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Researchers Transmit Optical Data at 16.4 Tbps 2550km 126

Stony Stevenson writes "The goal of 100 Gbps Ethernet transmission is closer to reality with the announcement Wednesday that Alcatel-Lucent researchers have recorded an optical transmission record along with three photonic integrated circuits. Carried out by researchers in Bell Labs in Villarceaux, France, the successful transmission of 16.4 Tbps of optical data over 2,550 km was assisted by Alcatel's Thales' III-V Lab and Kylia, an optical solution company. The researchers utilized 164 wavelength-division multiplexed channels modulated at 100-Gbps in the effort."
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Researchers Transmit Optical Data at 16.4 Tbps 2550km

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  • by davidwr ( 791652 ) on Thursday February 28, 2008 @09:43AM (#22587242) Homepage Journal
    What's that in Library-of-Congresses per fortnight?
    • by CRCulver ( 715279 ) <> on Thursday February 28, 2008 @09:53AM (#22587348) Homepage
      Is that a laden European or African library of congress?
    • Re: (Score:2, Informative)

      by pizzutz ( 1175903 )
      I calculate roughly 248,000 Library of Congresses per fortnight.

      Curse my geeky genes for making me calculate that when you asked.
    • Re: (Score:1, Insightful)

      Or how many 747's full of DVD's?
      • Re: (Score:3, Funny)

        by suso ( 153703 ) *
        HD DVD, Bluray or regular?
        • Either way, I think my file server needs more space.
        • I prefer HHDD-DDVVDD, thank you.

          HD DVD, Bluray or regular?
        • Re: (Score:3, Informative)

          by networkBoy ( 774728 )
          Data per boeing 747 (LCF version)

          DVDR = 159238213.7 GB/747LCF
          HDVD = 677609420 GB/747LCF
          BDVD = 847011775 GB/747LCF

          • Re: (Score:3, Interesting)

            by fbjon ( 692006 )
            Your calculations are a bit off. The LCF, like the Beluga and similar, is meant to transport aircraft parts which are large, not heavy. Additionally, the bulky airframe means it can actually lift less weight than a regular cargo carrier, and maximum takeoff weight is the limitation for bandwidth, not volume. Besides, the LCF is not for sale to customers.

            Redoing for the 747-400ERF:

            • Assume each disc weighs 16g, like a CD.
            • This gives us a box with a volume of 1,38 m^3 that contains 80000 discs, weighing 128
            • by kesuki ( 321456 )
              I'm assuming you're using dual-layer media, but technically, bd-rom and such support Dual sided, dual layer media, as dvd also supports. of course finding writable dual layer dual sided media is different, but assuming you used standard manufacturing of pressed blue ray drives, you could use dual sided dual layer media. that effectively doubles both your figures for bd-rom and dvd-rom (unless you considered the dual sided capabilities i didn't check your dvd numbers)
      • Let's just say it's a lot of pr0n.
      • by Eddi3 ( 1046882 )
        Well, I'm not exactly sure what you're asking, but here we go:

        (((650 / (0.0014 * .12 * .12)) * 8.54) / 1024) / 1024 = 262.591574 Petabytes

        650 cubic meters - rough volume of 747 [1] .0014 meters - rough thickness of DVD .12 meters - diameter of DVD
        8.54 GB - dual layer DVD capacity
        1024 GB in 1 TB
        1024 TB in 1 PB

        So, a 747 can carry about 250 Petabytes of data in Dual Layer DVDs at a time. Then just divide that by the time it takes to fly it wherever you want it.

        [1]: All volume values for the 747 were found at h []
        • Unfortunately, according to that page, the max payload weight is 66,300kg, and DVDs weigh about 17 grams, meaning you're limited to 3.9 million DVDs = 31.763 PB.

          Unless you plan on taxiing all the way there.

    • by Eddi3 ( 1046882 ) on Thursday February 28, 2008 @10:10AM (#22587502) Homepage Journal
      (14 * 24 * 60 * 60) / (20 / 2.2) = 123,984 LoCs/fortnight

      (total seconds per fortnight)
      14 days per fortnight
      24 hours per day
      60 minutes per hour
      60 seconds per minute

      all over

      (seconds per Library of Congress transferred)
      20 terabytes per second (one LoC/second)
      2.05 terabytes per second (16.4 terabits per second
    • by u-235-sentinel ( 594077 ) on Thursday February 28, 2008 @11:26AM (#22588414) Homepage Journal
      What's that in Library-of-Congresses per fortnight?

      Well... if you are Concast they will give you those numbers in terms of photos or mp3's or emails downloaded in a month.

      Personally I like to know in terms of how many 8 track tapes I can download a month. ;-)
    • What's that in Library-of-Congresses per fortnight?

      Assuming you want a copy of the LoC which will allow you to reconstruct the entire collection [], you'll need scanned images of all the documents, decent MP3 (or ogg) files of the audio recordings and at least SD-quality copies of all the video. That would require something north of ten petabytes. At 1.64Tbps, that would work out to less than 25 LoC/fortnight--and that's assuming Mom doesn't pick up the kitchen phone and kill your connection.

    • by VE3MTM ( 635378 )
      No, the real question is: is it faster than a station wagon full of Blu-Ray discs on the highway?
    • How about channels of high definition video? High def television broadcasts are 20 Mbps. So this technology can simultaneously transfer 820,000 high def channels over a single optical fiber.
  • by r_jensen11 ( 598210 ) on Thursday February 28, 2008 @09:43AM (#22587246)
    Would this qualify as 11?
    • by suggsjc ( 726146 )
      For now...wait a couple of years and it will be a measly 5-6. Not sure what we are going to do with all of that bandwidth, but I'm sure that we'll come up with something interesting and possibly even useful.
  • CPU speeds? (Score:1, Interesting)

    by Anonymous Coward
    Surely there must be some incredibly processing power behind transmission speeds like this? Anyone one have any idea?
  • ObWalken (Score:4, Funny)

    by Saint Aardvark ( 159009 ) * on Thursday February 28, 2008 @09:50AM (#22587314) Homepage Journal
    <walken>That's a lot of cows. []</walken>
    • Be honest, how many of you followed the link above, but the first thing you looked at was the picture with the two women and Dwayne Johnson. (Ok, now be honest, how many of you followed the link after I mentioned Dwayne Johnson or the two women?)
  • by geminidomino ( 614729 ) * on Thursday February 28, 2008 @09:51AM (#22587322) Journal
    That's just BURST throughput. Depending on factors like time of day, how many other users there are, and environmental conditions, throughput may drop as low as 33kbps. And we do NOT filter bittorrent.

    Just check your TOS agreement. It's all right there.
    • by holyspidoo ( 1195369 ) on Thursday February 28, 2008 @11:28AM (#22588428)
      Now offering the fastest 16.4 Tbps service* available anywhere

      *1 Gig upload/download monthly limits apply

      • I know you're joking but my ISP is now offering a 50Mbps with a 50GB limit [] download/upload combined. 1.50$ per additional GB, no limit.

        Remind me again who needs a connection that can only work at 100% capacity for a little more than 2 hours per month ? Only to be charged 50c/s afterward (no limit !!!)

    • Pitty the net is so slow. 16 Tbps connection from the phone company to my house, yet download speeds still rarely top 600k a second. Difference between now and before is I can now download 1,000 files in 30 minutes instead of just one file in 30 minutes. Sigh. Of course, with Bittorrent and dedicated Usenet servers, I can get much faster downloads. Hmph, maybe iTunes will start offering downloads at 320kbps on their songs and full 1080p on their movies.
  • On Neutrality (Score:2, Insightful)

    by Anonymous Coward
    In other news: American telcos wonder how French providers are able to afford research and development without additional funding from a tiered billing billing scheme that is needed to advance the science in the United States.
  • With the ever-predicted bandwidth crunch always just around the corner, can existing cables be reused just by replacing the signaling equipment at substations with this? If we don't have to lay all new cables - just upgrade the nodes - then upgrading to these bandwidth capacities on our current networks would be a cinch.
    • Re: (Score:3, Informative)

      by afidel ( 530433 )
      The problem has never been the glass! There is absolute craploads of dark fiber just about everywhere. Last time I saw stats it was something like less than 1/3rd of installed fiber was lit up. It's the uber expensive routing equipment needed to keep up with the flood of data that's the expensive part.
      • That, and the last mile (or even the last 25 feet) to YOUR house.

        (I've always seen that quoted as "Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge" But yeah, that.)
  • by the_mind_ ( 157933 ) on Thursday February 28, 2008 @09:55AM (#22587368)
    "164 wavelength-division multiplexed channels modulated at..."

    how very Star Trek of them.
    • by pizzutz ( 1175903 ) on Thursday February 28, 2008 @10:07AM (#22587482) Homepage

      "164 wavelength-division multiplexed channels modulated at..."
      how very Star Trek of them.

      I'm sorry Captain, but we canno' reach these speeds with time-division multiplexing. the phase coils canno' handle it!
    • by funaho ( 42567 )
      A soon as they can get the multimodal reflection sorting working we can tap into the Borg collective. They have all the good warez, pr0n, music and movies from thousands of civilizations. :)
    • Re: (Score:2, Interesting)

      To be honest I don't find this *that* amazing.

      I worked at the victim-of-the-telecoms-bubble that was Marconi 2000-02 and there was a bit of kit, the snappily titled UPLx, that could deal with 160 10Gbps channels down a pair of fibres, unregenerated over about 1000km - using soliton wave shaping and some sodding great Ramen pump laser to get there (nothing to do with noodles before you ask). It was demoed in the labs reliably, and I believe sold in to Telstra Australia

      In 5 years, they've added 4 Gbps ... wow
  • Tbps speed, and over 100 Gbps. Something is wrong here.
    • by spectrokid ( 660550 ) on Thursday February 28, 2008 @10:11AM (#22587512) Homepage
      They had 164 lasers with different colours sending 100 Gbps EACH over the same fiber, splitting the colours apart again at the other end with what probably is a little more advanced than a prism.
      • Re: (Score:2, Informative)

        by EricR86 ( 1144023 )

        I'd wadger they're using devices like a Diffraction Grating [] or a Fabry-Perot Etalon []

        Only a little more complicated than a prism :)

      • by colinmcnamara ( 1152427 ) on Thursday February 28, 2008 @12:28PM (#22589190) Homepage
        Its called dense wave division multiplexing, or DWDM. You take independent links (in this case 100Gig links), and transmit each of them on a slightly different wavelength of light called a Lambda. Since optic is looking for a specific wavelength, you can now run many "virtual links" per physical fibre. This is the standard technology for most Telcos. The innovation here is that they are doing this with 100Gig transceivers, and they have chipsets fast enough to combine the different lambda's back together into on high speed link. And yes, you can now let the Lambda Lambda Lambda jokes fly
    • 100 Gbits/sec * 164 laser colours sent over a single pair of fibers = 16,400 Gbits/sec total throughput.
      16,400 Gbits/sec = 16.4 Terabits/sec
      16.4 Terabits/sec / 8 bits = 2.05 TeraBytes /sec

      If you think about it, this is like shipping 2x 1Terabytes hard drives accross the Atlantic in 1 second.

      Now if you want the SneakerNet comparison... or perhaps JetNet in this case....
      Say you could fit 10,000 x 1TeraByte hard drives in a 747 air plane, and it takes you 6 hours to cross the Atlantic.
      6 hours= 21600 seconds
  • error checks? (Score:1, Interesting)

    by sjs132 ( 631745 )
    Slim article... How long would it take to error check that much data?

    on Another note... What did they do with all that Pr0n once it got to the other end?
  • But what is the latency involved in a system like this? Right now I get about 25000kbps and that is plenty for me, but what I really need is reduced latency for real time simulations.
    • Well the optical transmission would go nearly the speed of light, but I'm not sure how fast the transmitter and detector can keep up with splitting and recombining 164 channels of data.
      I'm sure this is being looked at as a means of an intercontinental backbone, rather than something coming into your house.
  • by ScaryMonkey ( 886119 ) on Thursday February 28, 2008 @10:04AM (#22587452)
    No matter how much speed they create, they will still be subject to the Law of Diminishing Porn Returns, which states:

    For download rate n, my demand for new porn will require me to download at a rate of n+1.
  • Where I the only one thinking a truck filled with DVD's when the headline said optical data?
  • Jeepers, that's really cool.

    Meanwhile, I can't even get FIOS service in Philadelphia, one of our major cities, despite my keen desire to purchase it.
    • really, because I'm out in doylestown, and I have it. 5/5. and I'm very happy.

      of course I forgot to pay my bill for a couple months, so they aren't happy with me...but it is still working, so whatever.
  • the title says 100 Gbps
    the article says approx. 16 Tbps
    and the last sentance says how close we are to creating 100 Gbps ethernet and describes how the terabit link was created using multiplexed signals at 100 Gbps.
    so what the heck am i missing, because im confused as hell
    • by Detritus ( 11846 )
      DWDM []
    • The cable (fiber optic) has multiple lasers sending through it at once (multiplexing). So a single laser could operate at 100Gbps, but 164 of them at once... well...

      They just use different "colors" of lasers for each 100Gbps signal.
  • Part of the Ethernet spec [] is to wait 9.6 microseconds after the medium appears to be idle before sending, then resend if it collides. Light moves about 3 kilometres in that time. Making an Ethernet of 2550 km pratically guarantees nothing but collisions. So while this is a hunkin' heap of net, it's not Ethernet.
    • by funaho ( 42567 )
      Well in order to have collisions you need at least two transmitters on the same medium, and this is a point-to-point full duplex fiber connection; there can't be a collision because the two ends transmit on opposite fibers. It undoubtedly required some serious TCP/IP tweaking through to take advantage of that throughput.
  • Hilarious... The fortune that I had at the bottom of the comments for this artcle:

    There is more to life than increasing its speed. -- Mahatma Gandhi

    Did someone plan that?
    • - Did someone plan that?

      Here is mine:

      To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection. -- H. Poincar'e
  • The movie industry just shat a brick.

  • swift kicks in the groin, when all you get at the house is a "blazing" fast speed of 26.4 Kbps on dial up. Thank you Verizon, fucking thank you... ISDN is not even an option where I live.
  • Let me see if I got this right... They made 164 lights of different color blink very fast and very far. Why can't Slashdot summarize things better?

"The one charm of marriage is that it makes a life of deception a neccessity." - Oscar Wilde