Google’s new subsea cable delivers data speeds of 250TB per second

Subsea cable employs innovative space division multiplexing technology and high fibre count architecture 

A new subsea cable connecting the US and Europe and capable of sending the entire digitised library of commerce three times every second is online, Google has announced.

Named after Nobel Peace Prize winner and founder of the Red Cross, Henry Dunant, the now-operational cable will deliver record-breaking capacity between the US and French Atlantic coast.

Google said the cable, announced in 2018 and developed in partnership with telecommunications equipment company SubCom, will be instrumental in ensuring network infrastructure can keep up with spiralling cloud demand.

Distinguishing this cable from others is its use of space division multiplexing or SDM technology. SDM allows pump lasers and other optical components to be shared between several fibre pairs. Pump lasers typically amplify individual fibre pairs as data travels along them.

“Dunant is the first long-haul subsea cable to feature a 12 fibre pair space-division multiplexing (SDM) design, and will deliver record-breaking capacity of 250 terabits per second (Tbps) across the ocean – enough to transmit the entire digitized Library of Congress three times every second,” Chris Ciauri, president for the EMEA region at Google Cloud, explained.

“Increased cable capacity is delivered in a cost-effective manner with additional fibre pairs (twelve, rather than six or eight in past generations of subsea cables) and power-optimized repeater designs.”

Dunant is not the only subsea cable Google is investing in to support its growing cloud business. In July the company announced development on Grace Hopper, a cable connecting the US, the UK and Spain, and the first connecting the US. and UK since 2003.

Indeed, Google has been busy investing in all manner of infrastructure to support its cloud division, establishing more than 100 points of presence, thousands of edge node locations, 91 dedicated interconnect locations and 24 Google Cloud Platform (GCP) regions, with additional regions announced in places like Chile, Spain, Italy, France and Poland.

The impact of this expenditure on Google Cloud Platform’s bottom line was evidenced in Google’s full-year earnings report, published this week. Despite a record-breaking year in terms of cloud revenue, Google’s cloud unit posted annual losses of $5.6bn.