The test was to demonstrate the ability to provide increased transatlantic bandwidth as well as simulate transpacific distances via loopback on one end of the cable. Leveraging the flexibility of the NCS 1004, several channel capacity combinations were tested to maximize the performance and spectral efficiency on the cable. Network operators do not have unlimited bandwidth so spectral efficiency is the most important measurement in subsea deployments.

source https://finance.yahoo.com/news/cisco-demonstrates-26-4tbps-marea-070000591.html?.tsrc=rss