ZTE Assists China Mobile in Building the World’s Largest 100G/200G OTN Network

Release Date:2022-11-16 By Li Xianfeng

As we are moving towards the intelligent era and generating a massive amount of data, the global optical network industry has fully entered the beyond-100G era. China Mobile is also continuously increasing its strategic investment in this field to secure its leadership position in the global market. In its phase 13 centralized procurement of the inter-provincial backbone transport network equipment, China Mobile worked with ZTE to construct the world's largest 100G/200G OTN covering 19 provinces, laying an ultra-broadband and ultra-fast transport base for the explosive growth of big data and the east-data-west-computing project.

 

With the large-scale deployments of 5G networks, home broadband and enterprise services have experienced fast growth. As a result, the inter-provincial traffic grows at a compound annual growth rate (CAGR) of over 40%, posing continuous challenges to the bandwidth efficiency of backbone transport networks. Meanwhile, as the network scale, the number of site degrees and the number of services are rapidly increasing, the traditional WDM network has been unable to satisfy the requirements on service scheduling and network O&M. Therefore, the optical networks also have to deal with the challenges of flexible scheduling and intelligent O&M.

 

To address these technical challenges brought by network development, China Mobile adopted multiple key technologies including single-wavelength 200G, ultra-wide extended C band, optical cross-connect (OXC), SDN and high-density boards to enhance network performance in a comprehensive way, which has ushered in large-scale deployment of 200G optical transport, OXC, and SDN in China.

 

In terms of network capacity, the single-wavelength 200G achieves the best balance between capacity and distance with the application of multiple high-order modulation techniques. The western network employs 200G QPSK and 200G 16QAM modulation schemes according to link quality so that the enormous and complex provincial and municipal nodes distributed across the central and western regions can be connected to be the largest optical network. The 200G QPSK almost matches the 100G QPSK in transmission distance, but increases the capacity by 50%. The 200G 16QAM doubles the capacity with the spectral bandwidth of 4 THz remaining unchanged.

 

In terms of flexible scheduling, OXC makes it possible to schedule any service on the optical layer. ZTE’s 32-degree OXC device can schedule wavelengths flexibly in 32 directions, and wavelength assignment can be performed with one click using the network management system, with no site visits required. One board can integrate the functions of up to eight boards, and high integration allows the equipment room footprint to be saved by up to 75%. All fibers between boards are interconnected via flexible optical backplanes, which reduce the complexity and errors of manual fiber connections as well as the difficulty of subsequent maintenance.

 

With respect to intelligent O&M, SDN enables end-to-end one-click service configuration and management to decrease a large amount of O&M manpower and material resources. The permission- and domain-based management models guarantee network security. Visualization of resource statistics and early warning provide a clear resource analysis for network maintenance, ensuring proper network capacity redundancy and sufficient bandwidth for burst service transport.

 

In line with the national low-carbon strategy, China Mobile takes high integration and low power consumption as major indexes of equipment assessment. Powered by the highly integrated Framer chip developed by ZTE, ZTE’s OTN equipment cuts the power consumption by 50%, reaches 1T single-slot bandwidth and realizes 10×100G or 5×200G ultra-broadband transport in a single board.

 

Together with ZTE, China Mobile has applied multiple new technologies to the world's largest 100G/200G OTN to handle the soaring traffic volumes. The high-quality development of China's economy is associated with the construction of national infrastructure such as high-speed optical networks. The integration of optical networks with various industries and fields will facilitate full use of resources and efficient operation of the society, thus effectively boosting economic prosperity and growth. It is necessary for the Chinese ICT industry to move from building an “information superhighway” to cultivating an “information industry ecosystem”, which is also an indispensable way to accelerate the development of the global ICT industry.