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First Ceiling Light Internet Systems Installed
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."
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.
From the summary:
This then transmits coded binary messages to the special modems attached to computers, which also respond via light waves."
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
"Sir, are there three green lights on the modem?"
"Hang on, let me climb my ladder."
(crashing noise is heard in background)
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.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Because RF can go through walls and the whole point of visible band communication is privacy.
Sigs are too short to say anything truly profound so read the above post instead.
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 to call it a "bad concept"?
Sig Battery depleted. Reverting to safe mode.
User: My network won't work.... Tech: Move your ficus tree so it's not blocking the light again...
An I.T. motto in the hands of an idiot is a dangerous thing...
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.
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Transmitting the data through the air, you mean like WiFi and cell phones do all the time? Too bad we don't have a way to scramble the data in a way that makes its contents inaccessible unless someone has the "key"...
How does the light get outside without windows? Inquiring minds want to know.
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.
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?
Just one more reason not to use Windows, I suppose.
"National Security is the chief cause of national insecurity." - Celine's First Law
Real Enterprises know how to deal with the security issue of Wi-Fi.
The Kruger Dunning explains most post on
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.
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.
The Kruger Dunning explains most post on
Vernacular uses "light" to mean "visible light". Please move along.
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). All your worker drones are in soulless, windowless cubicles, so there's little to no chance of light escaping the building in readable form. A Pringles can and a few minutes with a Yagi antenna tutorial will yield someone lots of RF lovin', and shielding all that costs serious coin and it's easy to miss an exit vector for RF.
Second, there are 11 US-licensed RF channels with plenty of crosstalk opportunity between adjacent channels. If your worker drones are down in cubes, you could install one of these in every other light fixture and reach every worker drone with their own discrete light channel with no crosstalk.
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.
Obviously the easiest, fastest, and most secure answer is to run sufficient copper to give everyone a network plug (then secure them so your wired traffic is encrypted and no random idiot can plug a sniffer into a port and start watching traffic flow, or plug a non-approved bit of hardware into the LAN and start seeing what resources they can access). But if you want reasonable-speed wireless in a computer-dense environment, light might work pretty well.
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
I can see how it would be a problem at night
I'm not even sure it would necessarily be a problem at night. I'm pretty sure these things would be programmed with maybe a 45-degree cone, and the client computers would be sending their signals back from down inside Cubicle Canyon. You might be able to get some reflection off the ceiling tiles and cubicle tops, but that's going to be a very weak signal.
Plus, there's no real indication of what frequency these use, but it seems to me that it'd be pretty simple to just put up a filter for that frequency on any outside-facing windows. With RF, there's always a chance of a crack in the shielding that has to completely and utterly surround the building allowing leakage. With light, it can only exit through the windows and openings. You know where your gaps are, and can fix them a lot more easily.
Wired is, as many have observed, faster and more secure. But if you need wireless, I could see lightwave wireless as being a pretty viable solution. Especially if you throw some WPA2/AES-level security over it, and maybe illuminate your outside-facing window surfaces with a few well-aimed LEDs sending continuous gibberish.
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
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.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
REAL enterprises use subspace transmissions.
Consider me wrong, the article says it's visible, but it's at a refresh that human eye's cannot detect. Serves me right for not reading either article. ;)
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
So "Real enterprises" never use WiFi?
Real enterprises treat it as a second class network, but all desktops are generally still on a wired network.
They also generally have you use an encrypted VPN even if you're on an internal WiFi.
The irony is that all but the most criminally negligent IT administrators would apply military-strength cryptography to their WiFi links, but allow data to traverse the wired connections in the clear, which means that the wireless link is substantially more secure!
One of the biggest vulnerabilities in any large office building is the wired network. It's trivial for an attacker dressed in a suit to simply walk in, sit down at an empty desk, plug in, and start doing packet captures. Switched networks provide minimal protection, thanks to DNS cache and ARP cache poisoning attacks and the like.
You'd be amazed at how ignorant typical IT administrators are of the risk. I've heard ridiculous things like:
"But you need to fill out a form to get network access!"
- Only if I follow the rules. Nothing stops me from physically connecting.
"You need an AD account to connect to the network!"
- They're thinking of network shares, but the exploitable vulnerabilities are at the IP network layer.
"Your computer is not a member of the domain, it can't connect!"
- That's largely irrelevant, once you have a user account, practically everything is accessible even from a machine that's in an untrusted workgroup.
These aren't from rare isolated incidents either, I hear one of those three almost every time I sit down at a new customer as a consultant. System administrators live in a fantasy land of imagined security.
You think all the switch ports are on? You think they will talk to just any mac address? You think the IDS will not notice your ARP poisoning?
Sure wired networks are a risk and there are ways around what I mentioned, but you are clearly talking about the follys of Windows Operators. Please do not call those folks System administrators.
Yeah, I'm new here.
I've only been around long enough to learn two things:
1) how to evaluate Slashdot Poster ID numbers.
2) how to detect posers calling themselves a "data center Jesus".
Sig Battery depleted. Reverting to safe mode.
i agree, it's little different from wifi, but i don't understand why it's better than wifi? It doesn't sound cheaper to install. It's definitely not faster. It doesn't work through drywall. It doesn't sound like it's friendly to portable systems.
the TFA says it's better because it uses visible light rather than magnetic radio waves. It doesn't give any reasons why thats better. Though i imagine visible light is less prone to certain kinds of interference, its far more prone to the interference of walls. Plus, the days of microwaves disrupting wi-fi seem to be over. Unless you have an MRI machine next to your desk, you probably have a reliable wifi signal.
I guess it could be some kind of homeopathic new network transport. It might make all those people who are scared of wifi feel better. that may be true, but in my experience, the bands of the electromagnetic spectrum that do the most damage to me seem to be closest to visible light.
"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. >:/
Im not here now... Im out KILLING pepperoni
i agree, it's little different from wifi, but i don't understand why it's better than wifi? ... It doesn't work through drywall.
I don't claim to understand this system completely, but that sounds like a feature to me. Crowded apartment building? This gives an alternative to a saturated wifi network.
Sewage Treatment Facilities - "Our duty is clear."
This is a good point. You deserve an upmod. No signal interference is a good thing. And being able to limit the signal to one enclosed area instead of broadcasting to god knows where is also good. Security through obscurity.plus no interference... I like it.. An attacker would have to be in the room to have a go... provided your blinds were closed and the signal was, as has been pointed out, encrypted
"No fear. No envy. No meanness." Liam Clancy
There are encoding algorithms that guarantee 50% duty cycle, and you then overrate the lighting power. Problem solved.
It's a corporate environment. The use of Windows is mandatory.
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