Cisco, Microsoft tap Acacia for 800Gbps subsea services

Created February 26, 2024
News and Business

Cisco and Microsoft have successfully transmitted 800Gbps on the Amitié transatlantic communications cable, which runs 6,234 kilometres from Boston, Massachusetts to Bordeaux, France. The trial was performed with the Cisco NCS 1014 platform enabled by Acacia’s Coherent Interconnect Module 8 (CIM 8), which is powered by its Jannu digital signal processor and advanced silicon photonics.

Cisco says this real-time field trial exceeded any industry trial performance to date with Dense Wavelength Division Multiplexing (DWDM) 800G in a 150GHz channel spacing, equivalent to a spectrum efficiency of 5.33bps/Hz and a maximum spectral efficiency of 5.6bps/Hz. In addition, 600G was transmitted over 12,469 kilometres for a trans-Atlantic loopback configuration. This is the first time a 140Gbaud single carrier signal was demonstrated live, and is the longest distance ever reported at single carrier 600G DWDM transmission on an SDM cable.

Amitié submarine cable features Space Division Multiplexing (SDM) technology with 16 fibre pairs, more than traditional subsea cables, with repeater power shared across the fibre pairs to deliver the highest cable capacity.

Cisco adds that the need for greater subsea network capacity, which requires advanced coherent transmission systems that support higher performance is largely being driven by the continued growth of cloud and explosion of AI services.

“In the era of AI, reliable and fast network connections are more important than ever,” said Bill Gartner, SVP Optical Systems and Optics, Cisco. “Working with Microsoft on the Amitié cable to demonstrate the potential for improved overall network capacity with 800G at these distances is a significant milestone for an SDM cable, and we’re proud to drive the innovations that pave the way for ever increasing network capacity needs.”

“The transmission of 800G over 6,234 kilometres is a milestone that demonstrates SDM cables can deliver increased capacity over traditional subsea cables,” said Jamie Gaudette, GM of Cloud Network Engineering, Microsoft. “This field trial demonstrates what is now a commercial technology for subsea routes, and we can improve the network capacity to help drive digital transformation for people, organizations, and industries around the world.”

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This article was written
by Peter Dykes

Peter Dykes is a independent telecoms and technology journalist who has over that last 30 years written for a wide range of B2B publications and companies. A former BT engineer, he specialises in networks and associated support systems. He is currently Editor of Optical Connections.