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.
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.