back to article Disney's light-bulb moment: build TCP into LEDs for IoT comms

Since lights are everywhere, and LED lamps are The Way of The FutureTM, it makes sense that they be used for communications. Now, boffins working for Disney Research have taken LED-based comms a step further, adding a Linux TCP/IP network stack to a consumer lamp. Their work, published here, pushes visible light communication …

  1. Voland's right hand Silver badge

    You do not need more than 1kbps

    For most true IoT applications 1kbps is more than sufficient. Sesors, alerts, commands, etc do not need more.

    Neat idea and thankfully (to IBM) not particularly patentable as this was this method of networking was developed extensively in one of the European labs in the 60-es and abandoned due to inability to go beyond 20-30kbps.

    1. jake Silver badge

      Re: You do not need more than 1kbps

      Abandoned, RH of Voland? I dunno ...

      I still use X-10 kit to control miscellaneous bits & bobs.

  2. Anonymous Coward
    Anonymous Coward

    Bravo, IoT internet connectivity in a small space, when can we talk security or is that a silly question these days? Do I just connect a routing light bulb to my network and hope for the best?

    1. Anonymous Coward
      Anonymous Coward

      yeah, just hope your neighbours don't have similar light bulbs and it will all be fine!


    Prior art?

    Flashing LEDs? Surely the humble TV remote was there decades before this. Also, I remember that there was a toy in the market that received cues of what to say from the TV by registering slight brightness variations on the picture from a sensor in the eye of the toy?

    Headache, because rapidly flashing lights will do this to you in a long run.

    1. Warm Braw Silver badge

      Re: Prior art?

      Well, certainly, TCP/IP over IrDA didn't even need inventing, it just kind of works.

      It's a bit harder with visible light sources since you want the light sources still to provide unimpaired illumination and there are lots of potential sources of noise (and cross-talk). And as a matter of general principle, the more robust the protocol, the slower the communication speed.

    2. Alan Brown Silver badge

      Re: Prior art?

      "Headache, because rapidly flashing lights will do this to you in a long run."

      Only if flashing at something less than 80Hz

    3. Tcat

      Re: Flickering?

      Others have at least got binary transmission done via household LED lights. The pulse pattern for even 1 kilobit/sec would be far beyond the human eye to detect the flicker.

  4. Phil O'Sophical Silver badge

    How many IT techs does it take to change a lightbulb?

    Will we now have to wipe the storage on our lightbulbs when we recycle them? This really sounds like another over-the-top, insecure, solution looking for a problem.

    1. ntevanza

      Re: How many IT techs does it take to change a lightbulb?

      Never underestimate humanity's capacity for inventing problems in response to a solution.

  5. Anonymous Coward

    And we need this for..

    what exactly?

    1. Dan 55 Silver badge

      Re: And we need this for..

      It's Disney so it's going to be an IoT princess.

    2. M7S

      Re: And we need this for..

      Its all a plot by the secret world government.

      There used to be warnings on TV where heroes like No. 6* or the ladies in that allergy research clinic in OHMSS would be hypnotised by a flashing light (often with a spinning spiral pattern added).


      Now these things are going to be installed in our homes and controlled by the lizards.

      Strangely such warnings seem to have vanished from our screens in recent decades. It's a conspiracy I tell you, a conspiracy!

    3. Zimmer
      Big Brother

      Re: And we need this for.. communication, Teddy!

      .I Always Do What Teddy Says.... (1965..H Harrison)

      1. Anonymous Coward
        Anonymous Coward

        Re: And we need this for.. communication, Teddy!

        Which Teddy? Teddy Ruxpin?

    4. Anonymous Blowhard

      Re: And we need this for..

      Freaking out people who can't receive WiFi in their brains?

      Also, do I have to leave the lights on all the time? How will my alarm clock connect to the Internet when I'm asleep? This doesn't seem to have been considered!

      1. Pascal Monett Silver badge

        Re: do I have to leave the lights on all the time?

        Of course not, you'll have an app on your mobile to dim them to almost-darkness, while the TCP-IP stack retains power for transmitting.

        All you need to do is install the app, agree to it siphoning your GPS, storage and camera data and log on automatically to Facebook and Twitter, and you're all set to live in the golden age of damn, where's my phone so I can shut off the damn light ? My 2,438 friends need to know I shut my light off.

  6. Your alien overlord - fear me

    Well during a storm, my sitting room lights dim/flicker when lightning strikes upto a few miles away. I don't want something suddenly geting a signal 'kill all humans' just because of the weather.

    1. hplasm Silver badge

      What make you think-

      a) The flicker is due to the lightning? *

      b) The flicker is not due to the 'kill all humans with lightning' signal?

      * That's what they want you to think...

  7. Steve Crook

    Who knew?

    Team rodent have a research division?

    1. Martin Summers Silver badge

      Re: Who knew?

      Yeah they like to keep a low profile as people think they're a bit Mickey Mouse.

  8. /\/\j17

    Screw all this pointless IoT junk. It's 2015 so why can't I wire my house with CAT6 and power my LED light bulbs using Power Over Eithernet???

    1. John Robson Silver badge


      Had to go and check, but PoE can provide >30w over cat5, slightly more over cat6 - so I think this is a great idea. My kitchen is the only room that would take more than that - but I can easily provide it with two "zones".

      Of course I can't sanction ripping my existing wiring out just yet...

      Of course it also make dimmable lights etc, much easier to deal with...

      1. Anonymous Coward
        Anonymous Coward

        " PoE can provide >30w over cat5, slightly more over cat6 - so I think this is a great idea"

        Don't forget the voltage drop on longer cable runs, and the fact that LEDs are typically quite a reactive load. Even if you've got a couple of zones, you'd need to think about the capabilities of the PSU that's producing the power to go over the ethernet. Much easier to simply use a proper LED driver and real wires.....

        1. Alan Brown Silver badge

          "LEDs are typically quite a reactive load"

          You're confusing the bridge rectifier and capacitor that many cheapies use off AC mains with what happens when you feed them with steady-state DC.

    2. jake Silver badge

      @ /\/\j17

      "and power my LED light bulbs using Power Over Eithernet???"

      You can! Mains-net, USB-net, whatever-net ... Either-net will power LEDs nicely :-)

  9. jake Silver badge

    So I guess ...

    Disney "engineers" actually live in the "Toon" world?

  10. Anonymous Coward

    Oh great!

    Now I've got to worry about my light bulbs plotting behind my back.

    1. This post has been deleted by its author

      1. This post has been deleted by its author

        1. Anonymous Coward

          Re: Oh great!

          Not harsh. An amusing follow-up.

  11. Mage Silver badge

    LED Optical WiFi

    Been demonstrated some while ago at 1Gbps. Of course that was Line Of Sight only.

    This is purely developmental stuff. No research or invention involved. 1Kbps comms has been on LEDs since 1970s, not with TCP/IP till late 1990s.

    To actually control LED lamps, without ethernet via the power, surely Bluetooth or WiFi or an IRDA or even RC5 IR remote would be better.

    I've implemented encryption on a carrier compatible with RC5 IR receivers using Manchester encoding over OOK at 38KHz. That's all you need for a light controller.

    1. Graham Cobb

      Re: LED Optical WiFi

      I found the earlier paper on the challenges of making the comms work with real consumer LED light bulbs (while allowing them to still function as effective lamps) to be more interesting than the "gimmick" of including an OpenWRT implementation in the bulb. Although I take exception to their claim that "such bulbs cannot run out of power as they are supplied by the grid": what happens when the light is turned off (during all daylight hours)?

      Clearly the challenges are very different from using a dedicated LED for comms. It will be interesting to see if they can increase the switching rates in real light bulbs up to much higher speeds than the roughly 1KHz they are using today.

  12. Electron Shepherd

    I like the idea

    It runs Linux, so if I can install Apache, MySQL and PHP on it, I can have a LAMP stack running on a lamp!

    1. Steve Davies 3 Silver badge

      Re: I like the idea

      But will it use 'systemd'?

      coat with a linux firewall guide in the pocket.

  13. Zog_but_not_the_first Silver badge

    With one tap on his smartphone...

    Every light in the house was extinguished....

  14. Ragequit


    Internet of creepy things invading our children's bedroom.

  15. Missing Semicolon

    Never mind the RaspPi..

    I always thought that these little Atheros chips would make great dirt-cheap computing nodes for little projects. One of those boards with the wireless antenna on, and a few GPIOs should cost less than £10.

    Unfortunately, as you'll find out from reading the OpenWRT site, the manufacturers aren't keen on the general public hacking with their chips, so data and sampes are hard to come by.

  16. Unicornpiss Silver badge

    Who needs that much innovation?

    I can't wait to get pwned by a rogue light bulb that had a virus added to its firmware.

    Will there be a clapper forthcoming that also connects to your wireless network? It's hard enough now to get the devices we currently own to connect properly to our networks and stay connected. I'm sure it will be amusing if your router dies and you can't turn on the lights in your home. Will there be TCP/IP-connected wall switches then? What will this do to the cost of lighting, reliability, and ease of recycling? I don't think I'll find it amusing having to pair a new lamp to my network, or having the one stubborn bulb that wont turn on or off, and naturally that will be the one at the top of the vaulted ceiling.

    I could see how this would be useful for commercial buildings that currently use elaborate controllers to manage the lighting, but for my home, I prefer to reach for the familiar wall switch that I know will work every time.

    1. Captain DaFt

      Re: Who needs that much innovation?

      "I prefer to reach for the familiar wall switch that I know will work every time."

      My dad used the SON system.

      "Son, will you turn on the light, it's getting dark in here."

      "Son, will you turn down that damn stereo!"

      "Son, while you're up, change the channel, and get me a beer."

      He loved the system; me, not so much.

      1. Unicornpiss Silver badge

        Re: Who needs that much innovation?

        Not quite related, but my coworker has a "DAD" retirement plan. (Die at Desk)

  17. Craig 2 Silver badge

    What if I want to use Windows to manage the light in my house?

    1. VinceH Silver badge

      That only works in dayligh... oh, sorry, just spotted the capital W.

  18. W Donelson

    Gee, in my childhood it was eggs on the front door, and toilet paper in the trees...

    Times change.

  19. Spaceman Spiff

    And WHAT could possibly go wrong with this scenario? Are they out of their minds? My opinion, absofragginlutely! Just because you can do something, doesn't mean you should. Would I buy one of these? Not if you held a gun to my head!

    1. Will Godfrey Silver badge

      You might not have a choice.

      1. Steven Roper

        Re: You might not have a choice

        Yep, like with smart TVs - try and get one that isn't these days. Or incandescent light bulbs. Or phones that are just phones. There seem to be 5 stages to this process:

        1. A new version of something, now with built-in camera and microphone complete with monitoring phone-home profiling, comes out as an expensive, hard-to-get luxury.

        2. The new version becomes trendy as all the hipsters line up to buy it.

        3. The new version becomes commonplace and cheap.

        4. The old version becomes an expensive, hard-to-get luxury.

        5. The new version becomes effectively mandatory because the old one gets banned for "environmental" concerns or disappears since they aren't selling (because they were deliberately made expensive and hard to get.)

        Voila! New lifestyle-data-slurping version in every home, car and pocket!

  20. Mark 85 Silver badge

    Disney and IoT....

    OMG... <runs screaming from the building>

    Next will be toys with these LED's built in... and who knows how many parents will be screamed at by their sprog for one or more.

  21. zen1

    Bright idea? Getting my coat...

  22. Stevie Silver badge


    All your pix of giant mouse are belong to lightbulb.

  23. Mike 16 Silver badge



    --Will there be a clapper forthcoming that also connects to your wireless network? --

    Here in the former land of the free, we already have a Clapper, but he says they aren't actually "collecting" anything from that network. Not until they get around to reading it, that is. Sort of like a cat that's not dead until someone does a little parallel construction and gets a warrant.

    Anyway, now we know why incandescent bulbs are illegal and CFLs make a right hash of anything RF.

  24. DougS Silver badge


    I'm sure they'll say "its a light bulb, there's no need to worry about security" but it sure will be annoying when someone hacks into it and every light in your house, including the ones in your bedroom, start flashing at 4:30 AM.

    IoT is the most ridiculous hype about nothing. Can't believe anyone thinks that light bulbs need to be individually addressable.

  25. Queasy Rider

    LED's: Not all they are cracked up to be

    Sitting at a traffic light today, I noted that the green led light had about a third of its led elements black already. This light was installed less than a year ago. I hope the city bought the extended warranty because they went whole hog with led.

  26. BigFire

    Vinge's Localizer

    First thing I think of is Vernon Vinge's Localizer from A Deepness in the Sky. Perhaps not that level of usefulness yet, but first step.

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