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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."
From the summary:
This then transmits coded binary messages to the special modems attached to computers, which also respond via light waves."
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"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/
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...
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"...
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 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."
REAL enterprises use subspace transmissions.
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.
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.
"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.
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