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An optical transmission under the Atlantic at 100 Gbps – that sounds pretty cool, doesn’t it? Today, Hibernia Atlantic, a network operator and Chinese hardware maker Huawei did just that – the first 100Gbps optical transmission across the Atlantic. Infinera did the same under the Pacific.

An optical transmission line under the Atlantic at 100 Gbps – that sounds pretty cool, doesn’t it? Hibernia Atlantic, a network operator and Chinese hardware maker Huawei today did just that and conducted the first 100 Gigabit transmission across the Atlantic. The test was conducted over 5,570 kilometers between Halifax, Nova Scotia and Southport, England.

Infinera worked with Pacific Crossing to show off its long-haul undersea 100 Gbps technology under the Pacific ocean in October 2011. (Press release PDF) That subsea trial spanned more than 9,500 kilometers on Pacific Crossing’s PC-1 fiber from California to Japan and was the first and longest successful 100 Gb/s trial performed across the Pacific delivering digital coherent transmission. However, the sub-Atlantic trial could see a faster commercial deployment it seems.

The trial involved Huawei’s latest 100 Gbps single wavelength coherent technology. In addition to performing across distances greater than 5,000 km, the trial has successfully demonstrated long-term, error-free transmission at 100Gbps. Huawei also successfully demonstrated co-propagation of 100 Gbps wavelengths at 50 GHz spacing which enables future upgrades of subsea capacities up to 5 Tbps.

Michael Kennedy, principal analyst at ACG Research in an interview with Fierce Telecompointed out that”

“Coherent technology actually makes 100 Gbps cheaper than non-coherent, though for now it is more costly because it’s a newer technology. With coherent, think of it as a light beam with all of the light tightly aligned, but with non-coherent, the light would be more diffused. The coherent beam would look like a pen light if you shined it at the moon; the non-coherent would be like a flash light. Coherent reduces the need for amplification and increases the distance. It reduces chromatic dispersion, so you can have wavelengths set closer together, and you would need fewer sub-channels.”

Writing in the same Fierce Telecom article, Dan O’Shea noted that 100 Gbps would make its impact mostly in long haul networks as metro networks have different economics. The success of this trial is allowing the companies to move forward on their aggressive deployment schedule, including 100 Gbps connections between Halifax and Montreal and between Amsterdam and London by Q1 2012, followed by other key routes later in the year, Hibernia said in a statement. We are slowly but surely inching towards mass scale deployment of 100 Gbps technology in the long haul networks. But then we have been saying that for a long time. Finally, the real world is catching up.

  1. I’m sorry, but that is a misleading explanation of coherent vs. non-coherent transmission. Coherent transmission requires a local oscillator, in this case a laser at near the same wavelength*, at the receiver. The receiver then compares the received light with the local oscillator to extract the signal. (To be precise, the coherence refers using the carrier phase information from the light from the transmit laser = carrier signal). In non-coherent transmission, the carrier phase information is not required and the amplitude of the incoming light is used to decipher the signal.
    *Proximity to the carrier wavelength signifies whether the system is homodyne vs. vs. heterodyne. Suggest visiting this site for a much more detailed & likelier clearer explanation of coherent transmission.

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  2. Although the cables now are optical and modern undersea robots do the work, does still having to rely on submarine cables to carry the bulk of the Internet traffic between land masses, 170 years after first invention, qualify as steampunk?

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