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The 1st Commercial-Grade All-Optical Switch?

joabj writes: "Today's Washington Post trumpeted the delivery of the first-ever commercial-grade optic-switch, by Corvis Corp. I'm not sure how commercially viable a switch the size of a refrigerator can be, though a commercial-grade all-photonic switch is indeed, as the WP points out, a "holy grail" of the optics industry--the missing piece for the 40-80 Gbps throughput for fiber optic cable that the industry is so hungering for these days. (Now, photonic signals must be converted into electrical signals to be switched, then back into light again -- slowing transmission speeds considerably.) Unfortunately neither the article (Free reg. req.) nor Corvis' own Web site explains what the winning technology was. There are a lot of competing ideas out there on how to switch optical signals. Is it MEMs? Liquid crystals? Curious minds want to know ..."

Initially, this sounds a lot like the optical switch announced by Agilent a little while ago, but with the bonus of being ready "within a few weeks" from workaday life. (Does that mean the equipment reported as delivered is still being installed or set up?) [Updated 11th Oct. 2000 4:05 GMT by timothy:] As a few people have pointed out in comments, that free registration is pretty painless ... since it's not necessary. Better than the other way around! ;)

27 of 73 comments (clear)

  1. small unimportant note -- by pezpunk · · Score: 2

    there is no free registration required for the washington post. you're thinking of the new york times.

    Internet killed the video star,

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    i could live a little longer in this prison
  2. Switching method by Tim+Macinta · · Score: 2
    Unfortunately niether the article (Free reg. req.) nor Corvis' own Web site explains what the winning technology was. There are a lot of competing ideas out there on how to switch optical signals. Is it MEMs? Liquid crystals? Curious minds want to know ...

    It's something which when revealed will be "obvious" to everyone on ./ and which has plenty of prior art. Just kidding (I agree that most patents which appear on ./ are absurd, but if this company patents the technique that they used to make their switch it at least sounds like it would be a good use of the patent system for once).

    1. Re:Switching method by appsbs · · Score: 2

      Could it be here?

  3. Probably Microscopic Mirros by tylerh · · Score: 5
    The article says:
    Lucent...said it delivered a similar all-optical technology...last month to Global Crossing
    Lucent says here they are using microscopic mirros, so corvis probably is too.
    --
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    1. Re:Probably Microscopic Mirros by fatphil · · Score: 2

      It's non-linear optics.
      Basically if you pump the signal beyond the normal linear behaviour you an get different frequencies to behave completely differently from each other. You can get a "mirror" using total internal reflection for any single frequency in the FDM.

      Non-linear here means that when you add the signals together you don't get the sum of the inputs as the output!

      FatPhil

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      Also FatPhil on SoylentNews, id 863
    2. Re:Probably Microscopic Mirros by Puk · · Score: 5

      The biggest problem with all-optical switches isn't the routing of the optical signals. They have several technologies, including MEMS-controlled mirrors, for doing this right now. Optical cross-connects are commercially available (though expensive) products.

      The difficulty with optical switches is in determining _where_ to switch the data without converting it to the electrical domain first. Plenty of schemes have been proposed where the data goes O->E to read the headers and decide where to switch it, and then optically switches the packet farther along the path (where the actualy signal of the packet never left the optical domain), but no one has come up with a switch that does it _all_ in the optical domain. Admittedly, few if any of these "mostly-optical" systems have been built.

      I'm not sure what Lucent and Corvis have done. It sounds to me like they have probably implemented one of these systems. They claim it's "all-optical", but I doubt that they have built this without at least the headers being converted to the electrical domain. Even so, it's an impressive achievement to have made a commercially viable product which does that much. It remains to be seen which way will end up being more cost-effective in the long run. After all, that's what matters in the industry. :)

      -Puk (Yes I'm Probably Wrong)

  4. Already Competitors... by Lostman · · Score: 2

    A very interesting article at http://biz.yahoo.com/prnews/000828/nm_lpth_ne.html reports how LightPath Technologies released its Optical Switch at the National Fiber Optics Engineers Conference in Denver, Colorado. Hmm, wonder what this will bring -- lower pricing or a law suit?

  5. Lucent also claims first. by NetWurkGuy · · Score: 2

    http://inside.bell-labs.com/headlines/2000/august/ 1/bln1.html is the url

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    "Obtuse Anger is that which is greater than Right Anger" - Lewis Carroll
  6. First to Market by 1alpha7 · · Score: 2

    I'm not sure how commercially viable a switch the size of a refrigerator can be . . .

    The need to be first to market is likely the major reason for the size. Comments like

    "For the last six to eight months, this has been an industry of warning shots by all sorts of optical-equipment companies,"

    and

    At least one Corvis rival takes issue with the company's first-to-market claims. Lucent Technologies Inc. said it delivered a similar all-optical technology for commercial use last month to Global Crossing Ltd

    make it clear that first to market was first on their minds. The size wil probably drop by half every 8-12 months.

    1Alpha7

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    1. Re:First to Market by appsbs · · Score: 2

      Make sure you partition the fridge off from the switch. All that light flinging around in there might skunk the brew.

  7. Oh yeah? by glowingspleen · · Score: 2

    You think that optical switching is neat? You should see me do it. I just take some crack and hold onto a light switch...

  8. Commercial switches vs. prototypes by joabj · · Score: 4
    There are a lot of all-optical switches out there that are being worked on. In addition to Agilent, I can think of recent announcements by Chorum, SpectraSwitch, CoreTek, Nortel, and Tellium's optoelectronic hybrid model. . . .

    Personally, I take announcements of prototypes such as those above with a grain of salt. A prototype is still further away from production than most people realize. You can pretty much do anything you want within the limits of physics, given a big enough R&D budget (and snazzy enough PR department to tout your work). But for your prototype to A: work *all* the time in the field, B: and for a competitive price, and C: to be compatable with existing standards, are the hurdles that kills 99.5% of all new technologies. . . joab

  9. Only a geek could love by dustintodd · · Score: 3

    This area of technology is so full of hype and marketing lingo it is hard to sort fact from fiction. Are they first? So what tomorrow someone else will be second with bigger this or that. I would not attach too much importance to the fact that a reporter got duped in to believing this was the "holy grail".

    But it is so interesting that optical switching has become the rock star of the day. Because essentially these are very low intelligence switches that perform very cool optical tricks. These devices are essentially circuit switched devices. But even that is probably too much credit they are static circuit switched devices. Because optical paths are setup by a network administrator. An IP router or carrier voice switch are far more intelligent then one of these devices. No one gets excited about add/drop muxes anymore but I am sure in their day it was big deal. Add/drop muxes became a commodity, just as optical switches probably will become some day. These devices, along with IP routers, ATM switches, ethernet switches, sonet muxes, dwdm, etc... are low glamor working class equipment of the carriers networks.

    The most interesting part is the ability split out or splice in individual wavelengths, neat trick.

  10. Data Switch vs Telecom Switch by Gumby · · Score: 4

    One big issue with these optical switches is that they don't switch packets, they make persistent connections like a phone call. So optical data passes through cleanly, to ONE place. So this doesn't accomplish the function of a network switch at all. They're electronically controlled, so it's a lot better than manually re-routing a fiber patch panel, but that's all they do.

    1. Re:Data Switch vs Telecom Switch by Animats · · Score: 2

      You can architect a packet net around a slow circuit switch. The general idea is that you open up more or fewer circuits between the edge routers based on traffic level, so that effectively the backbone gets reconfigured as the traffic changes. This reconfiguration probably takes place on a scale in the range of seconds, far slower than the per-packet time.

    2. Re:Data Switch vs Telecom Switch by Graymalkin · · Score: 2

      Packet switching is incredibly slow compaired to circuit switching for data transfer. Sure a circuit takes a millisecond or so to switch while ackets can be switched thousands of times per millisecond. The power of circuit switches is you only need to make the switch once. If I send you something on a packet switched network every single packet needs to be switched and routed which not only increases the lag of the signal (so much time per hop) but you also face the chance of packets taking a slow path or never reaching their destination. Packet switching has incredible overhead. With circuit switching after the connection is made you've got a steady strait line to your destination. Instead of driving blindly on side streets you're cruising on your own personal freeway. Part of the speed from the Internet 2 (the exclusive realm of a couple corporations colleges and research labs) is that it is mostly circuit switched optical networks. Packet switching is more amorphous and came about due to the lack of reliable connections between early networked computers. Circuit switching can be designed to be as amorphous and is a bit more reliable for long information hauls.

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  11. Another link by Ross+C.+Brackett · · Score: 3

    Be sure to check out this article in Wired from a few months back about using porous crystals to do an all-optical switch that is also solid state. Apparently older models used thousands of little rotating mirrors! The same technology can be used for regulating other kinds of waves including sound waves and wave waves (like in the ocean).

  12. Re:My Gawd! by talesout · · Score: 2

    I believe that with everything you just said, you were actually trying to say: "Why did this get posted to Slashdot?"

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    Bite my yammer.
  13. Re:I got it... by jafac · · Score: 2

    That's still opto-magnetic. or even opto-mechanical.

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  14. Corvis has a law suit filed against them already.. by Lostman · · Score: 3

    An article at http://www.ciena.com/news/archive/2000/07/07.19.20 00pr.html explains how CIENA has already filed against Corvis charging that Corvis violated 3 patents relating to CIENA's optical networking communications systems and technology.

    How this will effect the switch is unknown as of yet.

  15. Some real information.... by Doco · · Score: 5
    First off go to LightReading.com to get some general information on this technology arena.

    Corvis's switch is an all-optical switch. No eletrical regeneration involved. What it is switching is wavelengths of light. NOT packets. So, you can take a wavelength of light from one fiber and send it out another. This allows you to set up 2.5Gbps (OC-48) circuits quickly.

    What technology are they using - don't won't say. Almost all other people in this arena are basically splitting the dense-wave-division-multiplexed (DWDM) circuits into their individual wavelengths. Then routing them through micro-mirrors. The micro-mirrors allow you to connect any two fibers together optically. Then, the outputs from this are re-combined, optically amplified and transmitted.

    This isn't for sure what Corvis is doing - but I would bet money that this is basically what they are doing.

    One problem with this is that you can't have two circuits on a fiber using the same wavelength of light. So, you would need something that shifts the wavelength of light being used. Nobody that I know of has a commercial product to do this.

    Press blurb about this particular thing is available in a Light Reading article.

    A couple of weeks ago, Corvis announced that they had revenue - from this shipment of course.

    One more link - Some hints to what technology they are using.

  16. Probably requires a new kind of encoding! by 2nd+Post! · · Score: 3

    It occurred to me that the O->E conversion may be skipped entirely if the O data is encoded in such a way that the 'header' can be read without doing some sort of fancy decoding, interpretation, then switching.

    Of course, this brings an optical switch into the realm of analog computing, instead of digital, but hey...

    Dunno if this is even possible inside of a fiber, but can one encode a holographic signal into the header? This depends on the signal being coherent in the fiber, but if you can take the signal and recombine it with a similarly coherent signal, you can get data out. This data is still optical, perhaps in the form of a grid pattern(barcode here!) which can be read and interpreted. At this point it would seem an electrical device is still needed to operate the switch...

    I dunno, how do they really encode this information? Just binary pulse data?

    The nick is a joke! Really!

  17. Different Freqencies... by HaeMaker · · Score: 3

    I believe this works, not by using a header to assign an address, but by assigning a freqency to a destination and that frequency is then switched optically.

    The first switch reads the header and assigns the frequency, then the subsequent switches simply switch based on frequency (never reading the content of the packet). Then the last switch, (who owns that frequency) then converts it to electricity and sends it over the regular network (i.e. like ethernet...)

    One day, we will all be assigned frequencies like we are assigned IP addresses and all info will be transported by fiber.

  18. You lot amuse me sometimes :-) by philj · · Score: 2

    I'm not sure how commercially viable a switch the size of a refrigerator can be

    That's because you don't know what you're talking about! Do you think that a company that can afford a switch this size cares that it's this "big"? You've obviously never seen how "big" a good unix box is.

    PS: Moderators: It's not flamebait, I have a clue....

  19. Stock price by Anonymous Coward · · Score: 4

    This is just pure stock ramping. I wish it was true as I have some friends at Corvis, unfortunatly, the switch is a long way off. Management wanted to release this PR after a concept trial that was sucessful, this switch is at least 5 months way from market + it's NOT all optical as headers are converted to good old fashioned electrial signals, the switching path is determined and then the packet is switched via MEMS tech.
    Lucent is the closest to an all optical switch followed (a fair way back) by an English company call goouch and housego (I think the spelling is slightly off there).

  20. Optical logic gates coming out of the labs by kobotronic · · Score: 2
    All this talk about micromirrors .. mechanical stuff, seems like an inelegant solution, don't it?

    All-solid-state nonelectric optical computing (OC) with photon-controlled fast-acting logic gates must be part of the equation of tomorrow's terabit speed network nodes. They got stuff in the OC labs like special polymer material that acts like transistors but switches state faster - and conducts streams of photons instead of current - the stuff changes light transmission properties when a control photon source is applied. Nothing electrical in sight. You can build logic circuitry faster than anything electronic and certainly anything mechanical with this stuff.

    It'll likely be 'commercially available' eventually, in some form - it's nowhere near practical for use or miniaturization yet, but in the long run it may replace the electronic processors in our computers and move the OEO barrier so that the all-electronic components are used only for less-critical photon-source, I/O and storage systems, and then only swift photons move about inside and connecting the crystalline hearts of all things fast and digital.

    Sorta off topic, and much much slower 'technology', does anyone have any pointers to projects dabbling in fluid logic gates, using only the dynamics of liquids in ducts and valves to set logic states and act on them? The experiments with water 'transistors' I've heard mentioned used a control source of liquid to nudge a stream from one fork in the flow path to another.

  21. I believe I recall seeing PR ads on TV... by ca1v1n · · Score: 2

    ...from some huge communications technology company or another that was advertising a method using microscopic bubbles. I don't know if this is actually in production anywhere, since PR ads tend to be full of vapor, but that's another possibility for the switching method.