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Science

Chaos Theory Applied To Netwok Data Transmission 84

Posted by CmdrTaco from the faster-ways-to-download-porn dept.
Gentry writes "Researchers tout 125 MB throughput by applying chaos theory to fiberoptic data transmission. Certainly still a conceptual technology, but the article outlines some interesting potential. "
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Chaos Theory Applied To Netwok Data Transmission More

Chaos Theory Applied To Netwok Data Transmission

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  • I don't know about you, but I don't want Joe Random Luser using my wok! It's not open source, damnit!
  • Perhaps gram-bits refer to a tasty new gramcraker snack from those little elves at kebler

    mmmmmmmmmm gram-licious

  • OK? (Score:1)

    by alany ( 1398 )
    Does this just sound like conventional data spreading to anyone else? Seems like they are scrambling the data stream with a pseudo-random sequence. What is new about that, lots of modem protocols use it?

    I gather they have some other protocol development to improve the data throughput?

    More info please, that article is lacking any real information.
  • Depends upon how non-linear the lasing system is. At low amplitudes near the lasing threshold any laser will act randomly as far as spatial and temporal coherance goes.

    Intresting field of study actually, you can see quantum effects in the macroscopic output of the laser. Although it could be argued that a sparking fluro light or dripping tap demonstrates exactly the same thing.
  • I have a degree?

    Well I am a Electrical Engineering student, and a Computer Science student, but I have not graduated yet.

    If you are looking at the vk2zay, that is my HAM call. I know a fair bit about lasers, I experiment with them a bit at home.

    It was just a comment, jeeze... Sounds like envy.

  • It sucks that people don't know their base units. What sucks even more is that the media makes it almost impossible. I've seen "mega-bits" written as "mb, MB, Mb" and "mega-bytes" written as "mb, MB and Mb".

    From the metric system:

    • M = mega (in computers, 1024*1024)
    • G = giga (in computers, 1024*1024*1024)
    • T = tera (in computers, 1024*1024*1024*1024)
    • k = kilo (in computers, 1024)
    • K = kelvins (unit of temperature)
    • m = milli
    • g = gram
    • B = bytes, b = bits (computer units)
    This makes for some useful and rather silly units of measure, depending on the letters you use and their case:
    • kB = Kilobyte (correct!)
    • MB = Megabyte
    • mB = Millibyte (not a real measurement)
    • Mb = Megabit (correct, not to be confused with MB)
    • mb = Millibit (not a real measurement)
    • KB = Kelvin-Byte (not a real measurement.. temperature/data-rate??)
    • gb = Gram-Bits (not a real measurement.. mass/data rate??)
    So the next time someone says, "I have a 50K file for you," your next exclamation needs to be, "Wow, that's cold!"
  • Am I missing something? Else what's the big deal of 128Mbs? If it was 128Gbs, then that would be cool... though I thought the world record, in the lab, for a single bit of fibre was well over 1Tbit/s.

    Or does he mean he's improved the efficiency? 100Mb ethernet runs at 200Mhz - it uses 2state changes to indicate 1 bit for reasons of reliability. (can't remember the technical term for this...)

  • I think these guys are bluffing. How the Hell do you get chaotic information from a laser, one of the finest examples of coherence and organization in the physical world? Their off-the-wall speculation about using neurons in computers, and their wild extrapolation to the possibility of talking to your computer in natural language, shows the sloppiness of their thinking and the cavalier flashiness of their press presentation.

    (For what it's worth, I know what I'm talking about. I have a degree in cognitive science, and I'm going on in grad school in complex systems.)

  • Sorry, but the engineer in me hates to see science being confused with engineering solutions.

    OLD-ethernet: Manchester encoding (one transition per bit) 1-2 bit encoding
    NEW-"ethernet"-(100baseT,etc): 4-5 bit encoding

    The number of transitions you need to encode per bit only has to do with clock recovery and jitter.

    With the ME2:1 scheme there is a clock with every bit. With the 4-5 scheme the 5 bit symbols are
    chosen to have the fewest concecutive same symbols. So you may not have a clock with each
    bit, but you interpolate time to get the clock you need. More sensitive to jitter, but higher bit
    density.

    You can take this ad-infinitum and get RLL (run-length-limited). You can even just guess the
    patterns before they stabilize like PRML (partial response, maximum likelyhood). This has all been
    done with the hard disk in your computer.

    Although this kind of stuff started out as science, it is so old, that now it is considered
    applied science or engineering.

    If chaos modulation is really new science, it should rely on new scientific principles that
    are different from stuff that's been working for the last 10 years. This article is unclear on
    this point.
  • old news. by compiling mod_chaos into apache 1.3.x, I have been able to access the Hubble telescope command set (via secure port IRDA access) and snap some wonderful shots of the microsoft executive female restroom.
  • Is it me, or was the article full of errors? Fractals, from what I recall, are NOT the same as chaos theory. There are relations there, such as the iterative nature of both, but there is a distinct difference. Second, what does this have to do with machines having a conscious? Just because neurons are used for computation, does not mean the machine is instantly self-aware.

    Usually I don't whine, but they're just spreading fear. "Oooooo, it's using biological components, watch out!!" And then the public starts getting pissed, and research dries up.
  • That's good, i like that. I had just thought it was a bit of chaos right there in the headline to get the point through.

  • The sad thing is most of the people who populate slashdot are too new to the net (i.e. "ARPAnet? whazzat...more OSS dude") to understand the pun :(

  • Think of how this works as a big quantum one-time pad cryptosystem. You can actually transmit the message at FTL speeds, but you cannot decrypt the message until you get a copy of the key pad. The key pad is restricted to travelling no faster than the speed of light. The end result is that the data does move FTL but you can't decode it until the key arrives. [No this is not quite how it works, but is a good enough explanation on why this little trick will never provide the FTL communication system everyone thinks it should be able to provide.]
  • I don't understand this stuff at all, so I'll keep it short. SETI's search for extraterrestrial signals has been disappointing thus far. Could they be searching for the wrong type of signal?

    How, if possible, would one detect distant communications signals based on an advanced form of the chaotic system described in the article?

    -kent
  • But did you know that Giga is pronounced "jiga"?
    (from same root as gigantic)
  • Do lasers work backwards as photo-detectors the way light-emitting diodes are supposed to do?
    Or is it a lasar (light amplification by stimulated absorption of radiation)?
  • "Ditto says the only requirements for building a chaotic operating system are two irregular or unpredictable elements."

    A human user and a computer

    "Ditto says the only requirements for building a chaotic operating system are two irregular or unpredictable elements."

    Microsoft's secret formula!
  • What makes it even more difficult is that even those units you list above are used in different ways depending on what technology they are used to measure:

    Mb = Megabit, but this can mean either 1,048,576 bits (2^20) or 1,000,000 (10^6). How fsck'ing annoying! In networking 1 Mb *usually* means 10^6, but for memory it means 2^20.

    It seems like most hard drive companies now list their drives where 1MB (Megabyte) equals 1,000,000 bytes! Those sneaky bastards!! Anyone know when they started doing this? I swear I recall having some old Seagate drives on which 1MB equaled 1,048,576 bytes...

    -beb

  • shrimp.... plate of shrimp
    It's the Cosmic Unconsciousness
    find one in every car You'll see
  • Since I never use usenet, I can't be who you think. In fact, I'm so inept at computer wienner stuff that I have trouble with the slashdot login and must often post as anon. coward.

    I am, however, familiar with chaos theory and have published a several papers on it's application to real problems. I'm a big fan of Prof. Roy's (& Ditto), the INLS at UCSD, Lou Pecora at NRL, and Harry Swinney at UT. I've seen alot of dumb stuff on chaos go by (Yuri Kratsov for one), but the Ga. Tech research is real, useful, and will come to fruition.
  • I have an excuse for cruising slashdot, I'm a classically trained engineer. But, what's a real physicist of repute doing on a propellor head site like slashdot? Since you've departed your Eiffel phase, I thought you might be cured.

    So, if these computer wiennies are such experts, how come not one of them was in sunny, warm, dry LaJolla earlier this week? Always a pleasure to hear Lou. But, that cryto guy -- is the hostile she a diffeomorphism? That is, is he implying all hostiles are shes or that all shes are hostiles. It wasn't clear.
  • At high power levels lasers are not coherent. In fact, the failure mode is a classic descent into chaos.

    Were you a student of mine, you'd flunk. For all the research you did to check this out, have you considered a career in hamburger flipping?
  • Despite the ignorant tone of most of the comments here in dorkland, there is important research being done on the application of chaos theory to real problems:

    Institute for Nonlinear Science (UCSD)
    http://www.zweb.com/apnonlin/

    NRL
    http://code6343.nrl.navy.mil/
    http://chaos-mac.nrl.navy.mil/

    and the Ga. Tech sites
    http://www.physics.gatech.edu/
    http://www.physics.gatech.edu/chaos/
  • Rajarshi Roy, professor of physics at Georgia Tech, reports that he has sent data at 125 megabits per second - more than double what's possible with binary protocols - by using what he has labeled "chaos communications.


    Ok, whell thats good and all, but maby he has never herd of OC-3(155Mbs) or OC-12(622Mbs) witch are some of the most common forms for the internet back bone. Also what about 1000Base-BX and the soon to come 1000Base-Tx witch should work over standard Cat5 twisted pair.


    while chaos computing sounds good to me, i think it has more to do with the Hardware and OS, then protocals are second nature :)
  • In theory it's pretty simple...if you had a system with two strange attractors you could generate a sequence of eight bits just by plugging the right constant in the right place. Each time it goes around strange attractor A, that's a zero; each time it goes around strange attractor B, that's a one. Lorenz's equasions for modeling the weather could do it pretty simply.

    You could double your output with a more complicated five-variable system with four strange attractors; but it's not very far scalable after that.

    The geek who thought up this scheme is Rajarshi Roy [gatech.edu], chair of Physics at the Georgia Institute of Technology [gatech.edu]. You'll be seeing more chaotic computing coming out in the near future.
  • What do you think Benoit Mandelbrot was working on when he *named* fractals? That's right...network transmission failures. ::sigh::

    _Deirdre
  • Is it related to Ewoks?
  • I thought the bit at the end about the other guy planning to use live neurons in a computer was neat, it could lead to some great tech support calls...
    CALLER: My computer won't let me change my password, and it keeps asking where the dog went - we don't have a dog! What's wrong?
    ANSWER: I'm sorry sir, your computer has Alzheimer's.
    Opens up a whole new field of computer psychology, professional PC therapists making sure you've got a well-adjusted machine. :)
  • Probably they have a butterfly router :)

  • There's a press release from GA Tech with more info here [gatech.edu] and on this page [gatech.edu] there's a paper (PDF or PS) on it.

    Go, wramblin' wreck...
  • 25Mbps over a fiber isn't such a big deal

    No, it's not.

    The maximum speed using electronic technology is OC192 (2.48Gbps), after that you must switch to purely optical technology

    This is purely optical technology. The article at GA Tech says there's no theoretical limit to the bandwidth, so who knows? Maybe it could be used for > OC192.
  • I've taken a look at the article, and this just appears to be a fancy way of modulating data on to the laser beam carrier. The fundamental limits remain the same as with other methods of transmission. That they see a bandwidth increase is not a surprise, because they are using an analog waveform to carry the data instead of a digital pulse train. The down side to this is greater suceptiblity to noise.


    The fundamental maximum bandwidth of a fiber optic line using visible light at sane power levels is on the order of 10^14-10^15 bits per second, roughly corresponding to the frequency of oscillation of a light wave at visible wavelengths. By using analog data encoding you might be able to bump this up to 10^16 or higher, but you'd pay dearly for it in terms of power consumption (as your beam needs to be brighter if you want to have more intensity levels available). You can similarly improve noise rejection by using a brighter beam.


    For those of you with time on your hands, the maximum sampling rate that you can meaningfully use is the frequency of the photons being transmitted (C / wavelength), the error in the measurement of the number of photons received is roughly the square root of the number of photons, and the energy of a photon is proportional to its frequency, and is single-digit eV for visible light.


    And I seem to recall hearing about terabit fiber being demonstrated a while back.

  • A bit is a binary digit, 0 or 1. A byte is (usually) a collection of 8 bits, representing an integer from 0..255 (unsigned) or -128..127 (signed). As it takes 8 bits to store one byte, there is a substantial difference in capacity between bits-per-second and bytes-per-second.


    And as Ur_vile pointed out, some machines use bytes that are not 8 bits in length. However, you aren't likely to encounter them outside of computer research labs [note the "likely" before flaming me, please].

  • if you actually READ the article, it clearly says "he has sent data at 125 megabits per second." this is not really too fast compared with what was actually posted (less by a factor of 8).


  • So you said what? 125MB * 8 = 1GB?? Your point?

    The whole article is full of BS. It's a clear case of a geek grad-student with no life except for his research, talking to an air-head CNN reporter who has about as much common sense as fractals have in common with chaos theory.

    A 125MB datarate is a 1Gbit datarate. Gigabit Ethernet has been on fiber for some time now. Firewire is promising to bump it from the top-dog spot. A 1Gb datarate in fiber is nothing new.

    On another note, they may be applying chaos theory to soliton handling - but it doesn't say anything like that in the article.

    Reread the first paragraph folks, it'll tell you exactly how it got into CNN.
  • Could they be searching for the wrong signal? Sure, or they could be looking in the wrong place, which is more likely.

    Sagan postulated in Contact, that the signal would be so un-natural as to not be missed. A sequence of prime numbers fits the bill. Now, I recall something about the frequency being related to the natural frequency of hydrogen, and I don't quite understand that. There's plenty of hydrogen out there, all lit up and transmitting - so why blend in?

    I'd say that if the signal pattern is to be unique, so should the frequency/wavelength. Maybe we're just not able to detect un-natural frequencies yet? Or, maybe they just don't want to talk to us. :) Why would they want to talk to someone who can't listen to their (pi/e)GHz signal?
  • State you background and experience. Just because you have a degree doesn't mean you know anything.

    Why not ignore both degree and background/experience,
    and look at the content of the message instead?

    On /. I treat all messages the same way -- I doubt them ;)

  • Automagically? What a great term!

    Yeah, isn't it! But hardly a new one. It's been in everyday use, at least at my University, for many years now. I suspect it's not long until it makes it as a dictionary entry:

    Automagic When something occurs
    automatically, as if by magic.

    :-)


  • In recent news today industry leaders were baffled when they realized that the engineers at microsoft were actually developing something. They were developing the most chaotic OS known to man. One MS employee was quoted as saying "Yes, WINDOWS 2K (TM) will be based on such advanced chaos theory that trying to comprehend it will render you insane. So, my advice would be to just sit back and let it do what it does. This is based on years of advanced research, we have found that often people would rather not be working, or maybe they are losing -40 to 50 at quake, so in theory the machine would lock up or 'blue screen' at this point. With the chaotic fators involved, Windows 2K (TM) will be able to calculate just when to crash so as to make your life easier!"
  • If anyone reads this, I'll be happy =)
    Anyway, from what I can find and read about the subject, commincations won't be faster because its chaotic; it will be faster because it's optic however. The value is that 1, data won't be encoded digitally, pulses, frequencies, or what not, so more data can be sent on the same signal; Phone lines for example are not digital, but analogue, and in that sense 'more' data is sent over them than can be done digitally; Think how much bandwidth it would take to send voice over a 33.6 phone line, since that is done in analogue, but nigh impossible in digital, without significant ammounts of compression and such.

    Anyway, point 2, since chaotic communication isn't faster, its potentially more reliable and more secure. Anyone familiar with PGP? That may be a good example; if the two lasers could be kept in sync, or in a similar state, it then would be like continually applying a PGP encryption on the data stream; that and the fact that the PGP private and public keys change continuously because the lasers are chaotic, and not static, and are synced as well, so not only are they secure, but unpredictable. Another benefit is that applying a chaotic encryption automatically allows for the analogue transmission I mentioned earlier, so in that sense a chaotic transmission is faster.

    For those arguments for noise and such, redundant and corrective data can always be sent across the wire, right? I mean, network packets are lost and retransmitted all the time now, on the internet!
    -Twink

  • Netwok (Score:1)

    by zod ( 95213 )
    Oh man, that cracked me up.
    I guess I shouldn't read /. at 3am

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