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Bell Labs Break Record With 31Tbps Via a Single 7200km Optical Fibre 125

Mark.JUK writes "Alcatel-Lucent's research and development division, Bell Labs, has successfully broken yet another record after it used 155 lasers (each operating at different frequencies and carrying 200Gbps of data over a 50GHz frequency grid) and an enhanced version of Wavelength Division Multiplexing (WDM) to send information at a staggering speed of 31 Terabits per second over a single 7200km long optical fibre cable. Previous experiments have been faster but only over shorter distances or by using a different type of fibre optic cable entirely."
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Bell Labs Break Record With 31Tbps Via a Single 7200km Optical Fibre

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  • Too bad (Score:5, Funny)

    by MrEricSir ( 398214 ) on Thursday July 18, 2013 @02:20PM (#44320073) Homepage

    Too bad the bandwidth cap is only 1 GB per month.

    • You are joking, but this is exactly how NBN in Australia works. Nationwide fiber network .. with data caps on INTERNAL traffic.

  • by cachimaster ( 127194 ) on Thursday July 18, 2013 @02:31PM (#44320217)

    Not wifi, wimax, 3g, 4g, ethernet, satellite, etc.
    All those tecnologies are just "last-mile" ways to bring data from this big pipes to the users. Internet is made of optical fibre.

    • Everyone knows the internet is a series of tubes.

      • by Anonymous Coward

        of course it's a series of tubes, tubes with optical fibres running through them...

      • Everyone knows the internet is a series of tubes.

        You mean it's not a big truck?

        • by gagol ( 583737 )
          Nah, it's a small box with a blinking led on top. It sits on top of Big Ben and only the elders of the Internet can allow access to it. (see: It Crowds)
          • ... small box... blinking led on top... sits on top of Big Ben...

            So... the TARDIS?


            Postscript: I've tried getting into that I.T. Crowd show, but it doesn't seem to be able to hold my attention.

    • by Kjella ( 173770 )

      Last decade called and want their post back, this decade fiber is your last mile. The rest is just for in-house distribution or on the go.

      • I work for an ISP. The vast majority of homes are still fed by copper/coax for the last mile. Fiber's expensive to install and it will be at least 10 to 20 years before it replaces significant portions of the copper out there.

        • by Kjella ( 173770 )

          Here in Norway we're up to 20% last year, it increases by about 3% per year (11->14->17->20) and all major rollouts (ex-DSL, ex-cable, ex-power companies) are doing fiber for new apartment buildings or housing areas. We're expecting major investments in fiber over the next years as the copper network has officially been declared a phase-out technology to be shut down in central areas by end of 2017 (first tiny test county has already shut down, it's now all fiber + mobile), it'll still exist as a l

  • Wonderful! (Score:3, Funny)

    by Anonymous Coward on Thursday July 18, 2013 @02:33PM (#44320255)

    Wonderful! Now my porn collection will download in mere MINUTES!

  • The question is (Score:4, Insightful)

    by maroberts ( 15852 ) on Thursday July 18, 2013 @02:33PM (#44320257) Homepage Journal

    ...whether a special type of cable was used, or whether just fitting different transmitters and receivers at each end of the cable will do the job without the need for putting down an entirely new fibre optic cable?

  • by timeOday ( 582209 ) on Thursday July 18, 2013 @02:39PM (#44320337)
    For comparison, Tokyo to Honolulu is "only" 6200 km (then 3900 from Honolulu to San Francisco). Washington DC to Paris is also 6200 km. So, as far the planet earth is concerned, it's a very realistic maximum distance of interest.
  • by NikeHerc ( 694644 ) on Thursday July 18, 2013 @02:43PM (#44320379)
    This was likely at the request of the NSA so they could download all our traffic quicker.
  • by Anonymous Coward on Thursday July 18, 2013 @03:11PM (#44320673)

    The switching is so dense and so fast, that the 7200km of cable has *in flight* 146 gigabytes of information at any given time. You can back up your typical "150GB" (143GB actual) OS hard drive and user data, and be done sending it before it starts reaching the other end (if you could buffer it to send that fast, naturally). Is that some crazy shit or what?

    • The switching is so dense and so fast, that the 7200km of cable has *in flight* 146 gigabytes of information at any given time. You can back up your typical "150GB" (143GB actual) OS hard drive and user data, and be done sending it before it starts reaching the other end (if you could buffer it to send that fast, naturally). Is that some crazy shit or what?

      Now that. That is impressive. It reminds me of those old mercury delay lines.

    • by DutchUncle ( 826473 ) on Thursday July 18, 2013 @04:02PM (#44321193)
      Back in 1979, when fiber was brand-new (and we were experimenting with speeds you wouldn't even bother with for TOSlink today), we hooked up a 5km spool of fiber to both sides of the same optical "modem". Using a Z80, we got an interrupt on the receive side apparently simultaneous (in the same clock cycle) to putting a byte in the transmit port - which sort of makes your DMA controller unhappy. Everyone figured there was a short or a cross-connection, because nobody could believe the speed. And that was a snail's pace in comparison to *each* laser of this system.
      • by mirix ( 1649853 )

        I can't see light in an old system being much slower, light is light right. If the fiber is fatter I guess it bounces more, taking a longer path.

        Data speed has of course improved, though, but that isn't strictly related. (speed of light affects the latency across the cable, whereas the data speed is all about modulation of the light).

        So light is 300,000km/s, I think they usually say speed in fiber is about 2/3rds.. so 200,000km/s... passing through 5km of cable in 25uS... which is fast, but ages in modern c

        • Yes, light speed hasn't changed; switching speed, however, has changed dramatically, and it's switching that gives you data rate. I think we were using 6 Mhz Z80s - the latest and greatest at the time (1979). Slip your decimal point 3 places to the left. :-)
    • by Smerta ( 1855348 )

      Reminds me of my first day (literally) on the job, out of school (EE/CE).

      Tech lead held up a one-foot segment of wire (about 30cm for you metric-minded folks).

      "Know what this is?"

      "Yeah, a piece of wire."

      "Yes, but it's also memory. This holds one bit." Then he held up a longer piece and said "And this holds a byte." Then he went on to explain (really, remind me) about propagation times, eye diagrams, etc....

  • Does this beat out the station wagon loaded with 500 kgs. of optical media averaging 50 km/hr?

    Units should probably be TerraBit / Sec / Km.
    • by jandrese ( 485 )
      Well, a blu-ray disc weighs about 16g and hold 50GB of data, so 500kg would be 1,562,500GB worth of storage. Your station wagon doing 50kph will need exactly 6 days to travel that for, or 518,400 seconds. In that much time, this optical link would have transferred 2,057,011,200GB.

      Your station wagon's bandwidth isn't even in the ballpark. Even if you use those super experimental blu-rays that hold 1TB each you aren't even getting close to the bandwidth of this link.
      • by AJH16 ( 940784 )

        If we make it SD cards, it's about 64 GB per gram. That's 500*1000*64 GB or 32 million Gigabytes. That works out to the equivilent of a 494 gigabit link, so yeah, even if we use a more realistic speed of 100km/h, we're still talking 30 times faster. Fill a tractor trailer would be faster though and a container ship full of SD cards is much, much faster.

      • by plopez ( 54068 )

        So how many station wagons would that be. Put it in terms we understand like "libraries of congress" storage, staion wagons of dvds for bandwith.

    • Worth checking: 16g/disc = 31,250 discs per 500kg payload. at 50GB/disc, that's 1562 TB or 12,500Tb/per payload. At 50km/hr, or 0.014km/s, I get 174 Tb-km/s

      So 31 Tb/s over 7200km is 223,200 Tb-km/s

      It looks rather biased in favor of the fiberoptic line. Moreso since stationwagons have particularly bad speeds when operated under water.

      • What I find interesting about this is, the old test involved a station wagon full of magnetic tapes. But allowing for technology advances in both media and telecommunications, it seems that telecommunications is winning the day. Though 155 lasers all running at different frequencies sounds pretty exotic but maybe you can just put them all on a few chips. (don't ask me to connect up all the fibers though!)
    • by hamjudo ( 64140 )
      The station wagon can outrun a backhoe.
    • by AJH16 ( 940784 )

      Optical media is less data dense than using magnetic disks or even SD cards. A micro SD card can hold more space than a blu-ray disk.

  • ...was I the only one who thought "31 tablespoons of what now?"
    • The day they can deliver tablespoons of *anything* through the net, some people will never leave their rooms.
  • Can I get the ISA version of the adapter card anywhere?
  • by michaelmalak ( 91262 ) <> on Thursday July 18, 2013 @03:44PM (#44320989) Homepage
    Did the test include a simulated NSA tap, to test the impact of that optical degradation?
  • Now we can get pr0n in 302976 x 170424 video at 25 fps. It will have to be uncompressed as I don't think we have anything that can compress it that fast.

  • No repeaters (Score:2, Insightful)

    This is the first time that transoceanic cables can be made that don't need repeaters. The speed is nice, but no repeaters mean that the cable will be a lot cheaper to build and has far fewer parts that can fail. It also won't be enveloped in an electric field that attracts sharks. And finally, it becomes a lot easier to upgrade the cable later: you only need to install new equipment at either end, and don't have to worry about the repeaters being compatible with the new signalling.

  • by azav ( 469988 ) on Thursday July 18, 2013 @04:57PM (#44321737) Homepage Journal

    Talk to me when it's 31 Tera Bytes.

  • by The Cat ( 19816 ) *

    It will never leave the lab.

    • by dww ( 119841 )

      It will never leave the lab.

      It will if it makes sense commercially. At the old STL (later Nortel) lab in Harlow England, where data transmission over fibre was invented back in 1966, we could show rates of up to 64 Tb were possible using DWM over a single fibre at least 12 years ago. But people weren't ready to pay for such data rates back then, and the telecoms market was crashing after the excesses of the late 1990's, so development was stopped.

As of next Tuesday, C will be flushed in favor of COBOL. Please update your programs.