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1Gbps Optical Wireless Network Might Replace Wi-Fi

timothy posted more than 4 years ago | from the line-of-sight-and-bouncy-bouncy dept.

Networking 200

Mark.JUK writes "Pennsylvania State University has developed a new method of indoor Optical Wireless network that does not require a line-of-sight and runs at speeds of 1Gbps+. The system uses a high-powered laser diode — a device that converts electricity into light — as the optical transmitter and an avalanche photo diode — a device that converts light to electricity — as the receiver. The light bounces off the walls and is picked up by the receiver. Traditional radio frequency systems (Wi-Fi , WiMAX etc.) do not require line of sight transmission, but can pass through some substances and so present a security problem. Light, in a room without windows, will not escape the room, improving security."

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200 comments

Or, you could just use cables (3, Insightful)

ClosedSource (238333) | more than 4 years ago | (#30964588)

This is only going to work in the small area that the laser can get to, so cables might be a better solution.

Re:Or, you could just use cables (1)

itzdandy (183397) | more than 4 years ago | (#30964730)

If you considered this an open-air fiber optic cable (minus the fiber and the cable) then there may be a cost benefit over cables. Each cable requires infrastruction from jacks, in-wall cables, switch ports, etc while a whole room optical wireless could use a single switch port. Also consider that the price of these components could be very low. Diodes are typically not very expensive and a diode->serial USB could be made very cheaply though would not be gigabit speeds.

I think that for basic connectivity wireless is 'good enough' but this optical setup would certainly be more secure considering. Also consider that optical transmissions dont follow the same rules as microwave transmissions you could use as much of the band as you like to increase speeds even more.

Re:Or, you could just use cables (1)

TheRaven64 (641858) | more than 4 years ago | (#30964968)

If the hand-off is fast then it could be good. You'll need a base station in each room, but at that speed you can just mount them on door frames with an endpoint in each room and they can relay between the rooms.

Re:Or, you could just use cables (1)

mindstrm (20013) | more than 4 years ago | (#30965486)

You'd have little sensors, just like little antennae in wifi... but, say a call-center floor. Instead of running Cat5 everywhere, you just put a few transmitters and receivers around... possibly built into the monitors, and everything "just works"

Useless for me (5, Funny)

aBaldrich (1692238) | more than 4 years ago | (#30964606)

I like to shut the door of my room while watching my movies and other stuff.

Re:Useless for me (0, Redundant)

arndawg (1468629) | more than 4 years ago | (#30964652)

You mean LOCK the door so your mom won't walk in on you while watching porn?

Re:Useless for me (1)

mister_playboy (1474163) | more than 4 years ago | (#30964680)

My room doesn't have a door, you insensitive clod! :(

Re:Useless for me (5, Funny)

SteelFist (734281) | more than 4 years ago | (#30964976)

My room doesn't have a door, you insensitive clod! :(

Caught one too many times, I take it?

Headaches... (3, Insightful)

venkateshkumar99 (791435) | more than 4 years ago | (#30964612)

If the LASER is anywhere in the visual spectrum, the whole house could become a perpetual disco ;)

Re:Headaches... (1)

Shatrat (855151) | more than 4 years ago | (#30965606)

It won't be. It will either be 1310nm or 1550nm.
I doubt that anything lower than 1310 would be used due to increased attenuation of higher frequencies.
By the way 1310 is more than double the wavelength that you can see with your eyes, and if this thing is made with APD receivers then it will not be cheap.

wait... (1)

charlener (837709) | more than 4 years ago | (#30964618)

what if you open the door? Will internet leak out of the room?

I suppose a double door or, more entertainingly, a revolving door, could help with this...

Re:wait... (2, Funny)

Bromskloss (750445) | more than 4 years ago | (#30965280)

what if you open the door? Will internet leak out of the room?

I suppose a double door or, more entertainingly, a revolving door, could help with this...

Have a look at this. We're intercepting an electromagnetic signal in the terahertz range and it seem to have some kind of beating. I think we just might have found a pulsar!

Ah, and is it Useful? (3, Informative)

Oxford_Comma_Lover (1679530) | more than 4 years ago | (#30964620)

> Light, in a room without windows, will not escape the room, improving security.

Although at a cost? This system might be useful for Universities that need to provide wireless to a hundred computers in the same room, but it would be almost useless for homes and such, where one of the big reasons to go wireless is to avoid the need to rewire the house. To use a 1 Gbps signal, you'd need a hard-line to the room.

The other point is that for most applications, it's simply unnecessary to improve over the speed of modern wireless.

Still, there are a few niches where this would be useful, and it sounds like a really fun idea to develop.

Re:Ah, and is it Useful? (1)

phantomfive (622387) | more than 4 years ago | (#30964734)

Still, there are a few niches where this would be useful, and it sounds like a really fun idea to develop

I've been trying to think of the niches, and the obvious one is in security applications, but I don't see that as being any more secure than encrypted wireless. Is there really a use for this? Nice to know it's possible, I guess.

Re:Ah, and is it Useful? (1)

mindstrm (20013) | more than 4 years ago | (#30965506)

Absolutely - take a call center.. or any cube farm. No need to run ethernet cable everywhere... just some cheap well-placed sensors, and, unlike wifi, the leakage can be better controlled.

So the advantages would be

1) less leakage to other areas
2) speed

Wrong on one count (3, Insightful)

dreamchaser (49529) | more than 4 years ago | (#30964746)

The other point is that for most applications, it's simply unnecessary to improve over the speed of modern wireless.

Uh huh, and 640K should be enough for anyone, and there's no reason to go to broadband when a regular old analog modem is sufficient for most applications, and...well you probably get my point by now.

Re:Wrong on one count (2, Insightful)

Darkness404 (1287218) | more than 4 years ago | (#30964934)

...And does anyone ever get internet connections even -close- to the 54 MB/Sec of wireless G? If you are streaming media throughout a home its nice, but most people don't use their wi-fi for that, they use it for internet where the primary bottleneck is the internet service, not the wireless router.

Re:Wrong on one count (1)

twidarkling (1537077) | more than 4 years ago | (#30965010)

I use my Wi-Fi for that. If it's late, and I'm tired, I'll watch a movie on my laptop off my NAS, so then I can just close the laptop when I'm finally tired enough to drop off.

However, that means this new optical wireless is useless to me. The only application for home use I could see is keeping multiple devices connected to some data server in a home theatre set up, to minimize cables. I think this is something not even for enthusiasts, but for very specific situations, so Wi-Fi isn't going to be "replaced." Misleading headline at best, eh?

Re:Wrong on one count (1)

dreamchaser (49529) | more than 4 years ago | (#30965038)

I use wifi for multiple devices on my internal LAN; I wasn't even thinking about Internet. As for bandwidth, I get about 30 mb/sec now and I'm sure that will just keep increasing as well.

My point was there's no such thing as a technology that should not be improved upon for future needs.

Re:Wrong on one count (1)

Mad Merlin (837387) | more than 4 years ago | (#30965196)

...And does anyone ever get internet connections even -close- to the 54 MB/Sec of wireless G?

That's megabits, not megabytes. And no, you usually get perhaps half of the stated maximum speed with wireless, for wireless G that means ~25 Mbit/s, or ~3M/s, at best.

Re:Wrong on one count (1)

dgatwood (11270) | more than 4 years ago | (#30965498)

Either way, IIRC, the average broadband speed is still single-digit Mbps. So for most of us, Wi-Fi can still trivially saturate our upstream link.

Re:Wrong on one count (0)

Anonymous Coward | more than 4 years ago | (#30965286)

...And does anyone ever get internet connections even -close- to the 54 MB/Sec of wireless G? If you are streaming media throughout a home its nice, but most people don't use their wi-fi for that, they use it for internet where the primary bottleneck is the internet service, not the wireless router.

In many countries you can get 100 Mb/s Internet connections, which is about twice the 54 Mb/s (nee MB/s) connection speed of 802.11g. Of course with 802.11n that may help things a bit.

Though you're right, most people (sadly?) don't have that "problem".

Re:Wrong on one count (1, Informative)

Anonymous Coward | more than 4 years ago | (#30965296)

54 Mbit/s can carry 12 Mbit/s up and 12 Mbit/down, maximum. Or 24Mbit/s down and nothing up. Up + down == 24 Mbit/s.

And at least my internet connection is 100 down / 100 up Mbit/s. So I'd need uh... 8x 54Mbit/s wireless routers and some '30' channels to get that kind of throughput.

Not that 11n is much better. Would need 3-4 of those, too!

Re:Wrong on one count (2, Interesting)

TheRaven64 (641858) | more than 4 years ago | (#30965040)

640KB is enough for some people. 6.4MB is enough for a few more, 64MB for a lot more, 640MB for a lot of people. Each increment increases the things you can do. 64KB is enough for editing text. 640KB for rich text and small images. 6.4MB for larger images. 64MB for large raw images. 640MB for SD video. 6.4GB for HD video. 64GB for volumetric 3D images (the visible human dataset is around 40GB). 640GB for volumetric 3D movies. Are there things that 640GB isn't enough for? Almost certainly, but the number of people wanting to do them is relatively small. Far more people want to edit text than want to edit volumetric data.

In terms of network speed, 802.11n is fast enough to stream HD video. BluRay movies are at most 50Mb/s, while 802.11n has a theoretical speed of 300Mb/s and can get 50Mb/s in the real world quite happily. Are there uses where it's not fast enough? Sure, but not many yet. Eventually it probably will become common to do things that make 802.11n seem slow, but it isn't yet. The only reason why GigE was deployed in a lot of places was that it was as cheap as 100Mbit Ethernet.

I moved from 100Mb/s wired Ethernet to 802.11g because, for most uses, the convenience of not having to use a wire was more useful than the extra speed. From there, I'd rather move to 802.11n and have one access point for the house than 1Gb/s optical networking and need one in every room.

Re:Wrong on one count (1)

mindstrm (20013) | more than 4 years ago | (#30965520)

Exactly - wiring up an office building with Cat5 costs a fair bundle... and is fairly inflexible. Wireless is flexible, but too slow and leaks.

Give me a wireless signal that's easier to keep from leaking out of the room, and that operates closer to GigE, and it's an instant win all over the place... maybe not in your house, but in any business.

1gbps is extremely useful (1)

Sycraft-fu (314770) | more than 4 years ago | (#30964984)

If you have more than one computer, and that would be the sort of situation that this is targeted at (if you have only one you probalby have your cable modem plugged right in to it) 1gbps lets you transfer quickly between them. With 100mbps or lower, your limit is the network. Anything over the network is noticeably slower than something on your computer. Things can take a long time to transfer. However with 1gbps, the limitation is often as not something in your computer like the harddrive. Speeds over the network are near enough to local speeds you don't notice the difference. Copying something to a remote computer is as fast as copying it locally. It's very nice.

So sure, I have only 15mbps to the Internet. You could say for net access 100mbps is more than enough and be right. However I have a 1gbps wired network. That way my local systems can communicate extremely quickly.

Re:1gbps is extremely useful (0)

Anonymous Coward | more than 4 years ago | (#30965356)

"However with 1gbps, the limitation is often as not something in your computer like the harddrive."

New hard disks can transfer way past 1 Gbit/s, like Samsung F3 (measured some 160MB/s). For laptops, it's true for now - if they don't contain a SSD.

Re:Ah, and is it Useful? (1)

93 Escort Wagon (326346) | more than 4 years ago | (#30965216)

I don't particularly see the usefulness of this tech for single-room "computer labs" - running cable is not difficult and will almost certainly be far cheaper. Also, you're not really all that concerned with the visual appearance of cables in a computer lab.

Not to mention that (based on my group's experience anyway) university computer labs tend to be theft magnets, so you'd have the issue with people wanting to walk off with your optical router and/or the optical receivers.

As far as security goes... all of our computer labs have windows, so the signal wouldn't be confined to the room anyway.

Mirrors. (1)

Toze (1668155) | more than 4 years ago | (#30965546)

Funny thing about light. You can reflect it, direct it, quick rewrite it- er, anyway. It'll be like that scene in the Mummy sequel, only instead of mirrors, gold, and flesh-eating scarabs, it'll be mirrors, internet, and botnets. :D

Disco ball of internet! Woo!

Re:Ah, and is it Useful? (1)

nine-times (778537) | more than 4 years ago | (#30965938)

The other point is that for most applications, it's simply unnecessary to improve over the speed of modern wireless.

There's still video. IIRC, uncompressed 1080p/60 is roughly 3Gbps. Now you can still stream video without hitting 3Gbps, but then you theoretically lose quality and also you need more power to decompress the video stream on the other end.

Even ignoring the aspect of real-time streaming, people are buying/storing video at home, which even highly compressed can be several hundred megabytes per hour; if you want to copy those video files from one computer to another, you'll want some speed.

Re:Ah, and is it Useful? (1)

eiapoce (1049910) | more than 4 years ago | (#30966010)

The other point is that for most applications, it's simply unnecessary to improve over the speed of modern wireless.

Of course, also 640K ought to be enough for anybody!

Of course often the room *does* have windows. (1)

mrjb (547783) | more than 4 years ago | (#30964632)

It's only more secure if it implements the same security measures (encryption, key based access) as current wireless (okay, if the light is infrared it may be stopped by windows.

I don't think it will be a big contender for wireless though. The killer feature of wireless is that you don't have to drill holes in your walls to have network connectivity in the entire house. But if the network is optical, it will essentially be limited to the room where the base station is. Personally, I'd stick to my trusty old wires then. Reliable, secure, fast and low-cost, what more do you want?

Re:Of course often the room *does* have windows. (1)

that this is not und (1026860) | more than 4 years ago | (#30964662)

The killer feature of wireless is that you don't have to drill holes in your walls to have network connectivity in the entire house.

Wait and see. There will probably be a growth industry based around hanging mirrors at corners to transfer and reflect the light.

Re:Of course often the room *does* have windows. (0)

Anonymous Coward | more than 4 years ago | (#30964732)

What more do I want?

Which technology uses the least power?

security (3, Insightful)

wizardforce (1005805) | more than 4 years ago | (#30964674)

How many homes don't have windows? Of those homes, how often is it that there is a need to connect with a computer inside a closed room? Any system that can connect to a computer inside a closed room can also be connected to from outside the house. Any system that can't be connected to from outside the house also can not connect to a system with the door shut. The number of times the signal can bounce off walls would significantly affect the range of the system. So while a direct path between floors of a house may be 10 meters, the path through the house from the top floor going around everything that is opaque to the system might be 50-60 meters and quite possibly out of range.

Re:security (0)

Anonymous Coward | more than 4 years ago | (#30965238)

In the Netherlands, all furnished rooms are required to have windows - by law. For each 10 square feet of floor, there has to be 1 square foot of window. This applies for houses as well as office buildings. So this wouldn't work here. Though it would be much easier to eavesdrop on the neighbors.

Re:security (1)

imroy (755) | more than 4 years ago | (#30965324)

How many homes don't have windows?

I may be wrong on this, but I seem to remember our Australian building code requiring a minimum amount of ventilation for any room that will be occupied by people, and the same may apply in other countries. So you have a few options - usually a window or an exhaust fan. People tend to favour windows (note the lower case 'w'). So I'm guessing there aren't many rooms in homes that don't have windows (again, lower case 'w'), for strictly legal reasons.

Naturally (5, Funny)

Junta (36770) | more than 4 years ago | (#30964678)

Light, in a room without windows, will not escape the room, improving security.

As usual, Windows makes networking less secure, why am I not surprised.

Re:Naturally (1)

syockit (1480393) | more than 4 years ago | (#30964752)

I was about to say "I see what you did there" to the submitter. Well, it seems someone else pointed it out in a different manner.

Windows (0)

Anonymous Coward | more than 4 years ago | (#30964688)

> Traditional radio frequency systems (Wi-Fi , WiMAX etc.) do not require line of sight transmission, but can pass through some substances and so present a security problem. Light, in a room without windows, will not escape the room, improving security.

Geeze, there you guys go again, always blaming windows for being so insecure!

Doors are a part of the problem, too, you know!

Good for site-to-site (1)

arndawg (1468629) | more than 4 years ago | (#30964696)

Seams like a good way to connect multiple buildings when you don't have any cabled infrastructure between them.

Windows = A security hazard (3, Funny)

Arancaytar (966377) | more than 4 years ago | (#30964728)

Light, in a room without windows, will not escape the room, improving security."

Well duh, everyone knows that avoiding Windows improves your security.

Re:Windows = A security hazard (1)

Atmchicago (555403) | more than 4 years ago | (#30964940)

I was going to say, preventing outdoor light from entering the room is just another way of getting security through obscurity! We all knew in the back of our minds why working in dark basements was a good idea...

Re:Windows = A security hazard (0)

Anonymous Coward | more than 4 years ago | (#30965084)

explains why linux freaks all live in windows-less home basements of their parents, then?

Blindness (1)

enriquevagu (1026480) | more than 4 years ago | (#30964772)

Erm....

"high-powered laser diode"

Doesn't it cause blindness? Isn't it the reason for fibers to have power sensing mechanisms that detect broken segments, for safety reasons?

Is this valid only for rooms without windows and without people?

HP used to sell a product like this (4, Interesting)

Animats (122034) | more than 4 years ago | (#30964790)

IR office networks were popular around 15 years ago. HP used to have a "NetBeame" IR access point product line. (There's one on eBay for $49. [ebay.com] ) There's Linux support for IRNet. The Infrared Data Association is already promoting gigabit IrDA.

The concept of diffuse IR networking works fine, but it never really caught on. You can usually get a signal with one bounce, typically off the ceiling, but more than one bounce and it tends not to work. You don't get any useful diffraction around obstacles at IR frequencies, so shadows are a problem. If you populate the ceiling with little IR domes, it works fine, and I've seen that done, but it's obsolete technology now.

However, if it's laser based... (1)

Colin Smith (2679) | more than 4 years ago | (#30965126)

You have may be able to modify it for cheap gigabit line of sight. Which isn't an obsolete technology.

 

Re:HP used to sell a product like this (1)

atamido (1020905) | more than 4 years ago | (#30965450)

The opposite of this has actually been used with casinos and hospitals for tracking things in rooms. Employees and/or patients wear IR transmitting badges or wristbands that transmit a burst every so often, which are picked up by receivers in every room. It's a simple method for tracking people's movements over time. It's a good way to find out about employee theft in a casino. Also, for example, they would place wristband transmitters around an infant's wrist. If someone tried to cut off the band (so as to kidnap the infant) it would immediately begin transmitting at max power, alerting the staff.

Of course this was probably 15 years ago that I can confirm it being used, so I don't know that it's still being used. It's not a bad idea either at the transmitters/receivers are easily room specific, so it's probably much simpler than trying to triangulate with signal strength.

now for iPad! (1)

the_fat_kid (1094399) | more than 4 years ago | (#30964800)

I smell a grant proposal
I think that they just strung together hot buzz words, Mad-Libs style
Wireless optical? what could be the problem with that?
I have a cordless monitor that I'd like to tell you about too...

Light cant pass thru walls (1)

nurb432 (527695) | more than 4 years ago | (#30964886)

Which makes its mostly useless for 99% of us, unless you run cables to repeaters everywhere, which sort of defeats the purpose.

And how well would it work outside? Not well i would imagine.

Re:Light cant pass thru walls (3, Funny)

yup2000 (182755) | more than 4 years ago | (#30964998)

since when can't lasers pass through walls!? :) Use a BIGGER lazer!

Self interference (1)

AJWM (19027) | more than 4 years ago | (#30964918)

I don't see how this can work at the speed they're claiming. 1+ Gbps means they're pulsing that light at sub-nanosecond intervals (or else doing something really amazing with frequency shifting, which I doubt). Since light travels less than a foot per nanosecond, if you're just bouncing it off the walls you're going to get echoes delayed by multiple pulse lengths and fractions of pulse lengths. Not a problem if the receiver is just seeing a single point, like in fiber, but how does that work in a room?

Re:Self interference (1)

jhfry (829244) | more than 4 years ago | (#30965016)

Hmm... you don't see how it can work, so it must not work.

Perhaps they are using multiple light frequencies with multiple transmitters and receivers, each capable of only 100MB? Perhaps they simply know more than you do.

I would wager that they are doing something relatively new, or the technology would have existed already... so it's not all that surprising that you don't understand it.

Re:Self interference (1)

pclminion (145572) | more than 4 years ago | (#30965460)

Yeah, we have no fucking idea how to deal with echoes. It's not like we have a cellular network that handles multi-path, selective fading, and moving transmitters... Light is a bit harder to modulate than radio frequency, but it's still just a wave, and we actually do have a few years (somewhere around 100) of experience with modulation schemes.

The idea that you think they are pulsing a little light on and off at 1 GHz made me laugh out loud.

Give thanks to the CSIRO (0)

Anonymous Coward | more than 4 years ago | (#30965554)

Ever wondered what the wifi patent suit by the Australian CSIRO against a bunch of American megacorps covered? It was the algorithms and technology to solve just the problem you've just mentioned (in the RF band). The engineers were Radio Telescope scientists, see the story and transcript at http://www.abc.net.au/catalyst/stories/2708730.htm [abc.net.au]

Re:Self interference (0)

Anonymous Coward | more than 4 years ago | (#30965920)

Original press release by PSU [psu.edu]

One of the researchers, Professor Mohsen Kavehrad [psu.edu] , has also worked on 100Gbps transmissions over 100m long Cat7, for example, so these people are not noobs playing with laser diodes from DVD-drives. The article mentions that "the researchers chose to take a different approach using multi-element transmitters and multi-branch optical receivers in a quasi-diffuse configuration." This article [psu.edu] gives slightly more details: "The challenges regarding attenuation and multipath distortion can be overcome by using multi-spot diffuse configuration and fly-eye reception ( Kavehrad & Yun, 1992 ). In this configuration, the transmitted beam is split in a control manner into several narrower beams by means of holographic beam-splitters. The narrower beams illuminate selected spots on a reflecting surface. Thus, path loss due to diffusion is reduced, and fly-eye receivers can use diversity combining techniques to increase signal-to-noise ratio."

What this means is that each receiver only works with one narrow beam which is unlikely to be affected by different path lengths in the same signal and the signal from multiple receiver pairs is aligned and combined to increase the signal to noise ratio.

To the guy who can't help but laugh at the notion of pulsing a little light on and off at 1GHz: That's exactly what they're doing. The magic is in the receiver.

unlikely to get anywhere (2, Insightful)

v1 (525388) | more than 4 years ago | (#30964944)

users won't tolerate very intermittent connections, and won't tolerate having to aim their system at all. I remember using irda brirefly, and it was very touchy.

Wifi is generally omnidirectional. light doesn't work that way - you can get a very strong signal 20 feet from it, or a nonexistent signal six inches away, if you're in a bad spot. And this effect occurs in both directions, and has different deadzones. So not only are you having a problem receiving, you're also having a differnt problem sending, requiring a great deal more adjustment to get communications going. Having to solve two positional problems simultaneously effectively quadruples the difficulty of the task.

It's also going to be a great deal more environmentally sensitive. You can drop a bar or two if someone sets their laptop bag down beside your laptop and clouds direct line between you and the access point. Imagine how much worse that can get with light, and at a greater distance - you won't just lose a bar or two, you're almost certain to get completely disconnected. A couple chatting as they walk down the hall ten feet from you could ground you for several seconds, giving you absolutely no hint of what caused it.

No, this technology's not going anywhere. Sure it works, but it's nowhere near as reliable as the public will demand. Look how badly people flip out now over an occasional dropped call.

Re:unlikely to get anywhere (1)

TheRaven64 (641858) | more than 4 years ago | (#30965252)

I can see one use for it: ad-hoc networks. You wouldn't use it for a home network, but it would be nice for networking a few laptops together with no infrastructure, so people having a meeting can be on a network and exchange files easily.

Re:unlikely to get anywhere (1)

v1 (525388) | more than 4 years ago | (#30965718)

I can see one use for it: ad-hoc networks.

I would agree with that. If I wanted to send something largeish to someone else where I was it would be useful to set our laptops back to back for example and basically irda a file over. Sort of like a fast bluetooth ad-hoc. In that scenario, physical arrangement etc is already expected to be optimized.

I remember printing to an irda printer a long long time ago. (1999-2000 or so?) That was before 802.11 was around, and people were trying to figure out how I was printing leaning back in my chair with the laptop, no cables attached. And we got to see a little bright green light shining from behind the strange black patch on the front of the printer for the first time. (the irda window, the light came on when irda was in use) But it was slow and unreliable, and irda had two competing standards, it was only by chance that the printer and my laptop supported the same standard. In that instance the printer needed to be within about 30 degrees of facing me, and the same with my laptop's back side to it, and range was only about 3 feet max. The farther you separated, the harder the aim was, and it was largely a trial and error because there was no way to determine signal strength, so it may have had better range if the aim had been closer to ideal. From what I've read here, they're trying to eliminate the aim issue. In reality, the only way to get it to work reliably and consistently was to set the laptop down right in front of the printer, about 5" apart.

The idea of "security" here is almost irrelevant. It's like being concerned about privacy when you're using two tin cans and a string - privacy is the least of your problems.

What happens if... (2, Funny)

magsol (1406749) | more than 4 years ago | (#30964950)

...a friend of mine runs into the room in the middle of a download and starts playing with a flashlight?

Re:What happens if... (1)

MartinSchou (1360093) | more than 4 years ago | (#30965684)

Here's what happens when you read stuff and you're a bit drunk:

What happens if... a friend of mine runs into the room in the middle of a download and starts playing with a fleshlight?

windowless rooms (2, Insightful)

johnrpenner (40054) | more than 4 years ago | (#30965054)

great - so now millions of drones will have to sit in windowless rooms so the network wont leak out... and the air and the trees and the birds cant leak in... dismal existence... borg colony bleah! :-P

I'm curious of the on affect people with seizures (1)

Brigadier (12956) | more than 4 years ago | (#30965108)

I'm wondering what frequency this will oscillate at and if this will potentially effect people proned to seizures ?

Re:I'm curious of the on affect people with seizur (1)

phil reed (626) | more than 4 years ago | (#30965164)

To get up to a gigabit data rate, the pulses will be so fast you'd never see them. Even if it's multiplexed across many "frequencies" (colors), the pulsing will still be far faster than any eye could detect.

Plus, you're assuming it would be visible. Infrared would be somewhat easier and cheaper to generate.

Re:I'm curious of the on affect people with seizur (1)

Dunbal (464142) | more than 4 years ago | (#30965326)

I'm wondering what frequency this will oscillate at and if this will potentially effect people proned to seizures ?

      I don't think they would be so silly as to use a visible part of the spectrum. Rather I expect them to use the same frequencies used by say the remote control for your television. If it's invisible, it won't cause seizures because, well, it's invisible - the brain will not detect it. I have yet to read about television remote control induced seizures. Also if you're transmitting data, the "pulses" will be far too fast for you to notice even if it WAS visible light. Heck you can't even see your regular incandescent bulb turning on and off at 50/60Hz (depending which continent you live on). Now imagine the gigahertz range...

Of course if there are people willing to claim that radio wi-fi causes all sorts of "allergies", I'm sure there will be even more crackpots faking seizures (but somehow never wetting themselves) to prove how terrible THIS technology is. Luddites are everywhere...

Re:I'm curious of the on affect people with seizur (0)

Anonymous Coward | more than 4 years ago | (#30965604)

Heck you can't even see your regular incandescent bulb turning on and off at 50/60Hz (depending which continent you live on).

I think either you mean flourescent, or I wasn't paying attention in grade school.

Re:I'm curious of the on affect people with seizur (1)

Dunbal (464142) | more than 4 years ago | (#30965756)

I think either you mean flourescent, or I wasn't paying attention in grade school.

Alternating current? The current flows one way in the wire, then the other way. At some point the flow has to be zero to get from one direction to another. When there's no current, your light bulb is technically "off" (not really because the filament is still hot and glowing). The FREQUENCY of the alternating current is 60 Hertz in North America. That means that your lightbulb is switching on and off 60 times per second. Of course due to the residual heat in the filament, it would be more fair to say that the incandescent light bulb is "pulsating" at 60Hz between a maximum and minimum brightness. The nature of fluorescent lights makes this "flicker" even more noticeable, since it's not a bit of hot wire providing light but the actual current moving through a gas.

You must now exchange your nerd card for this pink "probationary nerd" card.

gonna let you in on something (1)

Eil (82413) | more than 4 years ago | (#30965306)

I know this is like super-secret insider knowledge in the IT consulting circles, but it's something that I just have to make public no matter what the consequences are.

If you have computers in the same room that need to talk to each other, there's actually a really easy solution that is almost 100% reliable, doesn't require fiddling around with transmitters and sensors, and best of all only costs a cool $2 [google.com] for the whole solution.

Just remember, you didn't hear this from me.

Re:gonna let you in on something (1)

cenc (1310167) | more than 4 years ago | (#30965866)

I was going to post a portable hard drive, but hey if people want to do it the hard way.

Security via opacity? (1)

VortexCortex (1117377) | more than 4 years ago | (#30965394)

Traditional radio frequency systems (Wi-Fi , WiMAX etc.) do not require line of sight transmission, but can pass through some substances and so present a security problem. Light, in a room without windows, will not escape the room, improving security."

As if security through obscurity weren't bad enough, now we'll have security via opacity... which can easily be defeated by slipping a fiber optic cable under the door, or through a small hole in the wall.

Bottom line: You'll still need to encrypt your data and it won't be any more secure than Wi-Fi. Both Wi-Fi and Optical signals will only be as secure as the encryption system they use.

So, Optical transmission IS NOT more secure than Wi-Fi, and it sucks at traveling through walls (unlike Wi-Fi)... Wired 1Gps networks don't "leak" from the room with the door and windows open either... ( why we should care about this? )

Has anyone thought about upoads? (1)

SwimmerBoy (1612523) | more than 4 years ago | (#30965400)

What if I want to upload a file, or even just send the small amount of data to request a download? Will my laptop suddenly turn into something resembling a 90's rave?

a room without Windows (1)

frovingslosh (582462) | more than 4 years ago | (#30965548)

Light, in a room without windows, will not escape the room, improving security.

That would be great, if that was what wifi was used for. But it is not. If the connection was limited to a single room, ethernet cables could be used, which would give even better security. Far more wifi systems are set up to get the network connection between rooms, even between floors of a house, than for networks in windowless rooms.

Besides, everyone already knows that a computer room without Windows is more secure than one with Windows.

Color me skeptical (1)

Peter Simpson (112887) | more than 4 years ago | (#30965602)

At a former job, I worked with a bunch of guys who had tried to develop a free-space optical Token Ring network. Aside from the inadvisability of basin it on the Devil's own networking protocol, their biggest problems were multipath and low receiver signal level.

They never got it truly working. I suspect these guys won't either. Signals bouncing off walls attenuate pretty quickly with each bounce and you end up needing a fairly large surface area detector.

I'm surprised (1)

elsJake (1129889) | more than 4 years ago | (#30965846)

Nobody knows of Ronja [twibright.com] . It's been around since forever.
Visible laser based point-to-point networking good for 1.4km@10Mbps. I think they were working on a 100Mbps version as well but i haven't seen much progress in that direction.
Sure it's not 1Gbps and it doesn't serve the exact same market segment but the technology is already here , it's cheap to build and the designs are free so i thought some of you might get some use out of it.

Sounds like a great idea... (0)

Anonymous Coward | more than 4 years ago | (#30965910)

...for Raves or Dance parties, but less so for those with epilepsy.

This could put a crimp in war-driving (1)

Pictish Prince (988570) | more than 4 years ago | (#30965960)

That being said, there are a hell of a lot more uses for a LAN than internet access. Can you imagine a LAN party at 1Gbps?
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