Advances in Nokia's coherent pluggable optics could reshape how subsea cable operators manage their infrastructure, according to remarks from the telecom equipment maker's Optical Networks Product & Solutions Marketing lead, Serge Melle. The technology, which has already become standard in terrestrial networks, is now moving into submarine cable deployments.
Coherent pluggable optics are compact modules that enable high-volume data transmission across fibre infrastructure while consuming less electricity and occupying less physical space than conventional systems. Performance has climbed steadily as digital signal processors have improved, pushing speeds from 100G and 200G up to 800G.
Melle explained the appeal: "Pluggable coherent optics, whether deployed in routers or in thin transponders, provide undeniable benefits for network operators in terms of lower power, greater system density and reduced cost per bit. Proven deployment in metro and long-haul networks thus has subsea cable operators asking whether these benefits can also be leveraged in subsea applications?"
Nokia tested its ICE-X 800G technology in partnership with Telxius on the Brazil-USA (BRUSA) submarine cable. The trial achieved 600G per wavelength over a 2,841km span, while also demonstrating a transmission record of 400G per wavelength across 5,862km.
The company sees practical applications for the technology across different use cases. "In many cases subsea cable operators can now also consider coherent pluggables to optimise for power, space or cost," Melle noted.
Yet Nokia acknowledged limits to the approach. Longer and more challenging routes—particularly cables exceeding 15,000km—will continue to require more robust traditional optical systems. The company expects future iterations of coherent pluggables to reach 800G speeds or beyond on transoceanic paths.
Melle summed up the trajectory: "As coherent pluggables continue evolving from terrestrial to subsea networks, they give operators a practical new option for balancing reach and capacity with lower power, greater density, simpler operations and improved cost per bit- while performance-optimised embedded optics remain essential for the most demanding routes."
