Colt Technology Services announced that it has succeeded in transmitting 600 Gbps wavelength division multiplexing over a commercial long-distance network for the first time in Japan. The company succeeded in a wavelength division multiplexing transmission experiment of 400 Gbps in December 2020, and this time it is said to follow this. We connected large-scale data centers in Japan (location is not open to the public) and transmitted using Ciena’s WaveLogic 5 Extreme system. He also used Viavi Solutions’ ONA-1000A, MTS-6000A, and OSA-610 to test a combination of end-to-end bit error-free traffic for 400Gbps and 100Gbps Ethernet clients and line-side optical spectrum health analysis. From the latter half of 2021, the company plans to provide commercial services at 400 Gbps for businesses that transmit large volumes of data such as wholesale, media, global content networks, and Over the Top. Although there are no plans for commercial services using 600 Gbps this time, the company plans to continue to provide stable broadband services and jointly promote efforts to realize further wideband communications such as 800 Gbps.