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'Corkscrew' Light Could Turbocharge Internet
ananyo writes "Twisty beams of light could boost the traffic-carrying capacity of the Internet, effectively adding new levels to the information superhighway, suggests new research. In the last few years, different groups of researchers have tried to encode information in the shape of light beams to ease congestion, using a property of light called orbital angular momentum. Currently, a straight beam of light is used to transmit Internet signals, but certain filters can twist it so that it corkscrews around with varying degrees of curliness as it travels. Previous experiments using this effect have found that differently shaped light beams tend to jumble together after less than a meter. Now, a team of researchers from Boston University in Massachusetts and the University of Southern California in Los Angeles has found a way to keep the different light beam shapes separated for a record 1.1 kilometers. The most imminent use of the cables, the authors say, might be to install them to span the short distances between servers on giant 'server farms', used by large Web companies such as Facebook."
I saw a piece on this back in the early 90s on Daily Planet - I could never find it again and no one else seemed to remember it. Glad to know I'm not crazy!
It's definitely a cool idea, but sheesh, this is Slashdot, people! We don't need a kindergartner's description of how the Internet and fiber optics work.
It's 2013, does that make the term "Information Superhighway" retro?
I'm god, but it's a bit of a drag really...
If this needs new cables then maybe in the data center but installing them all over place will cost a lot + all the hardware that will need to be updated.
People are probably beter off reading the wiki...
Key bit of information...
OAM multiplexing can not be implemented in the existing long-haul optical fiber systems, since these systems are based on single-mode fibers, which inherently do not support OAM states of light. Instead, few-mode or multi-mode fibers need to be used. Additional problem for OAM multiplexing implementation is caused by the mode coupling that is present in the fiber, making direct-detection OAM multiplexing still not being realized in long-haul communications. In some specialty fibers, OAM states were transmitted with 97% purity after 20 meters.
Basically this demonstration technique uses specially designed fibers that can carry the "donut" TEM mode required for OAM which is the reason they made a comment that the most likely for fibers the implement this technique "might be to install them to span the short distances between servers on giant 'server farms'"...
Since this was created at a University it is unclear on which company will attempt to patent it first. Any bets? Should be start a pool?
It's the "worst description of polarization ever" because it's apparently not polarization:
The orbital angular momentum of light (OAM) is the component of angular momentum of a light beam that is dependent on the field spatial distribution, and not on the polarization.
You do not have a moral or legal right to do absolutely anything you want.
More twisted porn!
Have gnu, will travel.
Bandwidth is a ratio of data size to speed. (Data Size / Time) If data size increases by a lot, but the speed slows down a little, it is a net bandwidth is increased.
The example of having a truck loaded up with hard drives driving down the highway has a larger bandwidth than many other options.
Yes, color is used. But not the way you think it is.
Chromatic dispersion causes different wavelengths (colors) to propagate at different speeds. So what would start out as a coincident red and blue bit wouldn't stay that way very long. But using separate colors as one would use separate fibers with each carrying its own data stream does work.
then the color would be purple.
Your eyes and brain work that way. Other sensors don't. A 'red bit' plus a 'blue bit' will not trigger a purple sensor.
Have gnu, will travel.
If they ever got the distance extended, I could see this being handy for long-haul links (although is it really better than a CWDM or DWDM?) But over intra-rack links, it'd have to have a pretty small premium over current technologies to be able to justify using it over just laying another strand of fiber.
In all but HPC applications bandwidth is rarely an issue anyway. You might occasionally use those for trunk lines, but again, why not just lay another strand?
Do they realize how much fiber is lit at gigabit and below? 10ge is hitting mainstream and 40 and 100 following on quickly. CWDM is dirt cheap and DWDM is getting there as well. Replacing all the long haul fiber is a non starter could be useful in 100ge short reach dropping it from 10 or 4 lanes to 2.
One the physical side 25gbps looks to be the plateau we are hitting 16 lanes gets 400ge ports.
No sir I dont like it.
Curve the bullet.
Silence is a state of mime.
How corkscrewing light will turbocharge anything...
Will the exhaust light impact an impeller that then compresses the light on the other side?
Because (I direct this to every idiot who mis-uses the term "turbocharge") THAT is what a TURBOCHARGER is.
A compressor that is powered by exhaust gas.
If whatever damn device you are speeding up does not contain: /end of rant
an waste exhaust-driven impeller
an impeller driven compressor
then it is NOT turbocharging.
From the article:
The work published today used clockwise and anticlockwise versions of twisted light with a specific curliness, but Ramachandran says that the team has since done other research that suggests that about ten different beam shapes can be used to convey information.
That is exciting because each shape could potentially act as an entirely new level of traffic on the information superhighway. On each level, streams of data could be further divided into narrow lanes of colour, maximizing flow. "We showed a new degree of freedom in which we could transmit information," says Ramachandran.
It sounds like you are getting ten times the information. Even if latency doubled, it might be worth the tradeoff with applications such as file transfer and music/video streaming.
What you're describing would be WDM, and this is OAM or Spatial Multiplexing depending on who you talk to.
Your eyes and brain work that way. Other sensors don't. A 'red bit' plus a 'blue bit' will not trigger a purple sensor.
That's not really true, photodiodes and avalanche photodiodes are not channel specific. I can connect a transmit from a 1560.61 to a RX of a 1558.98 and they will work just fine. Most are wide-band and will happily receive anything from 1250 to 1650 nanometers.
If I mix those wavelengths with a combiner and send them into a receiver, I'll get a loss of frame because the signals conflict. The channels have to be 'demulitplexed' at the far end with some kind of WSS, AWG, FBG or other optical device.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
It seems at least plausible that this could be used in conjunction with some form of WDM to get higher densities than either alone.
Works great as long as all your cables are perfectly straight. If you want to bend the cable, you need to plug it into an angled repeater.
The repeater, of course, requires an external power source.
It does sound like right or left hand circular polarisation to me too.
The truth shall set you free!
they have similar marketing spew already for their overpriced fiber optics:
http://www.monstercable.com/productdisplay.asp?pin=3792
Dude every time I think porn can't get more twisted i'll have a customer come in with a new porn bug and will completely break the scale again, so I'd say porn getting more twisted has got to be one of the laws of the universe.
ACs don't waste your time replying, your posts are never seen by me.
This sounds like what these guys were doing: http://hardware.slashdot.org/story/12/06/25/1215246/twisted-oam-beams-carry-25-terabits-per-second
Not sure if its the same groups or not, but pretty much the same idea.
I think of it as being analogous to injecting separate beams of light at different angles, having them bounce back-and-forth between the walls at different distances between bounces, and emerge at angles corresponding to the angles at which they entered.
Of course it's not angle of flight that's in question, but another property of the light propagation that can be varied to allow different beams to propagate down the fiber and be separable at the far end. But they're still separate because each beam's cross section at a given plane cutting the fiber has a different distribution of phase and intensity, resulting in different propagation mechanisms that conserve a property which can be used to separate the beams when they emerge.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
This is just a dumb idea and a waste of investors' money. The technology already exists to put many colors on the same fiber and unlike optical modes (which is what they're really talking about) colors don't change over distance or bleed into one another.
What it means is that they're using other than the TEM mode of multimode fiber. It can be done but it has problems with dispersion and decoherence with distance. Every optical and probably ever electromagnetics engineer learned about this in school and most of us concluded that single-mode fiber was preferable because it doesn't have those issues.
The standard method for multiplexing signals on fiber is therefore to put it on different colors instead of into different excitation modes. That way they can be used over very long distances and there's zero bleed-over from one channel to another.
More or less. More detail here: http://stanwir.seecs.nust.edu.pk/Lectures/FOCS/Modes%20in%20Optical%20Fibers.pdf