Nokia breaks capacity records using Facebook submarine cable

Nokia has shocked the world once again, breaking the capacity record over Facebook’s 5500 km submarine cable between New York and Ireland.

Using Nokia Bell Labs’ probabilistic constellation shaping (PCS) technology, the pair achieved spectral efficiency of 7.46 b/s/Hz and increased the stated capacity of the system by almost 2.5 times. If that wasn’t enough, hold onto the edge of your seat, because the 11000 km round trip submarine transmission achieved a record spectral efficiency of 5.68 b/s/Hz, as well as a first demonstration of 200 Gbps and 250 Gbps wavelengths. Take that Huawei.

Although the team at the Guinness World Records might not be bouncing with excitement, it is a notable breakthrough for the pair. Facebook’s business is fast moving towards video to satisfy the increasing impatient consumer, but networks have to be capable of dealing with bandwidth-hungry applications such as video and virtual reality. Video is big business, but if you don’t have the technology to deal with the stress on the network, you’re not going to get very far.

“Facebook wants to increase the pace of innovation and adoption of next-generation optical technologies,” said Stephen Grubb, Global Optical Network Architect at Facebook

“This field trial with Nokia demonstrates that the scalable optical technology of PCS together with narrow linewidth laser sources can achieve capacities extremely close to the Shannon limit. This ensures that we are both maximizing our investment in submarine cable systems, as well as continuing to drive the cost per bit of submarine transport lower.”

PCS is a relatively new concept, using ‘shaped’ quadrature amplitude modulation (QAM) formats to flexibly adjust transmission capacity to near the physical limits of a given fibre-optic link. The pair claim the test is a first-of-a-kind, and demonstrates the potential to upgrade this cable to 32 Tb/s per fibre in the future.

As more and more video finds its way onto the Facebook platform, the commercial availability of such technology becomes more important. And if you think there a lot of video on there already, just wait.

During the company’s last earnings call in February, the team highlighted it was adding more features to make the uploading and viewing of video even easier. This also including improvements to the video calling features, as well as Facebook Live. The team claim now more than 400 million people now use voice and video chat on Messenger every month, as well as Instagram Stories reaching 150 million daily active users. That’s some serious video demand.

“We are thrilled to partner with Facebook to promote our common commitment to accelerating innovation in optical transmission,” said Sam Bucci, Head of Optical Networking at Nokia.

“By demonstrating promising areas of Nokia Bell Labs research such as PCS, as well as coherent technologies available today, we hope to chart a path forward for the industry towards higher capacities, greater reach, and more network flexibility.”