Cisco reaches 26.4 Tbps in the Marea transatlantic submarine cable between the United States and Spain

The tests, which have been carried out taking advantage of the flexibility of the NCS 1004 system, demonstrate the highest capacity and spectral efficiency achieved to date.

Cisco has successfully tested the operation of its platform Network Convergence System (NCS) 1004 on the sea, the 6,600-kilometer submarine cable system that connects the United States with Southern Europe, from Virginia Beach (Virginia) to Bilbao (Sopelana beach, Spain).

The test consisted of providing greater transatlantic bandwidth, among other capabilities. Taking advantage of the flexibility of the NCS 1004 system, various combinations of channel capacity were tested to maximize the performance and spectral efficiency of the cable, obtaining record results: a 400G error-free performance in the Virginia-Bilbao test and channels with a 6.445 bps/Hz spectral efficiency (bits per second/hertz); and a spectral efficiency of 4.52 bps/Hz in the case of the return loop (from Bilbao to Virginia and back to Bilbao) for a distance greater than 13,200 km.

Network operators do not have unlimited bandwidth, so spectral efficiency is the most important measure in subsea deployments. This measurement refers to the speed that can be transmitted over a given bandwidth, checking the effectiveness of the physical layer when using a limited frequency spectrum. The spectral efficiency of a communication link can be improved by packing more information or bits into a single transmission.

The Cisco NCS 1004 platform has thus achieved a maximum capacity of 26.4 Tbps on the Marea cable, reaching up to 18.9 Tbps for transatlantic loopback.

Bill Gartner, Senior Vice President and General Director of Optical Systems and Optics at Cisco, highlights that “this shows that 24.7 Tbps can be comfortably used over MAREA, being able to deploy up to 18.5 Tbps for double the distance in the case of the return loop, also with a wide margin.”

The Cisco NCS 1004 platform has been designed to maximize fiber wavelength and capacity in a compact size and with lower energy consumption. In 2RU, the system supports up to 4.8 Tbps of client and 4.8 Tbps of trunk traffic. Cisco NCS 1004 delivers DWDM transport capabilities with agility, programmability, and ease of use. The Cisco NCS 2000 system working with the NCS 1004 offers agility, programmability and massive scalability for ultra-long distance, submarine, metropolitan and enterprise optical networks.