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Jun 10 2019

Zettabytes need big, big DCI

As digitization envelops everything from healthcare to commerce, entertainment and simple communication, the need for data storage and connection has ballooned.

It’s difficult for the mind to grasp just how much data is present in data centers and in-flight globally. IDC offers an interesting study that pegs the global datasphere at 33 zettabytes in 2018, growing to 175 zettabytes by 2025.

But how big is a zettabyte?

1021 bytes

 You might say that’s a big! number, but what’s it mean?

Data scientists offer practical calculations to help us comprehend the scale of data flying around networks. My favorite was made by University of Pennsylvania professor, Mark Liberman, who estimates that all speech ever spoken by the human species would need 42 zettabytes of data (if digitized as 16kHz, 16-bit audio). That means the datasphere in mid-2019 is now equal to every word ever spoken by all humans throughout history.

Data is useless if it can’t be accessed. Any application we can think of requires connection to the data centers where this huge datasphere lives. IDC also predicts that by 2025, roughly half of the datasphere will be stored in public cloud data centers, implying that many petabytes of data will be in-flight at any moment. Data center interconnect (DCI) needs to keep pace.

Optical networks are the backbone of DCI. Datasphere growth has driven increases in DCI optical line capacity: from 10, 40 and 100Gbps now to 400 and 600Gbps and beyond. These requirements tax the fundamental information capacity of optical fiber as defined by the Shannon limit.

Nokia is busy helping network operators ensure they can meet the demand. In 2017, Facebook completed submarine field trials over a 5,500km undersea cable between New York and Ireland. The trials proved the feasibility of probabilistic constellation shaping (PCS), a modulation shaping technique that dynamically adjusts transmission capacity of a particular optical span to approach the Shannon limit.

As part of Nokia’s Photonic Service Engine 3 (PSE-3) silicon, PCS helps operators economically construct higher capacity DCI across any span length. Recently, Nokia conducted PSE-3 trials with several operators including M-net in Germany, Netia in Poland and TIM in Italy. Each of these trials raised the bar in distance spanned and capacity transmitted. M-net proved the ability to transmit 500Gbps per wavelength over a regional network, with specific spans rate-optimized by PCS. Netia showed how PCS could more than double capacity in a live, production network. TIM achieved a European capacity speed record, exceeding 550Gbps per wavelength across a 350Km span and 300Gbps over a 1,750Km span.

With PSE-3 implemented in the Nokia 1830 PSI-M solution for hyperscale DCI, network operators of all types will be able to build DCI networks that connect the largest of routers and data centers. Visit us at NANOG 76 in Washington, DC, on June 11 and see for yourself! 

Share your thoughts on this topic by joining the Twitter discussion with @nokianetworks or @nokia using #optical # opticalnetworking

About Chris Janson

Chris Janson is Senior Product Marketing Manager for optical networks, where he follows trends in optical networking technology and its application to finance, healthcare, utilities, government and educational network operators. Chris has held engineering and marketing roles in the communications equipment and semiconductor fields and has shared his work through many webinars, articles and videos. He also serves on the board of directors of the Rural Telecommunications Congress and the non-profit OpenCape Corporation. Chris holds an MBA from Boston University and Bachelor of Science in engineering from Wentworth Institute of Technology.

Tweet me at @cj01950