With the rapid development of 4K, 8K, big video, 5G, Internet/mobile Internet, Internet of things, IDC and so on, the new demand strongly promotes the accelerated innovation of optical transmission technology. "Ultra-high speed, ultra-large capacity, ultra-long distance, ultra-low loss, ultra-low cost" is the rigid demand of optical network. Optoelectronic integration, SDN/NFV and cloud-based are the three elements of optical network evolution . Ultra-high speed, IP, optoelectronic integration and silicon-based, intelligent and open is the development trend of optical network .

At present, the standardization of over 100G is progressing smoothly, and the optical modules of corresponding rate interfaces are gradually maturing. Over 100G has been gradually put into pilot and small-scale applications in 2018.

In the case of over 100G, there are still a variety of coexisting and competing codes for commercial products of 200G and 400G high-speed transmission, and there is a trade-off between transmission distance and spectrum efficiency.  At present, high-order modulation formats represented byPM-64QAM and PM-256QAM have also begun to compete in short-range application research. The single-carrier 400G research heats up, OIF established a 400ZR working group in November 2016 and started the research. At the same time, the equipment manufacturers and operators jointly conducted the test of 400G, and a small number of commercial trial systems have been developed. The single carrier 400G has become one of the application options for the transmission of the next generation backbone network.

From the perspective of the whole 5G carrying capacity, the transmission carrying capacity network is divided into two layers, the core convergence layer and the access layer. Since the two layers of the metropolitan area bearer network are not completely corresponding to the pretransmission, medium transmission and return transmission of 5G network, the technical means of the two layers of the metropolitan area bearer network do not require the end-to-end uniformity, but hope to realize the end-to-end arrangement of network services with SDN technology. The construction of the metropolitan area bearer network is gradually evolving according to the needs of 5G services, without requiring one step in place.

The gradual commercial deployment of 5G and the increasing popularity of mobile terminal equipment also pose major challenges to access networks.

The growth rate of mobile traffic is 20% ~ 25% higher than that of the overall Internet traffic. After the deployment of LTE networks, from 2015 to 2018, due to the popularity of video calls, massively multiplayer online games and widely used mobile payments, travel and other Internet applications, China has experienced tremendous traffic growth. China mobile and other operators have revised their 5G pre-transmission network architecture, leading to a surge in demand for the optical modules used in wireless pre-transmission.

Relevant projections show that the 5G era will be a large-scale commercial 25G wireless optical module. It is estimated that 50 million 25G/50G optical modules will be needed only in the 5G pre-transmission field, and the middle transmission field is also a new growth point. In the future, the 5G access layer and the aggregation layer need to introduce a 25G/50G rate interface, while the core layer needs to introduce an interface with a rate of 100G or higher.

In the face of the further development of the data center in the 5G era, ETU-Link is also expanding data center market to provide data center optical module solutions for operators and Internet vendors, such as 25G optical modules , 100G optical modules, AOC active optical cables, DAC high-speed cables, etc., according to the needs of different users to provide customized products.