In the 5g era, the coordination and common development of fixed and mobile networks are the inevita ble trend of network development. Transmission networks, data centers and access networks are fac ing new challenges brought by business development. Therefore, it is necessary to accelerate the u pgrading and coverage of all-optical networks to deal with the impact and change of emerging servi ces on the whole network in the 5g era. With the official commercialization of 5g, new services su ch as VR / AR video, cloud games, robots and Internet of vehicles are emerging. These services not only need the existing transmission network to support high bandwidth, low delay and high reliable performance, but also need to meet the requirements of massive device connection, ultra-high traffic and high-speed mobility.

In the 5g era, various businesses and applications are gradually evolving to the cloud, and the fun ctions of forwarding, control and management will also accelerate the cloud deployment. Therefore, the data center has become the center of Internet content and traffic. According to statistics, the compound annual growth rate of the rack in the data center machine room is 32%, and the flow betwee n DCs increases rapidly, with an annual growth rate of more than 50%. Data has shown massive, dive rsified and unstructured development, and the infrastructure has gradually evolved to cloud edge en d. It is an inevitable trend for the development of network to coordinate and develop together.

It is understood that in the current development of access network, the proportion of optical fiber t o home users of the three major domestic operators has reached 92%, and the proportion of broadband u sers above 100m has been close to 82%. There are 31 provinces carrying out 500m commercial, 25 province s carrying out 1000m commercial, 17.9 million users above 500m and 910000 Gigabit users. The access n etwork is gradually entering the era of Gigabit commercial. Therefore, transmission network, data cente r and access network are facing new challenges brought by business development.

In terms of transmission network, by 2025, the world will have 6.5 million base stations and nearly 2.8 billion 5g users. As the upper foundation of the whole network, the transmission network needs t o be upgraded and optimized first.

In terms of data centers, at present, there are more than 500 super large data centers in the world, and about 150 are planned or under construction. Moreover, the data centers are facing three major tr ends: the evolution from 100g to 400g, the transformation from photoelectric mixing to all-optical, an d the transformation from centralized computing to "core Gan point + edge technology".

In terms of access network, it is expected that the global broadband users will reach 1.27 billion in 2024. 234 operators in 57 countries have announced the Gigabit broadband construction plan, and 10 Gigabit home access has been put on the research agenda. The network is evolving from 1gpon to 10gpon and 50gpon.