Heralding the Beyond-100G Era
The next three to five years will be a period of rapid development of broadband networks in China. As a variety of new services gradually mature and are widely deployed, the demand for network bandwidth will grow exponentially. Due to the surging bandwidth growth, the existing 100G OTN capacity has become increasingly saturated. With the development of beyond-100G OTN technologies, it has become an inevitable trend to deploy the beyond-100G OTN.
Big Video Brings a Surge in Bandwidth Demand
China is now in the early development stage of big video services represented by 4K. The bandwidth demand at the MAN core layer will be greater than 6 Tbps. It is estimated that by 2019 to 2020, the bandwidth demand at the MAN core layer will be greater than 12 Tbps, so a single 100G OTN plane can no longer meet the requirement of big video development. It is therefore imminent to increase the speed of OTN.
5G Era Requires Extreme High-Speed Pipelines
Wireless services are one of major business sectors of operators. It is estimated that 5G commercial trial will begin in 2020. Compared with the 4G era, it is generally agreed in the industry that the bandwidth demand in the 5G era will increase 100 to 1000 fold. Considering the unified transport of wireline and wireless networks in the 5G era, the MAN convergence layer will require multiple 100 Gbps channels, and the MAN core layer will even require a bandwidth of more than 10 Tbps. It can be said that 5G development will bring another round of explosive bandwidth growth. It is a general trend to deploy beyond-100G OTN at both the MAN core and backbone layers.
IDC Interconnection Accelerates the Arrival of Beyond-100G Era
However, with the arrival of the cloud network era, data centers will become core carriers of future telecom networks. The rapid expansion of IDCs brings huge pressure to bandwidth for direct connection. Now the typical output rate of core IDCs is 100 GE, and it will be escalated to 400 GE in the future. The 100G OTN system in the existing network consumes enormous resources. Therefore, it is imperative to use beyond-100G OTN to build high-speed interconnection channels to meet the demands for high DCI bandwidth and low latency.
This is the reason why major operators worldwide are focusing on beyond-100G technologies. In 2017, China Mobile first introduced the 200G OTN model in its provincial-level concentrated purchase and actively promoted the commercial deployment. Compared with 100G OTN, 200G OTN can provide larger transmission bandwidth, support future development of big video and 5G services, and reduce the unit power consumption by 40% to 50%, thereby helping operators solve the conflict between bandwidth needs and power consumption. At present, 200G OTN has been commercially deployed in many Chinese provinces, and the transmission capacity has continually increased. With the maturity of the entire industry chain and key technologies, a new ultra-wide, green, and easy-to-use OTN era has arrived.
Leading Beyond-100G OTN Forward
ZTE has been committed to the design, research and development of WDM/OTN products. From 2.5G WDM to new-generation beyond-100G OTN, ZTE has been at the forefront of developing optical transport products. In terms of OTN core competitiveness, ZTE North America R&D Institute focuses on researching cutting-edge OTN technologies, with a number of core algorithms and technologies acknowledged as international patents. ZTE has made significant progress in improving transmission capacity, reducing power consumption and enhancing integration, and has secured a leading position in the industry. Its self-developed 16 nm chips and 100G/beyond-100G optical modules have been put into commercial use, helping operators address their practical deployment issues.
Compared with 100G OTN, ZTE’s beyond-100G OTN uses industry-leading key technologies to considerably improve system performance that can meet operator needs for long-term evolution.
Polarization-Multiplexed High-Order Phase Modulation Improves Spectrum Efficiency
ZTE's beyond-100G OTN uses various high-performance modulation techniques such as PM-16QAM and PM-8QAM and can double spectrum efficiency compared with 100G OTN. The transmission capacity of a single optical fiber increases from 8 Tbps to 20 Tbps or above. This significantly promote the rapid growth of broadband business.
Advanced FEC Algorithm and Pre-Compensation Increase Greatly Transmission Distance
The key to commercial beyond-100G OTN is to increase transmission distance. ZTE has developed the FEC algorithm that has the best error correction capability in the industry, and its transmission capability is 1 dB larger than the industry level. ZTE North America R&D Institute has also proposed several pre-compensation technologies such as narrowband filter compensation and non-linear compensation, which can greatly improve transmission capability of beyond-100G OTN. When combined with hybrid amplifiers and new optical fibers, beyond-100G OTN can double transmission distance. This basically meets transmission needs in metrapolitan area or provincial backbone networks.
Silicon-Photonics Integration and ZTE-Developed AISC Chip Usher in a Green Beyond-100G OTN Era
Energy saving is a major concern of operators for reducing Opex. To achieve highly-integrated optical modules, ZTE uses the industry-leading silicon-photonics integration technology to integrate DSP, ADC/DAC, laser and driver on the same silicon base. This greatly reduces the size and power consumption of beyond-100G optical modules. ZTE has rolled out its newest beyond-100G OTN that uses the industry-leading 16 nm chip technology to considerbly improve the functions of a single chip and save power by 50%. Moreover, ZTE has completed commercial deployment of 200G/400G OTN and laboratory verification of 800G/1T transport rates, and has repeatedly refreshed the transmission records of beyond-100G OTN.
ZTE's Global Practice of Beyond-100G
ZTE's beyond-100G OTN has been extensively deployed around the globe and received wide recognition from users at home and abroad. According to the latest OVUM report, ZTE has established a solid No. 2 position in the market share of both global optical and OTN switched networks (Fig. 1).
ZTE has been involved in almost all commercial beyond-100G OTN projects of China Mobile. With large-scale applications in Zhejiang, Hunan, Anhui, and Henan provinces of China, ZTE has built extreme high-speed optical networks for China Mobile to support big video, 5G and IDC interconnection.
In 2016, ZTE worked with TMA to successfully deploy 400G OTN in Austria’s existing network. They increased the capacity of a single optical fiber to over 20 Tbps and achieved a transmission distance of 475 km over the hybrid 10G/100G/400G network, setting again a new world record. In 2017, ZTE cooperated with Ture, Thailand’s largest full-service operator, to build the world’s first commercial WDM automatic switched optical network (WASON) based on 200G/400G flexible grids. ZTE won more than 75% of the bid for building new backbone networks. The diamond- and bronze-level WASON guarantees high system availability while increasing capacity.
ZTE always adheres to its business philosophy of serving with dedication and being committed to customers. The company looks forward to cooperating with global operators in building extreme high-speed ultra-wide beyond-100G OTN.
Beyond-100G OTN Transport, extreme high-speed pipelines, polarization-multiplexed high-order phase modulation, advanced FEC algorithm, pre-compensation, silicon-photonics integration, ZTE-developed AISC chip