Which thing need consider when deploy 400G between data center distance in 120KM?

 In an era characterized by explosive data growth and the relentless expansion of cloud computing services, the demand for high - speed and long - distance data transmission between data centers has reached unprecedented levels.

For 100M distance, can use the following solution. But for Longer distance, HTF also has the solution.

400G optical transmission technology represents a significant leap forward in data communication. It offers extremely high bandwidth, enabling the transfer of vast amounts of data in a short time. For data centers, which serve as the core hubs of data storage and processing, 400G can meet the increasing requirements for data exchange between different centers, such as real - time data synchronization, large - scale data migration, and cloud service interoperability. The higher data rate not only improves the efficiency of data center operations but also provides a solid foundation for emerging technologies like artificial intelligence and big data analytics, which rely on rapid data transfer.

However, when considering a 120 - kilometer distance between data centers, several challenges need to be addressed. One of the primary obstacles is optical signal attenuation. As light travels through optical fibers, its power gradually decreases due to factors such as absorption and scattering within the fiber material. Over a 120 - kilometer span, the attenuation can be substantial, potentially degrading the signal quality to a point where data errors occur frequently.

Another critical issue is chromatic dispersion. Different wavelengths of light in an optical signal travel at slightly different speeds in the fiber, causing the signal to spread out over time. In long - distance transmission, chromatic dispersion can lead to inter - symbol interference, which severely impacts the integrity of the transmitted data.

Despite these challenges, there are several technological solutions that can make 400G deployment over 120 kilometers a reality. Advanced optical amplifiers, such as erbium - doped fiber amplifiers (EDFAs) and Raman amplifiers, can be strategically placed along the fiber route to compensate for signal attenuation. EDFAs boost the optical signal power by amplifying the light within the fiber using the gain medium of erbium - doped fiber, while Raman amplifiers utilize the Raman scattering effect in the fiber to amplify the signal over a wide bandwidth.

To deal with chromatic dispersion, dispersion , HTF use coherent optical module to solve the this chromatic dispersion issue. Use coherent optical module, so don't need consider the DCM. Less optical parts.

In addition, modulation formats and coding techniques also play crucial roles. Advanced modulation formats like quadrature amplitude modulation (QAM) can increase the spectral efficiency of the 400G signal, allowing it to carry more data per unit bandwidth while maintaining a certain level of tolerance to signal degradation. Forward - error - correction (FEC) coding can detect and correct errors that occur during transmission, improving the reliability of the data link. By combining these technologies, it is possible to achieve stable 400G transmission over 120 kilometers.

HTF can hel pyou deploy 400G between data centers separated by 120 kilometers, Max support 40x400G, If need upgrade your data center network, welcome to contact HTF. ivy@htfuture.com

16T DWDM solution with OLP

 First open 1x400G, future max can expand to 40x400G=16000G.  Help you save fiber rent and cost. 

OLP offers high reliability with automatic failover, dual-path protection, 

transparency, easy deployment, cost-effectiveness, and wide applicability for optical networks.

Point-to-point transmission, Dual fiber

Single channel transmission: 400G

Primary line distance: 80km 

Secondary line distance : 100km

Span attenuation: 0.3dBm/km

DWDM Application scenarios of 400G technology

 400G wavelength division technology is a bearer technology for the next decade. The total bandwidth of the 80*400G system reaches 32T. Considering the current traffic growth, network construction cost, and technology evolution, priority is given to the construction of 400GE port supporting networks in the backbone 163 hotspot areas and some metropolitan IP services, as well as the large bandwidth bearer scenarios for government and enterprise customers of East Data West Computing, multi-AZ connections between clouds, and intelligent computing:

Backbone communication network: From the current analysis of the growth of backbone 163 traffic and flow direction, the traffic between the major economic circles of Beijing-Tianjin-Hebei, Yangtze River Delta, Guangdong, Hong Kong and Macao, and Chengdu-Chongqing is relatively large, and the long-distance 400G QPSK technology can meet the construction of regional ROADM networks. Other areas of the backbone network can continue to use the original 100G ROADM network for traffic carrying. For some provincial trunks, PCS-16QAM technology can be considered, with a capacity of up to 48T and a lower cost than QPSK long-distance technology.

Metro communication network: Around the East Data West Computing hub node, the bandwidth growth in the provincial trunk and metropolitan area is expected. According to the expected traffic growth, 400G networks can be built in some provincial trunk hub nodes, East Data West Computing nodes, and metropolitan core nodes to meet the demand for bandwidth growth.

Cloud-to-cloud large bandwidth network: For highly reliable multi-AZ cloud-to-cloud and cloud-to-intelligence interconnection scenarios, the current 100G network has a total bandwidth of 8T, which cannot meet its business needs. Considering the occupied computer room, power consumption, operation and maintenance, and single bit cost, it is better to introduce 400G or higher speed to solve the requirements of large-scale data processing and storage for high-speed interconnection.

Four future development trends

The popularity of ChatGPT has promoted the construction of domestic intelligent computing centers. With the implementation of intelligent computing centers, intelligent computing applications will be launched quickly, and AI-generated videos will become easier and easier, further generating new traffic and promoting network connections. With the expansion of the application scale of 400G, the maturity of the industrial chain will further promote technological innovation and reduce manufacturing costs. In addition, with the development of silicon photonics technology, the future 400G wavelength division system will be more efficient, energy-saving, and less expensive.

If you want to build 400G dwdm transmission network, welcome to contact Ivy from HTF. ivy@htfuture.com