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Supercomputer To Use Optical Router 174

Izmunuti writes "From a NYTimes article: 'Highlighting a radical departure in the design of the fastest computers, the California Institute for Telecommunications and Information Technology plans to announce on Monday that it will use an optical router designed by a Texas company as the heart of a campus-wide supercomputer that will be woven together with optical fibers.'"
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Supercomputer To Use Optical Router

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  • *Yawn* (Score:2, Interesting)

    So how is this any different from using gigabit fiber instead of copper? Although for most large clusters gigabit is too slow when you need to move around a terabyte of data. Look into NUMA.

    • NUMA? (Score:1, Funny)

      by skunky-boy ( 453764 )
      Good God, is there anything that Dirk Pitt can't do?

      NUMA [numa.net] must be -really- branching out. ;)
    • Re:*Yawn* (Score:5, Informative)

      by Alien Being ( 18488 ) on Monday November 18, 2002 @08:43PM (#4702978)
      The innovation has nothing to do with the external connections.

      The interesting thing about this switch is that, internally, it routes photons instead of electrons.

      Once it sets up a connection, e.g. port-5 to port 17, the photons can "just go". In other words, there are no capacitors(wires) and gates(transistors) to slow things down.

    • mabye because it is using an optical router and grid technology.
  • Shocking. (Score:4, Informative)

    by Forge ( 2456 ) <kevinforge AT gmail DOT com> on Monday November 18, 2002 @08:16PM (#4702835) Homepage Journal
    Someone figured out that you can pack more bandwidth and less latency into fiberoptics than copper?

    More importantly they are actualy using an optical router to prevent what has become a botleneck in resent years. I.e. Data comming off a fiber pipe is converted to electrical signals before being routed to it's next destination where it's converted back to little bity laser beams.

    This should be faster than your typical loadsharing super computer (SETI@home) but slower than the miranet using hardcore. With enogh nodes however there is no telling howfast this baby can get.
    • Re:Shocking. (Score:3, Insightful)

      by rtaylor ( 70602 )
      Well... thats half true. Certainly more bandwidth, but not normally lower latency.

      Light through vacuum is quick, light through glass isn't as quick. Couple this with the inability for the light to travel in a straight line through the fibre (it bounces around off the sides -- more or less). Electrical signals through copper don't experience these affects as much.

      Lastly, a rather complex and heavily delayed circuit has to convert the electrical signals to light, and back again. This takes time -- but the percentage of time taken is small in comparison to normal travelling distances but don't expect them to make a slowed down PCI bus using fibre any time soon.
  • by g4dget ( 579145 ) on Monday November 18, 2002 @08:17PM (#4702837)
    "We're moving to an optical-centric world in which the computers are the slow things and you reluctantly add them in," Dr. Smarr said.

    When it comes down to it, the computers do the work. You can do useful supercomputing with almost no networking, you can't do useful supercomputing with blindingly fast networks and no computers.

    (Somehow, the quote reminds me of people who think that managers and lawyers are the important part of a company, and engineers and customer service are a nuisance to be minimized.)

  • Way of the future (Score:5, Insightful)

    by andyring ( 100627 ) on Monday November 18, 2002 @08:17PM (#4702838) Homepage
    Well, we all saw this coming, if you really think about it. I recall hearing talk of a pure optical network switch a couple years ago, that functioned as a switch without needing to convert fiber back to copper. I think HP made it, I could be wrong.

    Anyway, we're about pushing the limits of copper, with 1000bT, and I'd imagine network speeds will only continue to climb with increased use of fiber. I can see, in 5 to 10 years, optical switches becoming more common in office environments as file sizes and network speeds continue increasing.

    • Alas fiber needs to get a good deal more robust if that progression isn't to turn LANs into reliability nightmares. Cat 5 generally works even when you're using too short a length, scrunching it up, tieing knots it it etc. It usually doesn't complain when you do whatever it takes to fit it around someone's desk*. Try that with fiber, and you'll rapidly burn through your sense of humor.

      * Yes, I know Cat 5 can be a right pain in the arse, but it's a lot more robust than (current) fiber.
      • It usually doesn't complain when you do whatever it takes to fit it around someone's desk*. Try that with fiber, and you'll rapidly burn through your sense of humor.

        Obviously you've never worked with fiber. Yes, the big fat cables that go underground are very rugged, and can only be bent to about a 2' radius because of all the reinforcement inside. However, the thin rubber patch cords that you use indoors are very flexible - you could coil it tightly around your finger without damaging the glass inside. The bare glass is even more flexible - you can bend it down to about a .25" radius without damaging it. Fiber is not as fragile as you think, and the pre-cut patch cords are really quite easy to work with.
        • Most modern fiber does not like to be wrapped in a radius less than 1', as it begins to mess with the refractive index of the cable... You get a noticable loss of power as you wrap it more and more tightly. This is really the reason why you can't wrap cables tightly - durability has very little to do with it...
          • Re:Way of the future (Score:2, Informative)

            by Hal-9001 ( 43188 )
            To first order, bending fiber does not affect the refractive index. The main problem with bending fiber is that you lose confinement because, from a ray perspective, the light comes in at too steep an angle and you no longer get total internal reflection and you start experiencing significant signal loss. If you go into more detail, bending fiber probably does cause stress-induced birefringence, which does change the refractive index, but this effect is probably small compared with the significant attenuation due to simple geometrical optics considerations.
    • Yes, but the thing to realize about optical switches is that the switching time is on the order of tens of *milliseconds* (as opposed to nanoseconds), because you have to physically move a mirror in order to change the path. It's totally different from an electronic switch in that you're not switching on a packet-by-packet basis.

      There are several killer apps for this kind of technology: one is setting up dedicated channels between a server and a client, EG so that you can download a 2GB movie in a couple of seconds. Another is dynamic allocation of channels on the backbone - eg if an ISP gets slashdotted, additional fiber channels could be brought up to the backbone provider or other peers. Finally, you can use it to switch a particular circuit over to an alternate route when a backhoe cuts the fiber, without having to have all the fiber terminated at routers on each end - just move the physical link in between.
      • Re:Way of the future (Score:4, Informative)

        by Izmunuti ( 461052 ) on Monday November 18, 2002 @10:52PM (#4703531)
        "...optical switches is that the switching time is on the order of tens of *milliseconds*..."

        Apparently, this company's optical switch doesn't take tens of milliseconds. They claim it can switch in tens of nanoseconds. They call it an "optical phased array" -- no moving parts. They talk about it a bit on their web site.
    • I'd imagine network speeds will only continue to climb with increased use of fiber.

      In other news, computers are expected to continue to be purchased by corporations. Also, breaking news just announced, the obvious will happen and be modded as Insightful.
  • From the article: "We're moving to an optical-centric world in which the computers are the slow things and you reluctantly add them in," Dr. Smarr said.

    Umm yeah... If you didn't add in the computers what good would the optical network be?

    I think this is a great example of what the old saying "think before you speak" is meant to help one avoid.
  • Do we need to sign up for these accounts, or is there a free way in?

    Do they track IP's so could we make a universal slashdot login?
    • As opposed to them not tracking IPs so we couldn't make a universal Slashdot logon?
    • you know what i meant...
    • There is now (Score:4, Informative)

      by coryboehne ( 244614 ) on Monday November 18, 2002 @08:56PM (#4703042)
      A new account has been created for the benefit of slashdot users who don't care to register with NYTimes.

      Username : SDUser
      Password : slashdot

      enjoy everybody

      click here [nytimes.com] to login.
      • A new account has been created for the benefit of slashdot users who don't care to register with NYTimes.

        what the hell is your problem? they're not asking for money. they give us a high traffic, quality content site and all they ask for in return is a free registration! or is that still too much to ask? running a site, especially a high traffic site, isn't free you know...

  • by Lord Bitman ( 95493 ) on Monday November 18, 2002 @08:20PM (#4702861)
    A pure optical router using analog signals which are passed through a crystal and output at certain locations based purely on their wavelength(wich coresponds to the exact binary data of the full packet) and the path which the light beam is forced to take! HA! Ha HA! MWUAHAHAHAHAHAHAA!
    >:D

    What? It could happen...
    • by mindstrm ( 20013 )
      Actually, what we need is a large broadcast multimode fiber network with tunable transmitters and receivers, no switching involved.

      As a paper I once read.. I think it was called "The Fibersphere".

      Switching is simply a hack to get around a lack of bandwidth.

      The concept is that if we have this large, broadcast fiber network, and tunable receivers sensitive enough, everyone could transmit and receive on the same thing, and talk to anyone else. Tuning in to the right signal is all that would be required... just like RF in the atmosphere.. but with much, much higher bandwidth.

      Problem? WE don't have tunable laser emitters yet.

      • by Hal-9001 ( 43188 )
        Actually, there are lots of tunable lasers, and the diode lasers used in communications are intrisically tunable because the refractive index of the semiconductors used to make diode lasers depends on temperature. Thus to tune the emission wavelength over the laser diode's range, you only have to make it run a little hotter or a little cooler.

        I think the bigger problem it that it's difficult and expensive to build electronics to demodulate extremely high frequency signals, so you'd only rather have a few of those expensive boxes feed a bunch of cheap boxes instead of having to give everyone the expensive box.
    • with a wavelength dependant no linearity in the medium would do exactly that.

      An FP inferometer consits of a pait of parallel mirrors, one half silver, the other full. The beam of light enters at an angle, and then the position of the output from the half silvered mirror is wavelength dependant. They are used in situations similar to a diffraction grating, but they can be made much more accuratly. (There are other criteria too, which I forget.)

      This seperates very close fequencies. Imagine - instead of giving a machine an IP, give it a frequency.

      Haveing a laser that is tunable in frequency is not too difficult - the simplest solution would be to use an Optical parametric oscilator. These split the laser into two different colours, and you just block the colour you don't want.

      • Nevermind then..
        Let's just set up a bunch of those dealies in a giant array which has all the functions of the world's fastest punchcard-based computer!
  • by Anonymous Coward
    Optical Router Uses Supercomputer
  • by Embedded Geek ( 532893 ) on Monday November 18, 2002 @08:22PM (#4702872) Homepage
    CL-ITIT [calit2.net] is not related to the California Institue of Technology - or at least not directly. Per their vision statement [calit2.net], they were created in 2000 at UC San Diego and UC Irvine to "help ensure that California maintain(s) its leadership in the rapidly changing telecommunications and information technology marketplace."

    Also, their statement on the Chiaro Networks "OptIPuter" is here [calit2.net]. Caltech is an entirely different animal.

  • by Servo ( 9177 ) <dstringf AT tutanota DOT com> on Monday November 18, 2002 @08:22PM (#4702874) Journal
    Just as the article started to pique my interests, it was over. That sucks!

    Yet another technology article written without any real information. I realize in writing you are supposed to write to the common reader, but sometimes it seems like they would be better off not writing about it at all if they didn't intend on clueing us in on any of the facts.
  • by ender81b ( 520454 ) <wdinger@g m a i l . com> on Monday November 18, 2002 @08:22PM (#4702875) Homepage Journal
    The optiputer will initially consist of about 500 processors linked via the optical switching system that will permit parts of the computer to share information at the speed of light.

    In other breaking news electromagnetic radiation (read: electricty) doesn't travel at the speed of light! Coming Soon to Fox: When Reporters Get Confused

    At any rate that article was darn short on details, and the company's website wasn't any better. Anybody have any relevant data on exactly how fast this switching system is? I'm curious about their optical router at the heart of the system as well. It is my understanding that the slowest part of any fiber-based system is the router since the signals must be converted from light to electrical than back to light signals again. One would assume that such a design would be entirely too slow to be used as a bus. Of course, I may be entirely wrong...
    • No you're confused (Score:2, Informative)

      by citanon ( 579906 )
      Electrical signals travel at around 1/10 the speed of light.
    • Dispersive media spread impulses. The longer the line, worse the spread, longer the t delta to prevent taking a 1 for a 0 (intersymbolic interference). Coax, waveguides, bifilar couples are dispersive and carry low-freq em waves setting a nasty lower bound on bitrate. Optical WG are the same but max out well within the THz range (serial!) + you can color code signal (multiplex)

      Ciao
    • In other breaking news electromagnetic radiation (read: electricty) doesn't travel at the speed of light!

      In even more breaking news, Slashdot posters stick their feet in their mouths up to the knee.

      Electromagnetic radiation isn't electricity, it is light (and associated photons at wavelengths outside the visible portion of the spectrum).

      • by Hal-9001 ( 43188 )
        Strictly speaking, light is a subset of electromagnetic radiation. Thus all light is electromagnetic radiation but, as a general rule, not all electromagnetic radiation is considered light.
  • I'd like to see a beowulf...
    Oh, nevermind.
  • Hooray (Score:5, Informative)

    by Adam9 ( 93947 ) on Monday November 18, 2002 @08:32PM (#4702922) Journal
    Yay for free subscriptions.. here are some other [iht.com] sources [asia1.com.sg] for similar reportings that don't require evil subscriptions.
  • by Boone^ ( 151057 ) on Monday November 18, 2002 @08:37PM (#4702945)
    This would be a network of computers, not a supercomputer. The definition is becoming more lenient, so in a few years everyone on the internet will be a node in the world's largest (and only) supercomputer, and 80% of them will be redundantly running through Windows DLLs. Yay.
  • Optical routing (Score:5, Informative)

    by ctar ( 211926 ) <christophertar@gma i l . c om> on Monday November 18, 2002 @08:37PM (#4702946) Homepage
    The idea of optical routing is that, even in typical gigabit or any optical based networking media, the bottleneck is the processors in the routers. This is because the light must be converted to electrical signals, and then routing decisions and switching are done on the processor of the router. After being processed, the signals are converted back to optical to be sent out the appropriate port.

    Optical switching means that the light coming in on fiber from different devices is never converted to electrical to be routed. The actual light signals are switched from port to port. This was originally planned to be done with very small mirrors! (no joke!) which would aim incoming light to the corresponding outgoing port.

    According to the whitepaper on Chiaro's website, they have found a way to avoid the mirrors (which have an obvious bottleneck themselves, as well as potential mechanical failure) and they are able to multiplex or switch the light based on applying an electrical field to some of the optical components which them changes the angle and therefore the destination of the light.

    • I follow your description and it jives with me on how they can avoid the Optical-Electrical-Optical (O-E-O) conversion problems in the core of the router. But here's the part that from the article that I did not quite get:

      "The optiputer will initially consist of about 500 processors linked via the optical switching system that will permit parts of the computer to share information at the speed of light."

      Precisely how will the processors connect to the optical lines? Will there be some optical transceiver connected to the front side bus? Do the processor pins wire directly into the transceiver?

      Anyone know this part of the setup???
      • From the sounds of it this is more of a cluster type supercomputer. Thus the connections would be via some sort of converter at the actual nodes. Well thats my guess anyway.
    • According to the whitepaper on Chiaro's website, they have found a way to avoid the mirrors (which have an obvious bottleneck themselves, as well as potential mechanical failure) and they are able to multiplex or switch the light based on applying an electrical field to some of the optical components which them changes the angle and therefore the destination of the light.
      Electric field changes the angle? Sounds like a some sort of electro-optic modulation using crystals, similar to liquid crystal displays in calculators. Just use polarizers and change the angle of polarization of the incoming light to route it. But what the hell do i know, I didnt read the article >:D
      -brandon
    • tiny mirrors are MEMS. MEMS work well (in small quantities). They don't suck.
    • Re:Optical routing (Score:5, Insightful)

      by irish_spic ( 18702 ) on Monday November 18, 2002 @10:48PM (#4703506)
      I agree with what you are saying, but what you describe is an optical switch not an optical router.
      (a switch switches circuits or light channels in this case and a router routes packets).

      I read trough their website (www.chiaro.com) but wasn't clear on how they can identify the destination addresses of the packets (essential for routing) without some sort of photonic-electrical conversion. Then it won't be an all optical router, would it? ;-)

      cheers,
      Frank
      • I think there are obviously a lot of details left out as to how this optical technology actually interfaces with the 'processors' of the nodes...

        If we assume router means IP, and switch means Ethernet, than the difference between a router and a switch is very small nowadays...

        The major difference is that a router typically re-addresses the source and destination of the lower layer protocol before forwarding to the appropriate port, while a switch will just forward to the appropriate port without changing anything. Both make a forwarding decision, however, based on the destination address (MAC or IP).

        As to how either of these would practically work in this technology, I have no idea ;)

    • This was originally planned to be done with very small mirrors! (no joke!) which would aim incoming light to the corresponding outgoing port. ...they have found a way to avoid the mirrors (which have an obvious bottleneck themselves, as well as potential mechanical failure)

      You make it sound like such tiny mirrors would not work... In fact, the DLP projector in my living room has around 800,000 mirrors in it, all on a DMD chip. Sure, bending the optics as Chiaro does is cool, but I don't think it is necessarily any faster or more reliable than mirror based optical switching/routing.
  • by Jah-Wren Ryel ( 80510 ) on Monday November 18, 2002 @08:38PM (#4702952)
    Most of the key people at Chiaro are people who jumped ship from Convex Computer after they were acquired by Hewlett-Packard back in the mid-90s. Convex's claim to fame was to have invented and productized the first mini-supercomputer hitting the sweet-spot between the biggest vax and the smallest cray and they were very successful for about a decade.

    Larry Smarr, of UIUC's supercomputing center (aka the place where Mosaic was developed) has always been a big fan of the Convex crowd.

    Another bit of trivia - Jeff Christenson, of PERL fame is a convex alum as well as Dave Taylor of Id Software fame and a whole host of other key people now scattered about the world.
  • by toupsie ( 88295 ) on Monday November 18, 2002 @08:42PM (#4702973) Homepage
    Forbes is reporting: [forbes.com] ASCI Purple will run at 100 teraflops, or 100 trillion calculations per second, 8 times faster than its current supercomputer ASCI White and at a speed equivalent to the human brain, IBM said.

    HAL will be born a few years late...

    • "at a speed equivalent to the human brain"

      Before or after the six pack?
      • I mean, you pour a six pack on a computer, it just won't go as fast. OK, so you might need some work to beat the fault tolerance, but I'm sure you can find six parts that'll bring it down together.
    • by Waffle Iron ( 339739 ) on Monday November 18, 2002 @09:33PM (#4703195)
      speed equivalent to the human brain

      I don't know how he calculates that. Maybe that matches the raw number of logic operations of a human brain, but a digital computer has a completely different organization, so it's like comparing apples and elephants.

      The brain's advantage comes through the fact that the "logic" is embedded within and mixed up with an incredibly powerful fully associative storage system. The keys and values aren't little byte strings or numbers like digital computers use, but instead they are high-level concepts and experiences. We don't even know how to begin designing a direct emulation of this kind of hardware.

      OTOH, it might take someone 10 minutes to manually do a long division problem that the computer can solve in under 1 nanosecond. However, even with all of the awesome math throughput provided by supercomputers that consume tens of kilowatts of power, nobody's come up with a system that has the real-world common sense and precise realtime control capablities of a 1 milliwatt cockroach brain. (Did you know that they can fly? I discovered that one day by spraying one on the ceiling. Scared the living shit out of me.)

      Obviously, making speed comparisons between brains and digital computers is utterly meaningless when the fundamental operations they perform are so completely different.

  • by HappyCycling ( 565803 ) on Monday November 18, 2002 @09:07PM (#4703085)
    ...And it still gets Slashdotted...
  • by leeet ( 543121 ) on Monday November 18, 2002 @09:45PM (#4703237) Homepage
    Corect me if I'm wrong but I always thought SGI was using light in it's interconnectors between machines? That's how they can achieve amazing throughput.
    • Corect me if I'm wrong but I always thought SGI was using light in it's interconnectors between machines? That's how they can achieve amazing throughput.

      Optical fibre point-to-point has been around for years, it's often used to connect storage arrays to hosts. What the article is about is being able to switch and route optical data streams, which is an order or magnitude more complex. You see, it's easy to store an electronic signal in an electronic form, so a conventional router can stop a packet, look into it to work out what to do with it, then send it to the right place (or regenerate it on the right port). If you want to do that with light, you have to convert it into an electronic form, process it, then reconstruct the optical signal. An all-optical switch does away with the conversions. I'm not even sure if an all-optical (i.e. no electronics at all) router is even possible.
  • http://www.jacobsschool.ucsd.edu/news_events/news_ 2002/20021118.shtml
  • Is it really faster? (Score:3, Interesting)

    by El ( 94934 ) on Monday November 18, 2002 @10:22PM (#4703372)
    I was told by a fiber-optic transceiver engineer that signals actually travel faster in copper coax than in fiber (in both it's less than c, the speed of light in a vacuum). So couldn't you get even better results by hardware-switching a coax signal? And how usefull is only being able to talk to 1 other node at a time? Sounds to me like these guys have reinvented the T-bar used to connect IMB System 370 channels together... (albeit with much better performance).
    • The difference in propagation time is so low that for reaonable-length interconnects, it's going to be meaningless. Light travels around 186,000 miles per second, so under ideal conditions, a fifty-foot interconnect would take you about fifty nanoseconds. We'll use that for the example, it's plenty close for order-of-magnitude calculations.

      So, let's say that the difference in propagation speed between copper and fiber is 15%, which is probably pretty high. That would mean a difference of only about 8 nanoseconds.

      How much of a difference is that? Considering that the latency of the networking layers is generally measured in milliseconds, or if you're *really* fast, microseconds, that means that the extra latency from the fiber would be anywhere from 3 to 6 orders of magnitude LOWER than that of the networking layers. That's pretty insignificant.

      Now if you're talking about running a 1,000 mile interconnect, then the differences become pronounced - but trying to get any decent bandwidth out of copper at that distance is going to be impossible. Ten gigabits over long-haul fiber is commonplace. Currently, the 10 gigabit ethernet over copper attempts have been limitted to a few *feet*.

      steve
  • by Sponge Bath ( 413667 ) on Monday November 18, 2002 @10:23PM (#4703375)
    Because the previous attempt to implement a campus wide supercomputer using an RFC 1149 based network caused the pigeons to burst into flames.
  • There is still some room to grow left in the semiconductor business....but not much. Now that chip makers are near the limit in the "how small can I shrink it race", the goal now is to fit more die on single silicon wafer. As the "need for speed becomes more critical I think optical computing breakthroughs will become more common place as soon as the semiconductor business and research community start to move away from silicon semiconductors. When the focus on optic technology becomes dominant silicon chips won't go away, but they won't be as high tech.
  • look, fiber is awsome. it is not prone to electrical disruption like other digital media. plus, the speeds are very nice.
  • by daedel ( 625142 )
    Most 0 mods I have ever seen in a /. article. This must tell us something... Here comes another one.
  • by Animats ( 122034 ) on Monday November 18, 2002 @11:16PM (#4703641) Homepage
    This is an optical switch fabric, but it's still a few steps short of a router. Something else has to make the routing decisions and set the switches. It does the same job as the MEMS-type optical switch fabrics (the moving-mirror patchboards), but will switch in nanoseconds.

    The pure optical IP or ATM router is still years away. Optical computing isn't up to optical packet decode and route lookup. Optical buffering isn't ready, either, although you could potentially store packets temporarily in a fibre delay line.

  • While company calls it optical phased array, "array" only works with linearly increasing electric field, what turns it into just another case of diffraction, with "waveguides" being more like segments of diffracting material changing their properties each as a whole when electric field is applied (as opposed to pressure being applied in other devices). It would be more impressive if the device was purely optical -- if some material changed its properties based on the light applied to it, and bent another beam because of that change.
  • This reeks of Smarr, the man who ran an NCSA that did virtually nothing except some flashy demos and Mosaic. Mosaic being a project that was actively discouraged by upper management until it became too successful, whereopon they took credit. Smarr is a master politician, but lacks an eye for people and projects that accomplish something, rather than just looking superficially cool.

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