NTT Com to deploy 400G optical transmission system

07 April 2017 | Jason McGee-Abe

NTT Communications has today announced that they will begin deploying an ultra-large-capacity, space-saving and energy-saving 400Gbps optical transmission system in data centres for network connection.

NTT Com has taken practical steps to upgrade to 400G transmission technology – with deployment being implemented sequentially from 14 April - due to ever-increasing network demands for higher speeds and more data, including for 4K/8K and other high-resolution video data, the full-fledged expansion of IoT and big-data processing.

The system will raise the transmission capacity of NTT Com’s core network above 19Tbps per optical fibre, or more than double existing capacity. The system utilises the advanced digital-signal processing technology which is the result from Nippon Telegraph and Telephone Corporation (NTT)’s R&D.

NTT 07.04.17 - Figure 1

The main features and advantages of the 400G system are as follows:

- Top-level energy and space savings: The new system reduces energy consumption per bps by 75% and space requirements by 80% compared to the existing system. The savings were achieved through a synergistic combination of advanced digital-signal processing technology and 16nm complementary metal-oxide semiconductor (CMOS) technology. Energy-saving integrated circuits can be constructed rapidly, enabling transmitters to be quickly deployed even in confined spaces at data centres.

NTT 07.04.17 - Figure 2

- More than double existing transmission capacity: The new system achieves more than double the transmission capacity per optical fibre compared to its predecessor system. To generate 400G signals, the system utilises NTT’s research result :16 quadrature amplitude modulation (QAM) for both phase and amplitude, and sub-carrier multiple transmission.

- New OTN and 400GbE interfaces: In connection with the deployment, NTT Com will offer new optional network services for enterprises, including the sequential launch of OTN interfaces (OTU2, OTU2e and OTU4) mainly for wholesalers and data centre users, and a 400GbE interface incorporating framing technology compatible with OTUCn which is the result from NTT's R&D.

- Disaggregation architecture: To deliver new services and functions with even greater speed and flexibility, NTT Com will combine SDN technologies and dis-aggregation architecture, which can be redeployed as required according to function or module, replacing existing high-function, all-in-one dedicated equipment.

Going forward, NTT Com and NTT will jointly investigate further possibilities, including the deployment of PoC to deliver high-speed Ethernet signals, including 400GbE. Mindful of IEEE standardisation trends, they will pursue increased flexibility and agility for transmission networks by leveraging disaggregated equipment and SDN technologies.