheap and you'll have to do every bloody room....including the bog and the cupboard under the stairs.
This is better than plonking a wireless access point in one place how exactly?
-
Wednesday 31st July 2019 10:32 GMT Steve K
Hmm - what if the lights are off....?
Presumably this means that you will need your lights on all the time, unless you only use WiFi at night.....
In many office/public building environments I imagine that this will not necessarily be an issue, but how about other use cases (streetlights, home)
-
Wednesday 31st July 2019 10:35 GMT albertfandango
Re: Hmm - what if the lights are off....?
As above: data transmission is achieved by modulating the light levels very quickly (rather than simple on/off). It can therefore operate in very low light levels (invisible to the human eye) - albeit with a bandwidth penalty - which would allow the system would operate in a “dark” building.
-
-
Wednesday 31st July 2019 10:50 GMT Loyal Commenter
I can think of several issues
Presumably not all insurmountable, but off the top of my head:
Limited by line-of sight (or reflection)
No interference from EM radiation? What about the fact that light is EM radiation? Will receivers be 'blinded' by oversaturation from things like camera flashes, lightning strikes, or other rapid changes in ambient light levels? What about moths and other flying insects?
Eavesdropping - better have your blackout blinds and curtains shut if you don't want your neighbours across the street eavesdropping (okay, I know this is no worse than Wi-Fi, but still...)
Backhaul? How will this work? Will it need special light sockets with wired network, or will it use Wi-Fi for backhaul? If Wi-Fi, what is the point - you're already using the Wi-Fi bandwidth, so why not use Wi-Fi directly? If wired, then will I need to rip all the wiring out from my lighting circuit and replace it? You could use IP over powerline, but that is pretty useless when lighting is on a separate circuit to your power sockets (with a breaker that has a different current limit).
What is the expected lifespan of one of these special bulbs? I know LED bulbs last a lot longer than incandescent ones, but I'm willing to bet they'll still burn out - either the LEDs or the control circuitry.
-
Thursday 1st August 2019 03:14 GMT Balding Greybeard
Re: I can think of several issues
@Loyal Commenter, you got to give power over Ethernet another try. I have 4-Netgear Powerline 2000s, Ethernet over power devices. Brings Ethernet to all 3-levels of my townhouse. And even use it to Connect my 3-node Google WiFi nodes. Google WiFi initially barked about the speed, but once settled in, I have consistent throughput to my wireless and streaming wired Hulu devices. No interference from neighbors, no glitchy performance. I walk around the house with iPad in-hand seamlessly transitioning from Google node to Google node.
-
-
Wednesday 31st July 2019 12:42 GMT maffski
Research farming in the EU
It's taxpayers money. Specifically 5.9 million euros of taxpayers money. https://cordis.europa.eu/project/rcn/220023/factsheet/en
'...Main project goals are to provide an open reference architecture for the support of IoT in the lighting infrastructure, build consensus reflecting the best architectural choices, contribute to standardization of lighting and telecom infrastructures in IEC, IETF, IEEE and ITU-T and provide a roadmap for IoT until 2022 and beyond...'
5.9m euros to attend some conferences, draw up a powerpoint and write a spec. no one will ever use.
To quote Milton Friedman 'I’m sure going to have a good lunch!'
-
Wednesday 31st July 2019 13:45 GMT Loyal Commenter
Re: Research farming in the EU
To be fair, if you want people to draw up decent standards for things, you have to pay them in more than magic beans, and if you want a reference architecture, then you're going to need hardware prototypes, and such things don't come cheap.
The whole point of innovation is that sometimes it goes nowhere. That money isn't wasted though, because lessons are learned, knowledge is gained, and the dead-ends are made up for by the other things that do go somewhere. It's pretty much the definition of research - if you already knew what the result would be, it wouldn't be research...
-
Wednesday 31st July 2019 14:30 GMT RayG
Re: Research farming in the EU
I agree research is speculative and has to accept funding some things that turn out to be dead ends... so there's a good case for writing off the cost of the previous round of work on this subject. Throwing more after it isn't really taking a risk for a chance of innovation, it's safely progressing something we already know isn't a bright idea. Seems like it could be an example of the sunk cost fallacy - a favoured choice of dim bulbs.
-
Wednesday 31st July 2019 15:43 GMT Loyal Commenter
Re: Research farming in the EU
I suppose it all comes down to whether you can find a convincing use case for it that isn't already covered by other technologies (e.g. Wi-Fi, or a length of good ol' fashioned CAT6e). I'm struggling to think of one, possibly some environments where you need to keep the RF noise really low, or you don't want signals leaking through walls (but don't want wires, or a faraday cage). It's certainly goig to be niche, but might find military or covert uses.
-
-
-
-
-
Wednesday 31st July 2019 12:02 GMT mark l 2
I am really struggling to think of many practical uses for LiFi other than the very limited use in environments where you can't use WiFi or Ethernet. As LiFi will be restricted to individual rooms since it relies on line of sight it is less practical than WiFi so can't be used for mobile devices without drop outs when you move from one room to the next. And even for static devices which never move your going to need to ensure that you maintain consistent line of sight with nothing blocks the sensors.
-
Wednesday 31st July 2019 12:07 GMT UberMunchkin
I expect the biggest roadblock for adoption is that a lot of us techies will see the 'Internet of Things' part of the statement and immediately file them under "Garbage ideas for garbage technology". The IoT is a mess of unsecured and poorly thought out rubbish that anyone with half a brain will avoid for a long time.
-
Wednesday 31st July 2019 13:06 GMT Anonymous Coward
(singing tunelessly to self, spray cans in pinny pockets and duster in hand)
"Don't mind me, deary," (sprays desk, wipes)," just freshening the place up" (sprays lemon-scented air-freshener)
"My! Them's some fruity words you know, there, dear! What's gone wrong with your internet, then?" (sprays desktop computer, polishes..)
-
Wednesday 31st July 2019 15:03 GMT Richard 51
Old technology given a new lease
My father worked on this technology in the 70's at STC (a defunct telecoms company). Light is electromagnetic radiation, just much higher frequency so to say there is less electromagnetic interference is plain wrong. The reason they dropped it was primarily that the amount of light pollution meant the noise levels were problematic and its of course line of sight, if people walk in front of the transmitter the signal can be lost. But I guess the frequency and modulation in todays implementation will mean these problems are less of a concern.
-
Wednesday 31st July 2019 15:24 GMT Uplink
One way?
OK, so you use lights to transmit data to the devices, which presumably will get quite of bit of the data through reflections. How do the devices send the data back to the light fixture? Signal shadows/eclipses are a lot more likely when you're hunched over your laptop.
I have this feeling we'll get a "dongle" that sticks out so it can see the light bulb.
-
Wednesday 31st July 2019 16:05 GMT LeahroyNake
Close the curtains
I suppose closing your curtains is much easier than getting WiFi security configured correctly, even if most home WIFI boxes are (or should be) secure by default.
Does anyone else remember having to use irda (or whatever its called, think back to when Nokia was the phone to have) to connect a mobile to their laptop.... Lots of fun that was lol
-
Thursday 1st August 2019 08:40 GMT Ittopgun
Bumpe r
I worked on line of sight transmission in the mid 60s where we ued a low powered laser as the carrier. With fibre optics now this could make a very useful secure way of transmitting large chunks of data without the fear of anyone listening in? Not a good idea as a substitute for WiFi but could have a future for short range Comms or long range secure fibre optic transmission?
-
Thursday 1st August 2019 13:15 GMT gnarlymarley
Li-Fi might work great in England, but not so much in the USA. England has the cloudy thing going on. In the USA, there is much sunlight (which makes solar panels a better option) that leaks through the windows. A lot of people use the windows instead of a light bulb. It would work great at night, but not so much during the daytime.
-
Friday 2nd August 2019 17:00 GMT Henry Wertz 1
how is it connected?
For me the reason for not using this is more practical... I don't have ethernet ports in my light sockets. And if I used ethernet over powerline (homeplug or the like), the speed of that is lower than 802.11ac anyway.
There are those hotels where they'll like hide an access point (and phone jack and ethernet jack) in a table lamp. Lifi would be easy to add in these cases 8-)