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Networking The Internet Technology

First Ceiling Light Internet Systems Installed 179

Posted by timothy from the how-the-gov't-will-control-your-mind dept.
An anonymous reader writes "We last heard about LVX's LED ceiling light optical communication system in December, and now news has broken that the company recently implemented the technology at several city offices in St. Cloud, Minnesota. The LVX/ceiling light system is capable of transmitting data at about three megabits per second, which is about as fast as a residential DSL line. It works by placing light-emitting diodes (LEDs) in a standard-sized light fixture. This then transmits coded binary messages to the special modems attached to computers, which also respond via light waves."
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First Ceiling Light Internet Systems Installed More

First Ceiling Light Internet Systems Installed

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  • The return of the infra-red access point, even if its not infra red this time around same bad concept.

    • Why is this a bad idea again? It's not overly speedy but it's plenty fast enough for almost any sort of office use.

      • Re: (Score:2)

        by tftp ( 111690 )

        Why is this a bad idea again?

        1. Install one or a couple of 802.11 access point; requires one power adapter and one (or zero, if WDS is used) Ethernet cable per AP. Everyone in the office can then access the network using 802.11 adapters built into most laptops and in many desktops. Get up to 54 Mbps link speed.
        2. Rip up your ceiling and route hundreds of cables to hundreds of IR transceivers there. Buy one IR modem for each computer, connect with more wires. Test the configuration. Get a few Mbps link speed.

        • Why is this a bad idea

          Because the WiFis cause the cancers! I learned this on the internets and from the city council of San Fransisco.

          • Why is this a bad idea

            Because the WiFis cause the cancers!

            Across the whole electromagnetic spectrum, it's visible light and it's immediate neighbors that seem to cause me the most measurable harm.

        • Re: (Score:2)

          by aXis100 ( 690904 )

          Have you ever installed an access point infrastructure to cover more than a few users. Let me assure you, your WiFi plan would fail HARD on any sizeable installation - there is just too much overlap and too few channels to cover large areas well. Let alone halving your bandwidth straight up with WDS.

      • It works 99% of the time, but the first time you get direct sunlight shining directly into the receiver, you're screwed. (This does occaissionally happen to satellite and other radio receivers.)

    • Re: (Score:3, Insightful)

      by icebike ( 68054 )

      The return of the infra-red access point, even if its not infra red this time around same bad concept.

      Well presuming the developers are not total idiots, lets give them the benefit of the doubt and assume they at least encourage WPA2 or something.

      In a closed room, at least you can be assured your transmissions aren't seeping thru walls as with regular WiFi.

      Even in an windowed room or public space, assuming the use of the above mentioned security, what is the difference in using light as opposed to radio waves?

      Other than the slow speed of this early version, and its line of sight restriction, what causes you

      • Re: (Score:2)

        by Nikker ( 749551 )
        Maybe I'm just a bit dense but why would you need a 3 or even 10mbps solution like this in a professional setting when I can get better reliability and performance off of a cat3 cable and off the shelf NICs?

        • Re: (Score:3)

          by geekoid ( 135745 )

          No maybe about it.

          This is cheaper infrastructure, easier to set up, MORE secure the Wi-Fi and 3 mbps is fine from most office needs.

          The cat3 cable and router require an whole wired infrastructure all the way to the desk.

          This does not. I can put up a temporary area and have people on the network without worrying about hard ports address, wiring, and several other issues.

          You know, there is more to setting up an enterprise wide infrastructure then there is to your panty ass home network.

          • Re: (Score:2)

            by Nikker ( 749551 )
            So this solution is somehow more secure than WIFI/RF although you don't mention how. Easier to setup but you would have to buy new adapters for each client and support them rather than the built in WIFI already present in pretty much all mobile devices. On top of it all provides less bandwidth then 802.11b. I admit I'm sold where do I sign?
            • Not having to run cables for every computer in the building is huge cost savings, both now, and in the future - those cables won't have to be ripped out and replaced with fiber in 10 years.

              Even doing a place up with WiFi requires expensive controllers, and so on - this is merely another wireless standard in the sea of wireless standards.

              Why are you so crotchety?

              It also doesn't sound like it suffers from the radio receive/transmit weakness, where a wireless device can only be listening or broadcasting

              • Re: (Score:2)

                by Nikker ( 749551 )
                I know it's a cool new toy I'm just saying I don't see how it is much better than WIFI. It's not like you won't have wires and controllers connecting all these lights and since you are going to have to replace your lights to have this work I don't see where the cost savings are going to be. As far as having to run fiber to each desktop maybe for a room of engineers but as far as the other 95% of the employees are going even with an entire floor running thin clients 1 or 10GB Ethernet and a good switch wil
                • Won't know unless we try!

                  The important thing is that it is different - what about a place that has lots of RF interference? Or you want each room to be partitioned?

                  Installing WiFi properly is not cheap, and it's entirely possible this will be a competitor.

                  My point about fiber is that as time changes, so do standards - fiber is overkill now, but who knows what will be transferring over the network in 10 years?

                  I mean, 128k ought to be enough for everybody, amiright?

    • This can use much higher output power, as it's the room lighting which you want to reach all areas of the room anyway. A drawback though is that the duty cycle has to be near 100%, otherwise the room lighting would dim. That has to cut into bandwidth.

      • A drawback though is that the duty cycle has to be near 100%, otherwise the room lighting would dim. That has to cut into bandwidth.

        Use non-visible light spectrum and adjust your regular lights so that they doesn't bleed into the non-visible range. Just because it's included in the light fixture doesn't mean it has to provide your lighting.

      • Re: (Score:3)

        by aXis100 ( 690904 )

        There are encoding algorithms that guarantee 50% duty cycle, and you then overrate the lighting power. Problem solved.

    • It's true that IR was slow and cumbersome, but damn was it useful for small-file transfers, and most implementations were a LOT less cumbersome than, say, the simplest bluetooth.

      There are several possible advantages to a concept like this.

      First, light is a lot harder to intercept unless you can see it. Light cannot penetrate walls. For those applications where you are afraid of RF being intercepted by ne'er-do-wells, using light is pretty brilliant (OK, my only bad pun in this post, I promise. Maybe). A

      • Re: (Score:2)

        by icebike ( 68054 )

        Third, for those with some sort of sensitivity to RF (or perceived sensitivity), you're flooding them with, well, light.

        Genius!!

        Hang some totally non functional blinking lights on the ceiling and tell all the Birkenstock whiners complaining about WiFi sensitivity that you've eliminated the problem just for them.

        Quick, does anyone have Ron Popeil's phone number?

      • Third, for those with some sort of sensitivity to RF (or perceived sensitivity), you're flooding them with, well, light. At much lower intensities than the light fixture is already putting out. If they're concerned about exposure to that, allow them to wear a fedora at work. Problem solved.

        What about people with light sensitivities? Generally fluorescent lights aren't to bad when placed in pairs, but when you get odd numbers of light tubes and flickering, that does seem to cause trouble for some folks.

        • Re: (Score:2)

          by plover ( 150551 ) *

          The blinking of fluorescent tubes is no faster than 120 Hz, as that's how often each zero crossing of the 60 Hz powerline frequency happens. I suspect the annoying visibly blinking fluorescent light fixtures have some flaw that makes them light up only on the half wave, at 60 Hz. 60 Hz is near, but certainly not beyond the upper limit of human perception. So yes, many people are going to be sensitive to certain fluorescent lights flickering.

          These LED systems will be blinking the lights at rates fast enou

      • Re: (Score:2)

        by hitmark ( 640295 )

        "It's true that IR was slow and cumbersome"

        it does not have to be:
        http://irda.org/displaycommon.cfm?an=1&subarticlenbr=102 [irda.org]

      • you provided the best use cases i've seen for this tech, but aren't the people who whine about exposure to RF also the people who can detect the blinking of florescent lights? i think just as many people are going to complain about these lights giving them migranes and hypnotizing them.
    • Sounds very one-way, thus inappropriate for normal LAN use. On the other hand, there are quite a number of successful grocery store systems that use similar methods to change the value of smart price display tags. Although they do it by pulsing the normal fluorescent lights overnight (don't want to drive the customers mad). LED's could do the same thing faster, and would likely scale better as a result.

  • My office's ceiling lights started flickering recently. Have they been upgraded with this system, too?

  • Troubleshooting this would be ... difficult. (Score:5, Funny)

    by Aussenseiter ( 1241842 ) on Thursday January 13, 2011 @04:09PM (#34868098)
    "Sir, are there three green lights on the modem?"

    "Hang on, let me climb my ladder."

    (crashing noise is heard in background)

  • It is not first (Score:4, Insightful)

    by arivanov ( 12034 ) on Thursday January 13, 2011 @04:10PM (#34868110) Homepage

    First was IBM Zurich 30 or so years ago with IR on the ceiling as a connection method

    Then there was the IR profile for WiFi. 802.11b at 1Mbit actually has an optical option. However as there is nobody doing it any more so there is no standards compliant kit out there.

    Otherwise it is a very cool idea for a number of applications. There are places where you just do not want radio for a variety of reasons. Light is much less likely to cause interference and is much easier to keep "contained" so it is not eavesdropped on.

  • BOFH vs. The Ficus tree (Score:5, Funny)

    by ArcadeX ( 866171 ) on Thursday January 13, 2011 @04:16PM (#34868232)
    User: My network won't work.... Tech: Move your ficus tree so it's not blocking the light again...

  • In other news... (Score:3)

    by thrill12 ( 711899 ) on Thursday January 13, 2011 @04:18PM (#34868256) Journal
    the newly formed company Fee@Ces inc. announced a breakthrough in encoding binary data in output stools.
    "This is great !", an employee of the Sewer City company announced proudly, "Now when I want to convey messages to my colleagues, I simply visit the bathroom and the technology takes care of the rest. And, using our technology of a series of pipes, we can even use this to work from home.".
    Fee@Ces did mention that inputting data back to users is a bit harder, as a spokesman said: "Users will need to properly operate the machinery involved to read out the processed stool messages. Failure in doing so can give unexpected results.". It was unclear at the time of writing what the 'unexpected result' meant, as the spokesman had to quickly take care of an 'accident' he had at the bathroom himself.

  • There are four lights!

    • That was a memorable episode. Loved Picard's and the Cardassian interrogator's roles in it. Also loved the end when Picard says he actually thought there were five lights. Great two-part episode.
  • Given the plethora of proven connectivity options out there, I can't envision a scenario where I would chose this implementation over others. From TFA they talk about saving energy with the LED lighting system, but couldn't you by a cheaper LED lighting control system without their "value added" data transmission tech added to the cost?

    • Given the plethora of proven connectivity options out there, I can't envision a scenario where I would chose this implementation over others. From TFA they talk about saving energy with the LED lighting system, but couldn't you by a cheaper LED lighting control system without their "value added" data transmission tech added to the cost?

      Yes. However, so much of the cost of an LED system is in the LED's themselves, and so little is in the hardware that's running the driver, that adding extra functionality to the driver has marginal added cost to the overall package. Moreover, businesses and particularly government purchasing offices are *screaming* for managed light systems that they can remotely monitor and shut down per-unit. That means networking to the light, with control over whether it's on or off, is already included in such a des

  • Insecure (Score:3)

    by Avatar8 ( 748465 ) on Thursday January 13, 2011 @04:26PM (#34868408)
    I seem to recall when modems with lights were still in use, that a video tape of the flashing lights on the modem could be slowed down enough to read the stream of bits. Granted 3mb/s is a great deal faster than 56kb/s, but video technology is faster now, too.
    I would presume there is encryption on both ends, but I see a small IR led "bug" left on top of a computer, cube wall, file cabinet, etc. serving as a middle man pickup of the stream while it is decoded on the other end.

    • If you can get physical access to the facility, they're screwed anyway. Your "bug" could be RJ-45 based and cover a lot more of the network.

      I think the major point is that containing light is a lot easier than containing the current 802.11x frequency ranges. Light cannot penetrate walls. It can only penetrate air, glass, and other transparent or translucent surfaces.

      Of course, electrons on copper are even more secure, assuming your hacker doesn't have building access. Anything that emits any form of rad

    • It's not really any different than Wifi except that you will probably get a bit more security by direct firing the light. (I assume it's using encryption.)

    • I seem to recall when modems with lights were still in use, that a video tape of the flashing lights on the modem could be slowed down enough to read the stream of bits. Granted 3mb/s is a great deal faster than 56kb/s, but video technology is faster now, too. I would presume there is encryption on both ends, but I see a small IR led "bug" left on top of a computer, cube wall, file cabinet, etc. serving as a middle man pickup of the stream while it is decoded on the other end.

      Doesn't have to be modems. You can recreate network traffic from reflected flashes from a network switch [scientificamerican.com], although this report [cnet.com] claims that it is, probably, restricted to 56kbps modems, not 10/100mbps ethernet cards.

    • You would need a very special camera to catch such high-speed toggling of the LED. Normal video 24-30 frames per second. That's well below the 300 baud of even early modems and you need at least twice the switching frequency to get the data (Nyquist). At 3MB/s they would need to be encoding a lot of bits per switch to get in range of a video camera. Some specialized sensors can do 1 million frames per second but their buffers can only handle 100 frames at a time.

    • I could be mistaken here, but I think that's probably an urban legend. Even assuming that you were using a 300-baud modem that could show a nibble at a time on 4 parallel LEDs and that the LEDs were updated on every single bit, that would still be a potential flicker rate of 75Hz. That would be impossible to catch on any consumer-grade camera, although some specialized equipment could capture it. At 14.4kbps, it would be completely impossible with any video equipment that I'm aware of. At 56kbps forget abou

    • How is this any different from any other wireless network system out there? Encrypting the signal would work just as well with the bonus point that people don't accidentally stumble across the network and instead need to make an effort to actually physically locate and establish a line of sight to the station.

  • It's easy to see that any system requiring special light fixtures and modems for each PC will be far more expensive than simply setting up a wireless access point or two for each floor of a building. This wouldn't even just be a one-time cost, but would apply as part of regular maintenance - which is easier, to swap out a router, or to bring in contractors to replace all of a company's light fixtures?

    A system like this could really only be practical where conventional wireless can't be used for some reason

    • Re: (Score:2)

      by aXis100 ( 690904 )

      You cant run a whole floor of 50 - 100 stations with "a wireless access point or two". Even limiting the number of users per AP, you find very quickly that there is not enough non-overlapping channels nor physical seperation to tesellate properly - let alone the interference from your neighbours - resulting in very poor bandwidth per user and a poor quality of service.

  • You could even use this for inter-building communication. Stick and transceiver on an outside wall, with the opposite building doing the same. For improved reliability increase the intensity and use a laser instead.

    As other people have mentioned the technology is not that novel, but the fact they are actually try to move the technology forward is of interest, since there are scenarios where a more limited signal transmitting solution actually has it uses. Security being one of them. Sure any device in the r

  • But what about the people who say that fluorescent tube lights flicker at a frequency that gives them headaches etc? Oh boy there will be office workers complain these lights give them migraines, cancer, the lot.

    Plus the occasional crazy telling us that the lights were speaking to him....

    • Just don't tell them about it. They'll be fine.

    • Re: (Score:3)

      by LWATCDR ( 28044 )

      Well if it is transmiting 3mbs then it must be modulated at no less then 6 mhz. Nobody can see a 6 mhz flicker so it should be a none issue.

      • Re: (Score:2)

        by h4rr4r ( 612664 )

        It should be but the loonies will claim it hurts them somehow. These are the same folks that claim Wifi gives them cancer or whatever.

    • There's some truth to the fluorescent light complainers... old magnetic ballasts run the light at 60Hz, which can create noticeable flickering (you can see it easier if you look with the side of your vision).
      Modern electronic ballasts run at very high (30khz+) frequencies and so don't have this problem.
  • Is there any risk of epilepsy [wikipedia.org]? I'm guessing there isn't (since it's way too fast), but the right combination of bits might be able to do it, though probably only if intentionally rigged. The point is that this technology makes that possible, perhaps also untraceable.

  • Magnetic Radio Waves (Score:5, Informative)

    by Catskul ( 323619 ) on Thursday January 13, 2011 @05:56PM (#34869698) Homepage

    "It is better than traditional wireless communication since systems such as WI-FI, 3G Networks and Bluetooth all require magnetic radio waves."

    Oh, so that's the difference between light and other parts of the EM spectrum. Here I always thought it was just wave length...

    I'm glad that science reporter was there to help educate the public. >:/

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